HX64088243 QP905 .J13 Experimental pharmac Columbia Winibtx&ity> \ inttieCitp of i^citi l^orfe CoUese of l^^v^itimi anb ^urseon£( 3^ef erence i^ibrarp Digitized by tine Internet Arciiive in 2010 witii funding from Open Knowledge Commons (for the Medical Heritage Library project) http://www.archive.org/details/experimentalphaOOjack EXPERIMENTAL PHARMACOLOGY BY DENNIS E. JACKSON, Ph.D., M.D. ASSOCIATE PROFESSOR OF PHARMACOLOGY, WASIllKGTON UNIVERSITY MEDICAL SCHOOL, ST. LOUIS. WITH THREE HUNDRED NINETY ORIGINAL ILLUSTRA- TIONS INCLUDING TWENTY-FOUR FULL-PAGE COLOR PLATES ST. LOUIS C. V. MOSBY COMPANY 1917 Yyj^A. Copyright, 1917, By C. V. Mosby Company Press of C. V. Mosby Company St. Louis PREFACE. For several years the writer has liad a growing convic- tion that the teaching of pharmacology might l^e greatly facilitated, and rendered much more effective and compre- hensive, if each student could have in his own hands a laboratory manual giving exact, specific, detailed directions for carrying out most of the experiments which he will be called upon to perform in the study of this most inter- esting, vital and complex subject. The small number of manuals of this character w^hich heretofore have appeared in this field may be most strikingly compared with the very large number of laboratory manuals which have been pub- lished on such subjects as chemistry, botany, physics, zoolog}^, etc. And the thoughtful teacher might be at once inclined to ask himself whether or not the general scope and character of the work .done in these various experi- mental fields may not have been to some extent indicated by the number and character of experimental manuals de- voted to these subjects. In consideration of these points the author has therefore ventured to hope that in present- ing this manual of experimental pharmacology^ to teachers and students, some small amount of good may be accom- plished. My especial thanks are due to the publishers, Avho have rendered every assistance they could in the progress of this work; to Mr. Paul Knabe, who has faithfully devoted much time and labor to the proof reading, the arrangement of the illustrations, and the printing of the book; and to Mr. Paul P. Halleck, who in making the drawings contained herein has given me the advantage both of his extensive experience as an artist, and of his special training as a physician. I am deeply indebted to Mr. John A. Higgins, 4 PKEFACE who for seven years has faithfully assisted me in per- forming most of the experiments from which the tracings illustrated in this book have been mainly derived. D. E. J. Pharmacological Laboratory, Washington University Medical School. CONTENTS. PART I. PRELIMINARY EXERCISE. PAGE Assignment of Tables and Permanent Apparatus ...... 33 EXPERIMENTS. I. Ether. (Action on the Central Nervous System. — Cerebrum.) . . 53 Chloroform. (Action on the Central Nervous System. — Optic Lobes.) 55 Ether, Ethyl Chloride, Chloroform, Ethyl Bromide. (Irritability and Conductivity of Nerve.) 57 Ethyl Chloride. (Local Anesthesia.) 64 II. Ether. (Action on the Heart. — Dissection for the Vagus Nerve in the Frog.) 65 Chloroform. (Action on the Frog's Heart.) 70 Chloroform. (Action on Lymph Hearts.) 70 III. Turtle: Vagus Dissection. (Action of Ether on the Heart.) . . 71 Chloroform. (Action on the Turtle's Heart.) 76 IV. Ether, Chloroform, Ethyl Bromide. (Dog: Respiration, Blood- pressure, Cervical Vagi, and Sympathetics.) 77 Anesthetization of the Animal 77 Insertion of Tracheal and Carotid Cannulas; Isolation of Vagi and External Jugular Vein 85 Insertion of Femoral Injecting Cannula ; Dissection of Femoral Artery and Vein and Saphenous Nerve 93 Recording Blood-pressure 96 Recording Respiration 97 Adjustment of Writing Points 98 Other Methods of Recording Respiration 98 Beginning of the Records 99 V. Ether, Chloroform, Ethyl Bromide. (Dog: Motor Areas, Blood- pressure, Blood, Heart.) 103 Dissection of Pulmonary Artery and Vein 112 VI. Nitrous Oxide, Carbon Dioxide, Oxygen. (Frog: Central Nervous System.) .113 VII. Nitrous Oxide, Ethyl Chloride, Carbon Dioxide, Increased Atmos- pheric Pressure, (Decreased Atmospheric Pressure.) (Frog, Guinea Pig, Rat, Kitten, or Pup.) 117 Paul Bert's Experiment 120 6 CONTEjSTTS PAGE VIII. The Closed Method of Anesthesia. For Ether, Chloroform, Ethyl Chloride, Ethyl Bromide, (Nitrous Oxide), ''Somno- form, " etc., with Oxygen, Student Method. (Dogs or Cats.) 121 IX. Intratracheal Insufflation 129 X. Alcohol. (Frog: Central Nervous System, Heart and Vago- sympathetic Nerve.) 13.3 XI. Alcohol. (Turtle: Heart and Vagus Nerve.) 135 XII. Ethy] Alcohol, Brandy, Whiskey, Wine, Methyl Alcohol, Amyl Alcohol. (Dog: Blood-pressure, Eespiration, Esophagus.) 136 XIII. Whiskey or Brandy. (Reaction Time.) . 144 XIV. Alcohol, Whiskey, Brandy, Wine. (Dog or Cat: Myocardio- graijLic Tracings, Cardiac Sympathetic Nerves.) .... 147 XV. Antiseptic Action of Alcohol 157 XVI. Alcohol, Brandy, Urethane, Chloral. (Dog: Blood-pressure, Resj^iration, Cerebrospinal Fluid, Kidney or Sjjleen.) . . 158 XVII. Chloral Hydrate, Urethane, Paraldehyde, Chloretone. (Frogs: Central Nervous System.) 168 XVIII. Chloral Hydrate. (Action on the Frog's Heart.) .... 169 XIX. Chloral Hydrate. (Frog: Retinal Circulation With the Ophthalmoscope.) 169 XX. Chloral Hydrate, Adrenaline. (Turtle's Heart.) ...... 172 XXI. Chloral Hydrate and Alkalis 172 XXII. Morphine. (Frog: Central Nervous System.) 172 XXIII. Thebaine, Codeine. (Frog: Central Nervoiis System.) . . . 173 XXIV. Morphine. (Chemical Test for Morphine.) 173 XXV. Morphine. (Dog: Respiration, Excretion, Pupils, Central Ner- vous System, General Symptoms.) 175 XXVI. Fehling's Test for Reducing Bodies 176 XXVII. Morphine. (Cat: General Symptoms, Central Nervous System.) 177 XXVIII. Morphine, Codeine. (Dog: Respiration, Blood-pressure, Oxy- gen Consumption, Urine.) 177 XXIX. Morphine, Codeine, Pantopon, Heroine, Peronine, Dionine, Nar- cotine or Thebaine. (Spinal Dog: Bronchioles.) . . . 194 XXX. Heroine or Codeine. (Spinal Dog: Blood-pressure, Lung Vol- ume and Bladder Contractions.) 206 XXXI. Strychnine. (Frog: Action on the Cord.) 217 XXXII. Strychnine. (Frog: Heart and Vago-sympathetic Nerve.) . 220 XXXIII. Strychnine. (Turtle: Heart and Vagus Nerve.) 220 XXXIV. strychnine. (Dog: Blood-pressure, Respiration, and Kidney, Spleeii or Intestinal Loop.) 222 XXXV. Strychnine. (Ether, Morphine, Chloral Hydrate.) (Dog: Blood-pressure, Respiration, Oxygen Consumption, Air Em- bolism.) 226 CONTENTS PAGE XXXVI. Strychnine. (Student: Reaction Time.) 2.30 XXXVII. Picrotoxine. (Frog: Action on Medulla and Cord.) . . . 2.31 XXXVIII. Picrotoxine, Chloretone. (Dog: Blood-pressure, Respiration and Kidney, Spleen or Intestinal Loop Volume.) . . 23.3 XXXIX. Hydrastine. (Frog: Spinal Cord.) 238 XL. Hydrastine. (Frog: Heart and Vagus Nerve.) 240 XLI. Hydrastine. (Turtle: Heart and Vagus Nerve.) .... 241 XLII. Caffeine. (Frog: Central Nervous System, Muscles.) . . 241 XLIII. Caffeine. (Frog: Muscle and Nerve.) 243 XLI V. Caffeine. (Frog: Heart and Vagus Nerve.) 244 XLV. Caffeine. (Turtle: Heart and Vagus Nerve.) 244 XL VI. Caffeine. (Man: Reaction Time.) 244 XLVII. Caffeine. (Frog: Muscular Work.) 245 XLVIII. Caffeine. (Rabbit: Diuresis, Cervical Nerves, Depressor.) . 247 XLIX. Caffeine, Sodium Sulphate. (Dog: Blood-pressure, Diuresis, Respiration, Sciatic Nerve.) 249 L. Diuretine, (Sodium-theobromine-salicylate), Agurine, (So- dium-theobromine-acetate). (Rabbit: Diuresis and Res- piration.) 253 LI. Urea, S. A. Matthews' Solution, or Saline Diuretics. (Rab- bit or Cat: Diuresis.) 254 LII. Curara. (Frog: General Action, Claud Bernard's Experi- ment.) 255 LIII. Curara. (Frog: Heart and Vago-sympathetic Nerve.) . . 257 LFV. Curara. (Turtle: Heart and Vagus Nerve.) 257 LV. Curara, Strychnine. (Dog or Cat: Blood-pressure, Respira- tion, Urine, Sciatic Nerve. Dog: Salivary Ducts and Nerves.) 257 Dog 250 LVI. Coniine. (Frog: Heart and Vagus Nerve.) 260 LVII. Coniine. (Turtle: Heart and Vagus Nerve, Lungs and Sym- pathetic Nerves.) 260 LVIII. Coniine. (Dog: Blood-pressure, Respiration, Salivary Glands and Kidney, Spleen or' Intestinal Loop.) 265 LIX. Atropine. (Frog: Heart and Vagus Nerve.) 268 LX. Atropine. (Frog: Muscle and Nerve) 269 LXI. Atropine. (Turtle: Heart and Vagus Nerve.) 269 LXII. Atropine. (Cat, Guinea Pig, Rat, Dog, Pigeon, or Chicken: Pupil.) 269 LXIII. Atropine. (Dog, Cat or Rabbit : Blood-pressure, Respiration, Heart and Vagus Nerve, — Dog, Salivary Secretion and Chorda Tympani, Sweat Nerves, Pancreatic Secretion.) 270 LXIV. Scopolamine. (Frog: General S%inptoms.) 273 " LXV. Pilocarpine, Atropine. (Frog: Heart and Vagus Nerve.) . 273 LXVI. Pilocarpine or Arecoline and Atropine. (Frog: Retinal Cir- culation.) 274 CONTENTS LXVII. LXVIII. LXIX. LXX. LXXI. LXXII. LXXIII. LXXIV. LXXV. LXXVI. LXXVII. LXXVIII. LXXIX. LXXX. LXXXI. LXXXII. LXXXIII. LXXXIV. LXXXV. LXXXVl. LXXXVII. LXXXVIII. LXXXIX. xc. Pilocarpine or Arecoline and Atropine. (Dog, Cat, Eabbit, and Pigeon or Chicken: Pupil.) 275 Pilocarpine, Atropine. (Dog: Blood-pressure, Kespiration, Salivary and Pancreatic Secretions.) 275 Pilocarpine, Arecoline, Adrenaline, Atropine, and Barium. (Dog: Bladder, Intestine, Eespiration, Blood-pressure.) 278 Pilocarpine, Adrenaline, Arecoline, Atropine, Barium. (Spinal Dog: Blood-pressure and Bronchioles.) . . 287 Nicotine. (Frog: General Symptoms.) 300 Nicotine. (Frog: Heart and Vagus Nerve.) 300 Nicotine. (Turtle: Heart and Vagus Nerve.) .... 301 Nicotine. (Turtle: Lungs.) 302 Nicotine, Arecoline, Atropine. (Dog : Blood-pressure, Ees- piration, Limb Volume, Litestinal Contraction.) . . . 304 Nicotine, Adrenaline, Pilocarpine, Atropine. (Dog: Blood- pressure, Intraocular Pressure, Eespiration and Kidney, Spleen or Intestinal Loop Volume.) 307 Nicotine, Adrenaline, Barium. (Dog: Pulmonary Blood- pressure, Carotid Pressure.) 310 Nicotine, Pilocarpine, Atropine. (Dog: Intraocular Nerves, Salivary Glands, Oxygen Consumption, Blood-pressure and Eespiration.) 318 Lobeline. (Frog or Turtle: Heart and Inhibitory Nerves.) 322 Lobeline, Pilocarpine. (Turtle: Lung Tracings.) . . . 322 Lobeline, Adrenaline, Pilocarpine, Tetramethylammonium chloride. (Dog: Bladder Contraction, Blood-pressure, Eespiration, Pupil.) 325 Lobeline, Nicotine, Pilocarpine. (Guinea Pig, Cat, Dog, or Eabbit; Uterus Strip.) 332 Adrenaline, Lobeline, Nicotine, Pilocarpine, Atropine. (Guinea Pig, Eabbit, Dog, Cat, Frog: Intestinal Seg- ment.) . 334 Muscarine, Atrop)ine. (Turtle: Lung Tracings.) .... 336 Physostigmine. (Frog: Heart Tracing.) 337 Physostigmine, Atropine, (Sodium Nitrite). (Frog: Stom- ach Eing.) 337 Physostigmine. (Turtle: Heart Tracing.) 338 Physostigmine, (Adrenaline, Atropine). (Turtle: Lung Tracing.) 338 Physostigmine, Hyoscine, Adrenaline, (Trimethylamine) (Dog: Eespiration, Blood-pressure, Intestinal Contrac- tions.) 339 Adrenaline, Sodium Nitrite, Barium Chloride. (Dog, Cat or Eabbit: Perfusion of Kidney.) 342 CON^TENTS y PAGE XCI. Physostigmiiie, Atropine, (Heroine), Adrenaline. (Spinal Dog or Cat: Bronchioles, Blood-pressure, and Bladder Contrac- tions.) , 346 XCII. Cocaine. (Frog: Central Nervous System.) 350 XCIII. Cocaine, Physostigmine. (Rabbit, Cat, Dog, Pigeon, Sparrow, Chicken, Rat: Action on Pupil.) . . • 350 XCIV. Cocaine, Novocaine. (Local Anesthetic Action.) 351 XCV. Cocaine. (Frog or Turtle: Heart Tracings.) 351 XCVT. Cocaine. (Frog: Action on Muscular Work.) ...... 352 XCVII. Cocaine, Novocaine, Barium, Adrenaline. (Dog or Cat: Res- piration, Blood-pressure, Intraocular Pressure, Local Vascu- lar Action and Intestinal Contractions.) 353 XCVIII. Novocaine. (Dog: Spinal Anesthesia.) 356 XCIX. Ergot. (Rooster: Action on Comb.) 360 C. Ergot. (Frog: Capillary Circulation.) 361 CI. Tyramine. (Frog: Capillary Circulation.) 363 CII. Ergamine. (Turtle: Lung Tracing.) 363 cm. Ergotoxine, Ergamine, Adrenaline, Barium. (Dog or Cat: Blood-pressure, Respiration, Uterine Contractions — Bar- bour's Method.) 363 CIV. Ergamine, Adrenaline, Tyramine, (Codeine or Heroine). (Dog: Blood-pressure, Pulmonary Blood-pressure, Respiration.) . 369 CV. Ergamine, Adrenaline (or Hordenine), Atropine. (Spinal Dog, or Cat: Bronchioles.) 373 CVI. Ergotoxine, Ergamine. (Cat, Guinea Pig, Dog, Rabbit: Uterine Strip.) 380 CVII. Ergot. (Cat: Action on Uterus.) 381 CVIII. Pituitrin, Ergamine, Adrenaline. (Dog, Cat, or Rabbit: Uter- ine Contractions, Blood-pressure.) 382 CIX. Pituitrin, Ergamine, Levulose, Adrenaline. (Dog: Thoracic Duct, Blood-pressure, Bladder Contractions, Resp)iration.) 384 ex. Pituitrin. (Frog: Capillary Circulation.) 387 CXI. Pituitrin. (Frog or Turtle: Heart Tracing.) 388 CXII. Pituitrin. (Turtle: Lung Tracing.) 388 CXIII. Pituitrin. (Guinea Pig, Cat, Dog, Rabbit: Uterine Strip.) . 390 CXIV. Pituitary Extract, Adrenaline, Atropine, Baiium (Dog: Bron- chial Contraction.) 391 CXV. Pituitrin, Adrenaline, Aconitine. (Dog: Urine Secretion, In- testinal Contractions, Blood-pressure, and Respiration.) . 392 CXVI. Pituitrin, Adrenaline, Vanadium. (Dog: Pulmonary Blood- pressure.) 394 CXVII. Dissection of the Eye. — Its Anatomy and Pharmacology . . . 394 CXVIII. Amyl Nitrite. (Student: Plethysmographie Record, General Action.) 397 10 CONTENTS CXIX. cxx. CXXI. CXXII. CXXIII. CXXIV. cxxv. CXXVI. CXXVII. CXXVIII. CXXIX. cxxx. CXXXI. CXXXII. CXXXIII. CXXXIV. cxxxv. CXXXVI. CXXXVII. CXXXVIII. CXXXIX. CXL, CXLI. CXLII. CXLIII. CXLIV. CXLV. CXL VI. CXL VII. CXLVIII. CXLIX. CL, PAGE Amyl Nitrite. (Student: Pulse Tracing.) 399 Amyl Nitrite. (Student: Corpuscles in Retinal Vessels.) 400 Amyl Nitrite. (Student: Retinal Blood Vessels.) . . . 401 Amyl Nitrite. (Student: Effect on Vision.) 403 Amyl Nitrite, Nitroglycerine, Sodium Nitrite. (Dog: Bloodri)ressure, Respiration, Spleen or Intestinal Loop Volume, Blood.) 404 Nitrites, Pilocarpine, Adrenaline. (Dog: Bronchial Ac- tion.) 406 Digitoxin. (Frog: General Action.) 407 Digitoxin. (Frog: Heart Tracing.) • . . 408 Digitoxin. (Turtle: Heart Tracing.) 408 Digitoxin. (Dog or Cat: Blood-pressure and Respiration.) 408 Digitoxin, Strophanthin, Nitroglycerin. (Dog: Pulmonary Blood-pressure, Carotid Pressure.) . ., 415 Digitoxin. (Dog: Heart Tracings, Carotid Pressure.) . . 418 Digitoxin, Strophanthin. (Dog: Diuresis, Spleen Volume, Leg Volume, Blood-pressure and Respiration.) . . . 420 Adrenaline, Potassium Chloride, Digitoxin, Strophanthin. (Cat, Rabbit, Dog: Heart Perfusion — Langendorff Method.) 424 Aconitine. (Frog: General Action.) 428 Aconitine. (Frog: Heart Tracing.) 429 Aconitine. (Turtle: Heart Tracing.) 429 Aconitine. (Dog: Blood-pressure, Respiration, Tempera- ture.) 429 Aconitine. (Dog: Heart Tracings, Blood-pressure.) . . 431 Aconitine. (Student: Local Action.) 433 Veratrine. (Frog: General Action.) 433 Veratrine. (Frog or Turtle: Heart and Inhibitory Ap- paratus.) 434 Veratrine. (Frog: Skeletal Muscle.) 434 Veratrine. (Turtle: Lung Tracing.) 437 Veratrine, Adrenaline. (Dog: Blood-pressure, Respiration, Intestinal Contraction.) 437 Veratrine. (Dog: Heart Tracings, Blood-pressure.) . . 440 Apomorphine. (Dog: Vomiting Center.) 440 Ipecac. (Dog: Eniesis.) 440 Sodium Cyanide, (Hydrocyanic Acid), Sodium Sulphide, Hydrogen Peroxide. (Dog: Respiration, Blood-pres- sure, Oxygen Consumption, Blood Glycosuria.) . . . 441 Quinine. (Frog: General Symptoms.) 447 Quinine. (Frog or Turtle: Heart Tracing.) 447 Quinine. (Frog: Action on White Corpuscles — Binz's Ex- periment.) 447 CONTEXTS 11 PAGE CLI. Antipvrinc. (Frog: General Action.) 449 CLII. Antipyrine, /3-tetrahydronaphtliylamine Hydrochlorido. (Dog: Respiration, Blood-pressure, Leg Volume.) 449 •CLIII. Antipyrine, Peptone. (Two Rabbits: Temperature Regula- tion.) 451 CLIV. Quinine, Peptone. (Two Rabbits: Tem2:)erature Regulation.) 451 CLV. Phenacetine, Acetanilide or Aspirin (Acetylsalicylic Acid). (Fevered Animal: Temperature.) 451 CLVI. Acetylsalicylic Acid (Aspirin). (Student: Headache.) . . 452 CLVII. Phenylsalicylate (Salol). (Student: Excretion, Absorption.) 452 'CLVIII. /3-tetraliydronaphtliylamine Hydrochloride, Pilocarpine. (Dog: Oxygen Consumption, Blood-pressure, Respiration.) . . 45.3 CLIX. Carbolic Acid (Phenol). (Frog: General Action.) . . . 454 CLX. Carbolic Acid, Sodium Sulphate. (Dog: Local Action, Res- piration, Blood-pressure, Spleen Volume, Antidote.) . . 454 CLXI. Phloridzin, Adrenaline. (Rabbit: Glycosuiia.) 457 CLXII. Potassium Iodide. (Student: Absorption, Excretion.) . . 457 ■CLXIII. Alkalies, Acids, Sodium Nitrite, Adrenaline. (Frog: Perfu- sion of Vessels.) 458 CLXIV. Magnesium, Calcium. (Rabbit: Anesthesia, Antagonism. — Meltzer and Auer's experiment.) 460 CLXV. Arsenic. (Dog or Rabbit: Respiration, Blood-pressure, Peri- stalsis, Renal Action, Blood.) 460 CLXVI. Antimony (Tartar Emetic). (Dog: Emesis.) 462 CLXVII. Vanadium, Sodium Hydroxide, Ammonia. (Dog: Blood-pres- sure, Respiration, Spleen Volume, Reflex and Local Ac- tions, Intestinal or Bladder Contractions.) 462 CLXVIII. Acid, Alkali — Rhubarb, Croton Oil, Magnesium Sulphate. (Dog: Antagonism of Acids and Alkalies, Absorption and Excretion of Rhubarb, Local Action of Croton Oil and Magnesium Sulphate — Moreau's Experiment.) . . 466 PAET II. SHOP WORK. The Shop 470 Equipment 476 List of Equipment 479 Mechanical Procedures 489 Glass Blowing 49.3 Frog Clips 495 Brass Arterial Cannulas 496 Stands and Castings 496 Lacquering 49S 12 CONTENTS PHOTOGRAPHY. PAGE II. Photographic equipment 500 Making negatives 502 Lantern slides 505 Making prints 508 Blue prints 510 LIST OF DEALEES. List of Dealers in Equipment and Supplies 515 ILLUSTRATIONS. TIG. ■ I'AGE 1. Harvard inductorium 35 2. DuBois-Reymond induction coil 36 3. Harvard signal magnet 36 4. Signal magnet 36 5. Hale 's signal magnet 36 6. Mercury manometer and signal magnet 37 7. Harvard shielded electrodes 3S 8. Woulff ether bottle with regulating clamp 38 9. Large size tracheal cannula 39 10. Medium size tracheal cannula 39 11. Small size tracheal cannula 39 12. Mohr pinch cocks 40 13. Marey tambour 40 14. Adjustable tambour with three interchangeable bowls 40 15. Stethograph drum 41 16. Kidney oncometer 41 17. Roy's kidney oncometer 42 18. Arterial cannula 42 19. Beaker 43 20. Dog board and mouth rod 43 21. Animal board and head holder 43 22. Small, white evaporating dish 43 23. Glass bladder cannula 44 24. Graduated cylinder 44 25. Casserole 44 26. Harvard long paper kymograph 45 27. Hiirthle long paper kymograph 45 28. Turtle board 46 29. Specimen jar 46 30. Burette and double clamps 46 31. Battery jar 47 32. Small wood tables 47 33. Serrefine . 48 34. Hemostat 48 35. Small sharp-pointed dissecting forceps ... 48 36. Scalpel 49 37. Small aneurism needle 49 38. Large aneurism needle 49 39. Large blunt-pointed dissecting forceps 49 40. Small blunt-pointed dissecting forceps 49 41. Dissecting scissors . 49 42. Dissecting probe (dental) 49 43. Large moderately blunt-pointed dissecting forceps 50 44. Needle holder 50 14 ILLUSTRATIONS FIG. PAGE 45. Large bottle for holding stock salt solution 52 46. Frog board and clip (Harvard) 54 47. Dissection of a frog showing position of the brain, sciatic nerve and arteries and muscles of the hind limb (Color plate) .... 54 48. Frog's brain 55 49. Method of pithing a frog 56 50. Harvard moist chamber 57 51. Harvard muscle lever 58' 52. Harvard gas chamber 58 53. Ether bottles showing method of administering air and ether . . 59 54. Three forms of containers for ethyl chloride 60 55. Method of smoking drums 61 56. Automatic shellacing pan and drying rack for drum records ... 62 57. Varnishing pan for varnishing records 63 58. Print and tracing trimmer 63 59. Method of arranging the inductorium 64 60. Dissection of a frog to show the position of the heart, vagus nerve and the muscles of the hind limb (Color plate) 6.5 61. Diagrammatic dissection to show the innervation of the frog's heart 66 62. Heart lever 66 63. Arrangement of apparatus for recording frog heart tracings ... 67 64. Medicine dropper 68 65. Anatomy of the frog 's heart 69 66. Diagrammatic representation of the lymph spaces of the frog . . 70' 67. Apparatus for recording turtle heart tracings 72 68. Method of sawing out a square in the plastron of a turtle .... 73 69. Diagrammatic representation of the turtle's heart (Color plate) . 74 70. Schematic representation of the vagus and sympathetic nerves in a turtle 75 71. Method of etherizing a dog 77 72. Laboratory table 79 73. Metronome for operating the electric time signal 80 74. Lieb-Beeker time marker made from an Ingersoll watch .... 80 75. Harvard time clock 81 76. Jaquet chronograph 82 77. Two forms of time clocks 82 78. Method of fastening the animal's head to the dog board .... 83 79. Heavy string with slip noose ready to put around the fore limb . . 83 80. Method of attaching fore limbs to the dog board 84 81. Method for quickly fastening the string to the board without tying any knots 84 82. Method of fastening the hind limbs 85 83. Method of incising the skin to expose the trachea 86 84. Same'ks Fig. 83. Separation of borders of sternohyoid muscles . 87 85. Same as Fig. 83. Exposing the trachea 87 86. Same as Fig. 83. Lifting up and passing forceps beneath trachea . 88 87. Same as Fig. 83. Fifth step in the operation 88 88. Same as Fig. 83. Insertion of the tracheal cannula 89 89. Same as Fig. 83. Lifting up right carotid sheath on an aneurism needle 89 ILLUSTRATIONS 15 riG. PAGE 90. Same as Fig. 83. Ligation of the carotid and vago-sympathctic nerve 90 91. Same as Fig. 83. Opening the carotid artery 90 92. Same as Fig. 83. Insertion of the arterial cannula 91 93. Same as Fig. 83. Final step in operation 91 ■ 94. Insertion of femoral injecting cannula 93 95. Dissection to expose the femoral artery and vein and saphenous nerve 95 9(3. Same as Fig. 95. Position and relations of the vein, artery and nerve 95 97. Exposure of the skull for a trephine opening 103 98. Six inch tinner's snips. For cutting thick skin and fascia, etc. . 104 99. Same as Fig. 97. Exposing dura mater 104 100. Trephine 105 101. Upper surface of a dog's brain 106 102. "Straight" glass cannula . 107 103. Hand bellows 107 104. Bandage saw 108 105 Method of opening the chest by a median incision 109 106. Method of exposing the left pulmonary artery and vein (Color plate) 110 107. Applying the cardiometer over the ventricles Ill 108. Cardiometer .112 109. Administration of nitrous oxide or oxygen to a frog 114 110. Method for making, purifying and administering nitrous oxide to a frog 115 111. Yoke for tanks of oxygen, nitrous oxide or carbon dioxide- . . . 115 112. A double yoke for holding gas tanks 116 113. Yoke for holding igas tanks 116 114. Guthrie's carbon dioxide generator 117 115. Method for studying the action of nitrous oxide, ethyl chloride, etc. . . . '. 118 116. Apparatus used for closed ether anesthesia 122 117. Table arranged for performing an experiment 123 118. Diagrammatic view of the pan as seen from above 124 119. Tracing obtained by the closed method of anesthesia 125 120. Tracing showing the initial action of nitrous oxide 126 121. Tracing showing the action of nitrous oxide and ethyl chloride . 127 122. Apparatus for intratracheal insufflation 129 123. Apparatus for administering nitrous oxide to an animal .... 130 124. Tracing showing action of carbon dioxide 131 125. Injection of drug solutions into anterior lymph sac of frog . . 134 126. Injection of solutions into anterior lymph sac with a syringe . 134 127. Injecting pipette made of glass 135 128. Arrangement of apparatus for recording esoi^hageal contractions 137 129. Tracing showing four esophageal contractions, blood-pressure and respiration 138 130. Harvard membrane manometer 139 131. Arrangement of apparatus which may be used as a membrane manometer 141 16 ILLUSTKATIONS FIG. PAGE 132. Tracing showing action of alcohol on blood-pressure and respira- tion 142 133. Dissection showing vessels and nerves in the neck and upper part of the chest in a dog (Color plate) 142 134. Arrangement of apparatus for recording reaction time for sight . 143 135. Simple key 145 136. Electric tuning fork 145 137. Apparatus for recording reaction time for hearing 146 138. Box for anesthetizing cats 147 139. Bell-jar as used for anesthetizing cats 148 140. Glass or earthen ware jar covered by a glass plate 148 141. Myocardiograph 149 142. Cardiometer arranged for use as a myocardiograph 150 143. Cardiometer made from a large thistle tube 151 .144. Arrangement of apj)aratus for recording heart tracings .... 152 145. Special heart holder 153 146. Heart levers for dogs 154 147. Schematic representation of the innervation of the heart (Color plate) 154 148. Innervation of heart in the cat 155 149. Myocardiographic and blood-pressure tracings from a dog . . . 156 150. Fermentation tube 157 151. Apparatus for recording the pressure of the cerebrospinal fluid . 159 152. Spleen oncometer for dogs 160 153. Spleen oncometer for dogs 161 154. Kidney oncometer 162 155. Rear view of same oncometer shown in Fig. 154 162 156. Kidney oncometer made of a metal pill or ointment box .... 163 157. View showing the oncometer partly open 163 158. Dissection exposing the kidney from a median incision .... 164 159. Arrangement of apparatus for making several records simulta- neously 165 160. Appearance of the blood-vessels in the ears of a white rabbit (Color plate) 166 161. Dissection showing position of left pulmonary vessels and sympa- thetic trunk in chest above diaphragm (Color plate) .... 166 162. Dissection to show the abdominal viscera (dog) 167 163. Electric ophthalmoscope 170 164. Method used for observing the retinal circulation in a frog . . . 171 165. Ventral and dorsal views of a pigeon's brain 173 166. Posterior view of the bi'ain and semicircular canals of a pigeon . 174 167. Lateral view of head of pigeon showing brain, etc 174 168. Base of the brain of a dog 175 169. Upper surface of the skull of a cat 178 170. Mesial section showing the left half of the interior of a cat's skull 179 171. Dorsal surface of the brain of a cat 180 172. Apparatus for recording and measuring the rate of oxygen con- sumption 181 173. Inner construction of the pans shown in Fig. 172 182 174. Lateral view of a cross-section of the apparatus shown in Fig. 172 182 ILLUSTRATIONS 17 FIG. PAGE 175. Arrangement for recording oxygen consumption by an animal . 1S3 176. Apparatus used for making pure oxygen 185 177. Gas reservoir made from a very shallow, wide, round cake pan . 180 178. Dreser's apparatus for respiratory measurements 187 179. Teclinic for inserting a bladder cannula 188 180. Tracing showing action of morphine on oxygen consumption . . 191 181. Eecord showing the action of adrenaline on the rate of oxygen consumption, uterine contractions, blood-pressure and respira- tion 192 182. Schematic representation of the course of the right phrenic nerve in a dog 193 183. D.issection of lower part of neck and upper part of chest on right side in dog (Color plate) 194 184. Dissection of lower part of neck and upper part of chest and of axillary region in dog (Color plate) 194 185. Large needles for sewing with heavy twine 195 186. Brass tube with spear point . 196 187. Arrangement of animal for recording lung volume changes . . . 196 188. Apparatus for keeping the systematic blood-pressure at a con- stant level 197 189. Lung volume and blood-pressure record 198 190. Tracings showing the action of morphine 199 191. Tracings showing the action of pantopon 200 192. Tracings showing the action of peronine 201 193. Tradings showing the action of dionine 202 194. Tracings showing the action of narcotine 203 195. Tracings showing the progressive actions of narcophine, narcotine and morphine 204 196. Method of administering capsules, pills or tablets to dogs . . 205 197. Merctry bulb 206 198. Apparatus for recording bladder contractions 207 199. Same as Fig. 198. Dissection for the femoral vessels .... 208 200. Lung shield made of thin sheet brass 209 201. Method of recording volume changes of the lung by use of the lung shield 210 202. Tracing showing action of heroine and adrenaline 212 203. Tracing showing the action of codeine and epinine 213 204. Tracing showing the action of muscarine 214 205. Tracing showing the action of codeine on turtle 's lungs . . . 215 206. Three kinds of catheters 216 207. Dissection of the pelvis of dog 216 20S. Arrangement of apparatus for recording convulsions in a frog . 218 209. Tracing showing the action of strychnine 219 210. Greene's method of irrigating the heart 221 211. Tracing showing the action of strychnine on the turtle's heart . 222 212. Glass oncometer for a small loop of the intestine 223 213. Glass ureteral cannula Avith rubber tube connection 225 214. Tracing showing the action of morphine 228 215. Tracings showing the action of picrotoxine 232 216. Tracings showing the action of brucine 233 18 ILLUSTEATIOI^S FIG. PAGE 217. ]V[etliod of administering medicine to a dog by means of the stom- ach tube , . . . 234 218. Mouth gag for dogs, cats or rabbits 235 219. Dissection to expose the sciatic nerve 237 220. Method of destroying the cerebrum only in a frog 238 221. Tracing showing action of hydrastine 239 222. Innervation of the heart in the frog or turtle 240 223. Tracing showing the action of arecoline, hydrastinine and ad- renaline 242 224. Arrangement of a frog and ajjparatus for recording fatigue trac- ings 245 225. Showing a method for making cannulas with separable point-s . . 246 226. Structures in the neck of a rabbit showing the arrangement of the nerves on the left side (Color plate) 247 227. Glass cannula showing a special washout opening 248 228. Arrangement of two tambours to form a drop recorder .... 250 229. Tracing showing action of sodium sulphate 251 230. Tracing showing the action of curara 256 231. Innervation of the salivary glands in the dog (Color plate) . . 257 232. A turtle prepared for recording lung tracings 261 233. Arrangement of apparatus for recording lung contractions . . . 262 234. Lung tracing from a turtle 263 235. Lung and heart tracings from a turtle 264 236. Diagrammatic representation of innervation of lachrymal glands 265 237. First incision for exposing the chorda tympani nerve, etc. . . . 266 238. Dissection showing position and relation of hypoglossal and lin- gual nerves (Color plate) 266 239. Exposure of the ling-ual and hypoglossal nerves and salivary ducts (Color plate) 266 240. Exposure of the chorda tympani nerve (Color plate) .... 266 241. Tracing showing the action of pilocarpine 274 242. General course of the nerves to the salivary glands (Color plate) 274 243. The submaxillary and sublingual glands and their ducts, etc. (Color plate) 274 244. A dissection showing position and relations of pancreatic ducts in dog 276 245. Position and relations and method of isolating large duct of pancreas in dog (Color plate) 278 246. Arrangement of apparatus for recording contractions of intestine. 279 247. Tracing showing the action of barium, adrenaline and atropine . 280 248. Tracing showing action of barium and adrenaline 281 249. Tracing showing the action of arecoline and of atropine . . . 282 250. Innervation of the retractor penis muscle (Color plate) .... 282 251. Tracing showing the action of pilocarpine 283 252. Tracing showing the action of a fatal dose of barium chloride . 284 253. Tracing showing the action of adrenaline and barium chloride . 285 254. Tracing showing the action of a fatal dose of barium chloride . 286 255. A form of apparatus used in recording lung tracings 288 256. A form of apparatus used in recording lung tracings .... 289 ILLUSTRATIONS 19 FIG. PAGE 257. Adjustment of the apparatus shown in Fig. 25.5 in the chest of a dog 290 258. Method of making the first incision before trephining tlie skull . 292 259. The trephine opening 292 260. Method of quickly cutting across the brain stem 293 261. Method of destroying the brain 293 262. Plugging trephine opening with cotton after brain is destroyed . 294 263A. Tracing showing the action of pilocarpine and atropine . . . 295 263B. Tracing showing the action of muscarine and atropine .... 295 264. Tracing showing the action of lodal 296 265. Tracing showing the action of arecoline 298 266. Tracing showing the action of arecoline and atropine .... 299 267. Tracing showing the action of nicotine 301 268. Tracing showing the action of nicotine 303 269. Method of applying a plethsmograph to the hind leg of a dog . 304 270. Tracing showing the action of a fatal dose of nicotine .... 305 271. Arrangement of apparatus for recording intraocular pressure . 308 272. Tracing showing the action of nicotine 309 273. Arrangement of apparatus for recording pulmonary blood-pressure 311 274. Dissection showing the method of ligating the left pulmonary artery 312 275. Second step in preparing to insert a cannula in the pulmonary artery 312 276. Third step in preparing to insert a cannula in the pulmonary artery 313 277. Method of inserting the special cannula iiito the artery .... 313 278. Special form of separable pointed cannula for pulmonary artery . 315 279. Special (all-glass) form of cannula for the pulmonary artery . . 315 280. Tracing showing the action of adrenaline 317 281. Method of dissecting out the orbital fat and fascia to expose the optic nerve 319 282. Bone cutting forceps 320 283. Tracing showing the action of lobeline, arecoline and atropine . 323 284. Tracing showing the action of lobeline 324 285. Tracing showdng the action of lobeline 324 286. Tracing showing the action of pilocarpine 325 287. Tracing showing the action of lobeline . 326 288. Tracing showing the action of lobeline 327 289. Tracing showing the action of tetramethylammonium chloride . 329 290. Tracing shownng the action of tetramethylammonium chloride . 330 291. Tracing showing the action of pilocarpine, and tetramethylam- monium chloride 331 292. Arrangement of apparatus for recording contractions from a uterine strip, or from an arterial ring, ureter ring, intestinal strip, ring of frog's stomach, etc. 333 293. Tracing showing the action of muscarine 335 294. Diagrammatic cross-section of the intestine (Color plate) . . . 336 295. Tracing showing the action of nicotine, arecoline and atropine . 336 296. Tracing showing the action of trimethylamine 340 297. Tracing showing the action of pilocarpine and trimethylamine . 341 20 ILLUSTRATIOIsTS FIG. Px'^GE 298. Arrangement of apparatus for perfusion of an excised organ . . 343 299. Tracings showing action of sodium orthovanadate, barium chlo- ride, and adrenaline 345 SOOt. Tracing showing the action of heroine and adrenaline .... 348 301. Tracing showing effects of cocaine 352 302. Method of exposing the lymphatic ducts and connecting cannulas to collect the lymph or chyle (Color plate) 356 303. Metallic muzzle for administering an anesthetic to a dog . . . 357 304. View of the reverse side of the metallic muzzle shown in Fig. 303 358 305. Arrangement of apparatus for observing the capillary circulation 362 306. Arrangement of animal and apparatus for recording uterine con- tractions 364 307. Tracing showing the action of barium chloride 365 308. Tracing showing the action of ergamine (histamine) and adrena- line " . 307 309. Tracing showing the action of ergamine 368 310. Tracing showing the action of tyramine 370 311. Tracing showing the action of adrenaline and ergamine . . . 372 312. Tracing showing the action of ergamine and hordenine . . . . 376 313. Tracing showing the action in succession of arecoline, lodal, the- baine, lodal, hordenine and adrenaline 377 314. Tracing showing the consecutive actions of ergotoxine phosphate, pilocarpine, (ergotoxine) and adrenaline 378 315. Tracing showing the action of areeoline, ergotoxine, farecoline) and adrenaline 379 316. Arrangement of apparatus for recording contractions of a uterine strip, intestinal strip, etc 381 317. Arrangement of apparatus for recording contractions of the uterus in situ 382 318. Schematic representation of the involuntarj^ nervous system (Color plate) 384 319. Method of isolating the thoracic duct at the root of the neck (Color plate) . 384 320. Diagrammatic representation of the! lymphatic system in a cat . 386 321. Tracing showing the action of pituitrin 388 322. Tracing showing the action of pituitrin 389 323. Tracing showing the action of pituitrin 391 324. Schematic representation of the innervation of the eye (Color plate 394 325. Diagrammatic representation of the structure and innervation of the eye (Color plate) 394 326. Plethysmograph for recording volume changes in hand and fore- arm 398 327. Dudgeon's sphygmograph arranged for recording tracings from the radial pulse 399 328. Tracing showing action of amylnitrite 400 329. Tracing showing the action of nitroglycerine 405 330. Tracing showing the action of digitoxin 409 331. Tracing showing the action of digitoxin 410 332. Tracing showing the action of digitoxin 411 ILLUSTRATIONS 21 FIG. PAGE 333. Tracing showing tho action of cligitoxin 412 334. Tracing showing the final result of the action of digitoxin . . 413 335. Illustration showing principles involved in construction of Ed- munds' liver oncometer 416 336. Tracing showing the action of adrenaline 417 337. Spleen oncometer made of crimped sheet brass 421 338. Liver oncometer 422 339. Tracing showing the action of tetramethylammonium chloride . 423 340. Arrangement of apparatus for recording tracings from an excised heart 425 341. Cat's heart 426 342. Dog's heart 427 343. Tracing showing the linal action of aconitinc 432 344. Tracing showing the action of veratrine .......... 435 345. Arrangement of apparatus for spinning a drum 436 346. Tracing showing the action of veratrine 438 347. Tracing showing the action of sodium cyanide 442 348. Tracing showdng the action of potassium cyanide 443 349. Tracing showdng the action of sodium cyanide 444 350. Tracings showing the action of dilute sodium cyanide solution . 445 351. Tracing showing the action of pilocarpine and (3-tetrahydronaph- thylamine hydrochloride 450 352. Two tracings showing the action of a drug which markedly lowers blood-pressure 455 353. Arrangement of apparatus for perfusion of the vessels of a brain- less frog 459 354. Tracing showing the action of adrenaline sodium orthovanadate, amylnitrite and adrenaline 463 355. Tracing showing the action of vanadium 464 356. Tracing showing the action of vanadium 465' 357. Arrangement of the ligatures for isolating segments of the in- testine 467' 358. A schematic representation of an electric wiring system .... 471 359. Foot bellows . 472^ 360. Diagrammatic representation of an artificial respiration machine 473'' 361. View of system of pulleys used to operate the interrupting valve 474 362. Lever gate valve 474 363. Diagram showing method of operation of lever gate reversing valves 475 364. Portable artificial respiration machine 475 365. Special form of interrupting valve 476 366. Special interrupting valve 477 367. A motor driven long paper kymograph 478 368. Detailed view of one plan of construction of the speed regulating- device for the kymograjDh 479 369. Motor driven long paper kymograph 480 370. Hand drill 481 371. Blast lamp 482 372. Details of the mechanical construction of an adjustable tambour 483 373. A large bowled tambour 484 22 ILLUSTRATIONS FIG. PAGE 374. Method of tying head of a small screw into rubber niembrane . 484 375. Some of the more common types of gas pipe fittings 486 376. Small electric heater 487 377. Method of preparing two pieces of brass tnbing for making a tracheal cannula 490 378. Method of making "straight" glass cannulas 492 379. Same as Fig. 378 492 378 ........ 492 381. Same as Fig. 378 494 382. Same as Fig. 378 . 494 making frog clips 495 making very small brass cannulas ....... 496 385. Large stand with L-shaped base ; . . 497 386. Method of arranging the camera and. arc light for copying . . 501 387. Method of suspending an adjustable are light above the operating table 502 388. Measuring glass 504 389. Adjustable frame for cutting lantern slide mats 507 390. Frame for making blue prints 511 383. Process for 384. Method for INTRODUCTION. The unit of procedure adopted in this manual is the ex- periment. Each experiment is, as a rule, complete within itself, although in many instances an orderly sequence pro- ceeding from the simple to the more complex, from the known to the unknown, has been introduced. The writer has at all times tried to hold in mind the fact that the in- structor is not only teaching i)harmacology but that he is also teaching medical students. And the mental and tech- nical abilities and limitations of these students are quite as significant from the standpoint of the teacher as is the wide extent, the complexity, and the importance of the sub- ject which he practically invariably has a too limited time to cover. It is constantly necessary for the teacher of pharmacology to bear in mind that the knowledge which his students possess of the fundamental principles of anat- omy, neurology, physiological chemistry, pathology, and especially of physiology, is by no means complete, and much of the instructor's time must of necessity be consumed in again bringing to the attention of the students fundamental and often exceedingly elementary facts invoh^ed in the nature of subjects prerequisite to the course in pharma- cology. And it will not infrequently severely tax the in- genuity of the teacher of pharmacology to determine by what means he can, within a brief period of time, best recall to the student's mind some fundamental princij)les, e. g., of iDhysiology or neurology, without a knowledge of which further progress in pharmacology is totally impos- sible. The author has kept these points carefully in mind in preparing this manual, and many of the exjDeriments, illustrations and tracings have been introduced quite as much with the object of teaching certain fundamental prin- 24 IJ^TRODUCTIOIS;" ciples of anatomy, chemistry, physiology, etc., as for their immediate use in the work on pharmacology. It has been the author's aim to try to develop experimen- tally a knowledge of the general principles of pharmacolog- ical reactions, rather than to lay great emphasis on a vast array of details regarding the specific action of a long list of substances. There are more than 100,000 known organic preparations, with many more theoretically possible. In ad- dition to this there are some 3,000 or 4,000 inorganic sub- stances, salts, etc. A very large proportion of these bodies might be studied separately and individually so far as their pharmacological properties and reactions are concerned. And if we attempt to have our students make a fairly in- tensive study of only the one-thousandth part of all this vast array of chemical substances, the task is still so great that perhaps no human mind can grasp and carry within the memory at any one time the almost limitless extent of the specific details of the pharmacological reactions of which even this comparatively small number of drugs may theoretically be caj)able. And notwithstanding the more or less abortive attempts of nearly all recent writers and examining boards, to limit as far as possible the number of drugs which the student must study, the task of selection is still largely one for the individual instructor. The experiments listed herein are, as a rule, arranged with reference to individual drugs. The simplest and easiest experiments on any given substance are usually placed at the beginning of the section dealing with that body. Being keenly aware of the difficulty often experi- enced in obtaining suitable experimental material the author has included a large number of experiments on frogs and turtles, the supply of Avhich is less liable to variation than is that of the vastly more desirable mammalian ma- terial. Generally a number of experiments are given on each drug, especially if it be one of importance. It is in- tended that these experiments be assigned to the students INTEODUCTION" 25 on the day before the experiment is to be performed in order that each member of the class may familiarize himself with the work he is expected to do. Many of the experiments may be done as demonstrations. It is usually advisable for each group to do a different experiment at any given labora- tory period. This economizes on the amount of special apparatus required and also furnishes an opportunity for each group of students to compare its results with those obtained by the other groups. This arrangement also gives an opportunity for the instructor to devote most attention to those experiments where help is most needed. The general anesthetics, being of fundamental impor- tance for the progress of the course, are taken up first. Following this is a group of drugs chiefly characterized by their action on the central nervous system. After these come a series of substances possessing specific actions on some one or more parts of the involuntary nervous system. These are followed by drugs which act mainly on the cir- culatory system, then follow the antipyretics, a few mis- cellaneous drugs, and finally a few experiments on acids, alkalies, and some of the heavy metals. The second part of the book contains two chapters, one on shop Avork and one on i^hotography. These are chiefly of interest to the instructor, and it is advised that these be read in connection with the general preparation of appa- ratus, equipment, etc., for the course in pharmacology. Any general text book on the subject of pharmacology may be used in connection with this manual, or if the in- structor prefers to deliver a course of set lectures on the general field of pharmacology, no didactic text at all may be required. That is a matter for each teacher to decide for himself. Usually drugs are taken up one at a time. It is desir- able not to confuse the student more than can be helped by the introduction of too many drugs, especially if the actions of the drugs involve general pharmacological iDrin- 26 INTRODUCTIOISr ciples with which the student is unfamiliar. It often oc- curs, however, that as the student gains in experience and in technical ability, drugs which have already been studied may be reintroduced either as a matter of review, or to demonstrate certain actions of other drugs which are not •evident until brought to light by the changed response of certain structures to drugs injected secondarily, or to serve ■SiS a check on the action of the apparatus and the general technic employed in the experiment. For this latter pur- pose great use is made of adrenaline in these experiments. This often serves the double purpose of reviving an animal Avhen it is in a very feeble condition, and also gives the ■student {and instructor) an immediate indication of the accurary of the working of his apparatus and of the condi- tion of the animal. It should be especially emphasized that the extensive use made of adrenaline in many of the ex- periments is solety for the purposes here indicated, and its frequent injection should not be considered in any sense as --a useless repetition of the same experiment. It is imperative to use the strictest economy Avith the ex- perimental material. For this reason it is desirable for the students to learn everything possible from each animal used. Consequently many experiments are listed here in ivliich a variety of reactions may be recorded at the same time. The instructor should use his judgment in the case of each group of students regarding the number of records which the group will probably l)e able to successfully se- cure. And he should not hesitate to eliminate any indicated part of the experiment in which he believes the group will fail. The author has, however, often been amazed at the excellent success which students with some experience may frequently obtain in carrying out exceedingly difficult and involved experiments. And the writer recommends that the instructor should not hesitate to permit a group of students to attempt to carry out a difficult experiment ^whenever he can advisedly do so. For it should be espe- cially emphasized that a student's own failure may be of IJSTTRODUCTION" 27 vastly more interest and value to him than would he a per- fect success of that same experiment demonstrated by the instructor or his assistants. Many instructors advise that each student in the group take his turn at doing various jiortions of the routine work. In the writer's opinion this will probably not be the most valuable line of procedure in the long run. For while it may be very desirable for each student to acquire a certain amount of skill in performing each part of the experiment (and students usually want to do this at the start) the fact remains that the total time devoted to the subject is too short for any student to become an expert in carrying out all phases of the work. It will yield a greater percentage of pharmacological successes for each student to learn a given portion of the routine work well and to faithfully carry this out for each experiment. It should be empha- sized that the chief object of the experimental course is not to teach surgery, but pharmacology. For while students may, and in a thoroughly satisfactory course perhaps do, acquire a very fair amount of the knowledge of surgery which they Avill later possess, this should be looked upon solely as a matter of secondary imjoortance. Practice dissections on dead animals are frequently de- scribed at the end of experiments. This is a matter of great importance and the instructor can often be of much help to the student by aiding in this work to see that it is properly done. These dissections usually precede experi- ments in which the dissected structures will be concerned. A few Avords may be said about the matter of dosage. T^his is a difficult subject and the writer has been compelled to depend mainly on his own records and experience in this line, for most of the published dose tables, etc., are based on quantities of the drugs to be given by mouth. A further difficulty arises from the great variation in the size and re- sistance of different animals, and from the variation in potency of the different drugs as purchased in the open 28 INTEODUCTIO:?^ market. The instructor is advised to make all the observa- tions he can on this subject for the benefit of his students. One of the most valuable things which a course in ex- perimental pharmacology can offer to a student is the very great opportunity which is presented to develop his power to think, to observe, and to learn at first hand for himself. In nearly all of the experim.ents questions are asked which are intended to direct his attention to the most vital and important features of the work, and to encourage him to test out experimentally the truth or falsity of his own conclusions. Every student of modern medicine must have been im- pressed at some time in his Avork by the very great aid which he has derived in his study of anatomy or neurology or operative surgery from the use of illustrations, dia- grams, etc. These are frequently of the greatest use for rapidly reviewing work over which one has long since passed, or for quickly advancing one 's knowledge into fields with which he may be less familiar. The author has care- fully considered this phase of the subject in writing the present manual. And numerous illustrations, tracings, dia- grams, etc., have been devised and presented with the spe- cial object of enabling the student, teacher or practitioner of medicine to quickly and accurately grasp the full mean- ing and significance of important actions of the drugs con- sidered. To one who already possesses a moderate famil- iarity with the subject of modern pharmacology, a brief glance at the nature of mau}^ of the experiments presented, together with a rapid study of the accompanying tracings, may reveal the character and results of the effects which follow the application of drugs to the animal organism with a vividness Avhieh can be exceeded only by the knoAvledge acquired by the actual performance of the experiments themselves. Finally it may be stated that originality and individu- ality, not only for the student but for the instructor as well. INTEODUCTIOlSr 29 should be encouraged in every way possible. For experi- mental pharmacology covers a wide range, and there is at present perhaps no phase of the whole field of medicine which promises more for the future alleviation of human suffering than does this, in a sense one of the oldest, and yet one of the newest of all the divisions of medical science. A NOTE TO THE STUDENT. When pursued under satisfactory conditions experi- mental pharmacology is one of the most valuable and in- teresting of all medical subjects. The province of this AVork is comparatively new, and unfortunately so far as the medical student is concerned, is but poorly developed. The student, as well as his teacher, will feel these limita- tions mainly in the lack of suitable apparatus and perhaps in many cases in a lack of sufficient experimental materiaL The apparatus as a rule is very expensive and usually is obtained only with considerable difficulty, while in a large number of instances equipment suitable for the perform- ance of many of the most valuable and interesting experi- ments must be made up according to special directions. From this it is perfectly obvious that no two schools can expect to possess exactly the same kind of apparatus for the performance of any given series of experiments. The student will often find it necessary to carry out his work with apparatus entirely different from that described in the text and often perhaps with an equipment which is exceedingly unsatisfactory. He should by no means be discouraged thereby, for much of the most valuable ex- perimental work of all history has been performed with crude and unwieldy apparatus, and often under most dis- couraging circumstances. To accomplish much A\dth little is a sure sign of ability and the medical student who ap- proaches the subject of experimental pharmacology at the present time Avill find numerous opportunities to demon- strate his aptitude in this direction. He should seize these opportunities Avith keenness and alertness and with a full appreciation of the advantage which he possesses over that of the medical student who may have been taught ex- perimental pharmacology some ten or fifteen years ago. 32 A NOTE TO THE STUDENT Each experiment in this book Avas designed primarily to give the student an opportunity to learn to think, and sec- ondarily to teach him some valuable point in connection with the drugs studied. The writer full}^ appreciates that there are certain difficulties and limitations beyond which the average medical student can not go, and for the satis- factory performance of the following experiments there has been assumed a certain standard of attainment which to the author's mind represents approximately that de- gree of training which the average sophomore student at the present time should have had when he takes up the study of experimental pharmacology. The student mil feel constantly the necessity of drawing extensively upon his knowledge of anatomy, neurology, and physiology, and to a less extent upon his training in chemistry, physiolog- ical chemistry, pathology, bacteriology, and physics. And he must bear constantly in mind the practical clinical ap- plication and action of the great majority of the drugs with which he will experiment. EXPERIMENTAL PHARMACOLOGY PART I. PRELIMINARY EXERCISE. Assignment of Tables and Permanent Apparatus. At a time previous to the first laboratory meeting if pos- sible the students will arrange themselves according to instructions into groups of four or five each. It is gener- ally desirable (especially if the students are unknoAvn to the instructor) for the students to arrange these groups themselves. This should usually be done with due con- sideration of the relative degree of progress and of abilit};^ which each student possesses, students of approxi- mately equal standing being grouped together. This is a matter of considerable importance to the student, for no one cares to drag a poor student through several weeks of difficult experimentation, Avhile on the other hand the poorer students should not be cheated out of their opportunities to learn because other more compe- tent students do all of the work. The average of the grades which the students have received in previous courses is usually a fair basis for forming these groups. For mammalian experiments students work in the groups of four or five (rarely three or six under special condi- tions). Each group of four (or five) is subdivided into sub-groups of two (or two and three) for work on frogs, turtles, etc. Each group of students will be assigned to a table (or locker) in which the permanent apparatus of the group is already placed and is in perfect working condition. This 34 EXPERIMENTAL PHARMACOLOGY apparatus should he checked up quickly, and all omissions or imperfections should he reported to the technician for correction. A tj^pewritten list of the apparatus will be given to each group. Each piece of permanent apparatus be- longing to a given table is marked plainly with the num- ber belonging to that table to prevent loss. The perma- nent list includes : 2 Simple keys (Fig. 135) 2 Heart levers (Fig. 62) 2 Stimulating electrodes (Fig. 1) 2 Sewing needles 2 Signal magnets (Figs. 3, 4, and 5) 2 Induction coils (or 1 induction coil with a double pole, double throw knife,. switch, Fig. 1) 1 Manometer with signal magnet base line marker and tubing (Fig. 6) 1 Ether bottle, tubing and Hoffmann screw clamp or 1 anesthetic device with oxygen tank, burette, pinch clamps and tubing (Fig. 8) 3 (or 4) Tracheal cannulas (Figs. 9, 10, and 11) 8 Mohr's pinch clamps (Fig. 12) 3 Eecording tambours with T-tubes and tubing (Figs. 13 and 14) 1 StethOgraph drum (Fig. 15) 1 (or 2) Oncometers, T-tubes and tubing (kidney, s]Dleen, or intestinal loop^ see Figs. 16 and 17) 2 Frog boards' (Fig. 46) 2 (to 4) Burettes, tubing and one funnel (small) 1 Large double clamp (to hold frog board, etc.) 4 (or 5) Large stands (Fig. 94) 2 Small stands 1 Pressure bottle, tube, rope and pulley (Fig. 6) 1 Dozen frog clips (Fig. 46) 1 Ball small twine 1 Ball heavy twine 1 Pad of absorbent cotton (a 3-iuch section cut from a 1 lb. roll with a large sharp knife) 2 (or 3) Arterial cannulas (see Fig. 18). More may be needed 2 Beakers, 25 and 50 cubic centimeters (Fig. 19) 2 Small flasks 1 Tube for respiration faucet (for artificial respiration) 1 Dog board with mouth rod (Fig. 20) 1 Thermometer 1 Heart oncometer (cardiometer) (Fig. 108) 1 Small white evaporating dish (Fig. 22) 1 Bladder cannula (Fig. 23) 1 Sj)ool white thread (heavy) 2 Medicine droppers (Fig. 64) 1 Injecting pipette for frogs (Fig. 127) 1 Graduated cylinder, 50 cubic centimeters (Fig. 24) 1 Porcelain dipper (casserole) (Fig. 25) LIST OF APPARATUS OO 8 Pieces insulated connecting wire (No. 18) 2 Kymographs (Harvard) with 4 fans each (or long paper kymographs, Figs. 26 and 27) 2 Turtle boards (Fig. 28) 1 Specimen jar (Fig. 29) 6 Double clamps (Fig. 30) 4 Burette clamps (Fig. 30) 1 Battery jar, 4-inch (Fig. 31) 6 Test tubes 2 Small tables, 3 inches and 4 inches in height (to support kymographs, Fig. 32) 1 Test tube brush 1 Pound of ether Each student will sign the foUomng statement at the bottom of the typewritten list: ''We, the undersigned, have received the above apparatus in good condition, ex- cept as noted, and for which we each stand responsible to the department. Date Signed 1 4 2 5 3 6 " Fig. 1. — Harvard inductorium with dry cell and simple key in series. In the sec- ondary circuit is a double pole double throw knife switch to which are connected two platinum electrodes. By use of this combination two groups of students can use one inductorium and dry cell without either group disturbing the apparatus of the other group. 36 EXPERIMENTAL PHARMACOLOGY <: ■■niMiiii- Fig. 2. — Du Bois Reymond induction coil. Fig. 3. — Harvard signal magnet. Fig. 4. — Signal magnet. :^:^^:^^$^^^^^^^>^?::^^ Fig. 23. — Glass bladder cannula, nearly natural size. Fig. 24. — Graduated cylinder. Fig. 25. — Casserole. LONG PAPER KYMOGRAPHS 45 Fig. 26. — Harvard long paper kymograph. Fig. 27. — Hiirthle long paper kymograph. 46 EXPERIMENTAL PHARMACOLOGY Fig. 28. — Turtle board, made of cheap, scrap, pine lumber (old goods boxes). A hooked wire (sharpened) is attached to the front end. The hook catches in the lower jaw ("chin") of the turtle. The feet are tied out tightly to the staples. Fig. 29. — Specimen jar. Fig. 30. — Upper picture, burette clamp; lower picture, double clamp (Harvard). BATTERY JAR^ SMALL TABLES 47 Fig. 31. — Battery jar (4x5 inches). Fig. 32. — Small wood tables for supporting apparatus, Harvard kymographs, etc. 48 EXPERIMENTAL PHARMACOLOGY Each student should provide himself with a dissecting- gown, a cheap note book for rough notes, and the follow- ing dissecting instruments : 1 (or 2) Serrefins (bull-dog artery clamps) (Fig. 33) 1 (or 2) Hemostats (Fig. 34) 1 Pair small sharp-pointed straight forceps (Fig. 35) Fig. 33. — Serrefine. Fig. 34. — Hemostat. r ^i^li-VMW.i'^/'Mlllnuat Fig. 35. — Small sharp-pointed dissecting forceps. In addition to this, eacli group of students should further provide itself with the following instruments for use of the group as a whole : 2 Good dissecting scalpels. (There is only a very limited use for the knife, hence not more than two need be provided. This may prevent many poor dissections and bad hemorrhages) (Fig. 36) 2 Aneurism needles (Figs. 37 and 38) 2 Pairs of large blunt-pointed dissecting forceps (Fig. 39) 1 Pair of smaller blunt-pointed dissecting forceps (Fig. 40) 3 Pairs of dissecting scissors, one large, two small (Fig. 41) 2 Dissecting probes (Fig. 42) 1 Large moderately sharp-pointed dissecting forceps to be used for inserting cannulas (Fig. 43) DISSECTING INSTRUMEJSTTS 49 Fig. 36. — Scalpel ^- i -' ~ . -^ ^^-t-J^'^V^^'.k^S-k.i^ki.Kkt.^^^.J^^^k^^^kl-iJJk^.^ 'l to,^^^ Fig, 37. — Small aneurism needle. Fig. 38. — Large aneurism needle. dmnm (^uvv^^.^.^.^.^.w^v.^^^^-^^^v-^^^^^^-.-.^^v■^^\\\v■v\^^.^.^v^^\' Fig. 39. — lyarge blunt-pointed dissecting forceps. ^^^^^^SS^^N^^^^W? i"r'7#") Fig. 40. — Small blunt-pointed dissecting forceps. Fig. 41. — Dissecting scissors. Fig. 42. — Dissecting probe (dental). 50 EXPERIMENTAL PHARMACOLOGY Students are warned not to buy the so-called "sets" of dissecting instruments. Also do not buy a lot of unneces- sary instruments. Students who have had human dissec- tion will usually already possess most of the necessary (and a good many unnecessary) instruments. Each student must be provided with a permanent note book in which is written up a careful description of each experiment performed. This note book should be well bound, its dimensions should be about 7% inches b}^ 10^/4 inches, and it should contain about 150 pages. The paper should be of good quality and all permanent notes must Fig. 43. — L,arge moderately blunt-pointed dissecting forceps. Fig. 44. — Needle holder. be written in ink. Avoid typewritten or loose leaf note books. Either the original or blue print copies of all typ- ical tracings obtained should be pasted in the permanent note book and fully explained in the notes. It is urged that notes be made brief, but strictly to the point. It requires only a few paragraphs for a student who fully understands an experiment to tell what he did, how he did it, and what his results show. A student should not hesitate to admit that any given experiment was a failure, or that part of his results or tracings are wrong. Such errors are frequent and will be understood at once by the instructor, and it is exceedingly valuable to the student to be able to LABORATORY DIRECTIONS 51 recognize his own failures and if possible to determine the cause of the failure. And it is of even greater importance to the student to be able to recognize and to show what re- sults he should have obtained in an experiment which has apparently failed. Not only the student, but especially the instructor, should constantly be on the watch for atyp- ical or unexpected results. Such chance observations have often furnished the basis for valuable discoveries. Blue print copies of the best original tracings {chosen hy the instructor) should be made in the department, usually by the technician, and should be furnished to the student at a price which is just sufficient to cover the cost of the blue print paper. (For directions for making blue prints, see chapter on photography, page 510.) It is important that the permanent notes for each ex- periment be written up as soon as possible after the ex- periment is performed. The records or tracings should be labeled in full and great care should be used to make them as neat and accurate as possible. No more drum space than is absolutely necessary should be used in making each tracing. The drum paper should always be smoked good and Mack. This is important for blue printing and for publication if the instructor or anyone else should care to have any tracing reproduced. It is also necessary for mak- ing lantern slides. (See chapter on photography, page 500.) Each group of students will be assigned to a table on which to work. If a sufficient nimiber of tables and the floor space are available, it is advisable for each group to have two tables, one for the experiment and the other to be used as a side table for arranging apparatus, etc. ^'\'Tien frogs or turtles are used then the two sub-groups (of two or three) may each have a table. If only one table is avail- able, then for frog or turtle work the two sub-groups should w^ork one at each end of the table. It is preferable that the drawers or lockers for the permanent apparatus be secured 52 EXPERIMENTAL PHARMACOLOGY by padlocks and that the students themselves furnish their OA\ai locks. This relieves the instructor of much unneces- sary annoyance. Special arrangements will be made for individual experi- ments or for those requiring apparatus which can not be Fig. 45. — Large bottle for holding stock salt solution. Normal tap water saline (6 Or 7 grams of NaCl to the liter) is suitable for most forms of frog or turtle work. Locke's solution contains:— NaCl, 0.92%; KCl, 0.042%; CaCU, 0.024% (crystals); NaHCOs, 0.015%; Dextrose, 0.1%. Ringer's solution contains:— NaCl, 0.6%; KCl, 0.0075%; CaCU, 0.01% (dried); NaHCOa, 0.1%. Tyrode's solution contains: — NaCl, 0.8%; KCl, 0.02%; CaCla, 0.02% (crystals); NaHCOs, 0.1%; MgCls, 0.01%; NasHPOi, 0.005%; glucose, 0.1%. Dissolve the NaHCOs before adding the CaCl2 in each case. distributed to the class. Much variation will be found in this respect in various schools. Many pieces of apparatus must be made up to fit the experiment or the facilities of the laboratory. (See chapter on shop work, page 470.) ETHER ANESTHESIA 06 A salt solution (Locke, Ringer, Tyrode, etc.) will be placed in a large supply bottle in the laboratory. (Fig. 45.) Sodinm citrate solution for blood pressure work will be supplied by the technician as needed. Unnecessary ivastage ivill he charged at cost. Specific detailed directions are given in the text for the performance of each experiment, but both students and instructors should be constantly on the watch for oppor- tunities to improve the methods and technic given or to introduce new and better experiments. The writer believes this to be the best test of the vitality, spirit, and progress of any course and he never teaches the same set of experi- ments tmce, but, on the contrary, he is constantly trying to improve or drop the old experiments and to add newer and better ones. This is even more true for apparatus, and the writer sincerely hopes that all students and teachers into whose hands this book may come will gladly contribute all that they can toward devising better, simpler, and cheaper apj)aratus. More experiments are given in this book than the class will probably be able to perform. The instructor will se- lect those best suited for the class and for the facilities of the labor atory. Experiments entirely different from those in the text may be substituted at any time. Not more than fifteen minutes should be occupied in checking apparatus. Immediately thereafter proceed as follows : EXPERIMENT I. Ether. (Action on the Central Nervous System. — Cere- brum.) 1. Under an inverted battery jar (Fig. 31) place a full grown normal frog. Take a small piece of absorbent cot- ton and pour a few cubic centimeters of ether on it. Raise the edge of the battery jar a little and slip the cotton under 54 EXPEEIMElvrTAL PHARMACOLOGY the jar. The ether vapor will fill the jar and the frog will presently begin to show symptoms from the action of the drug. Watch the animal closely. Are there pupillary, changes? Can you distinguish such stages as that of im- perfect consciousness, excitement, and anesthesia in the symptoms exhibited by the frog! Touch the animal from time to time and when all the reflexes have disappeared, remove it from the jar and quickly fasten it down to a frog board (Fig. 46) with clips, in the position shown in Fig. 47. Do not injure the animal hy unnecessary pres- sure. Place a small piece of cotton over the frog's nose and mouth and pour a few drops of ether on the cotton. Fig. 46. — Frog board and clip (Harvard). (See chapter on shop work.) With small scissors quickly make a median longitudinal incision in the skin above the brain. With the sharp point of a scalpel, held in the same manner as one holds a pen in writing, make a series of short shallow cuts in the skull directly in the median line over the cerebrum (Figs. 47 and 48). When an opening has been made through the skull, the sharp point of a small pair of scissors may be care- fully inserted and the opening thus cut larger. Be careful not to injure the brain. Check hemorrhages with small plugs of cotton. Expose both lobes of the cerebrum and then with the point of the scalpel carefully remove from behind forwards the entire cerebrum. Check hemorrhages with cotton plugs for a while, but do not compress the optic Cvfdneou5 branch of femorsldrt. M. 6/ufaeus M. Rectus interior M. V^isfus exfernus Sciafic 'arfery____A M. Triceps femoris ^^ M. Biceps Art Peroncci Art. Surd/ is Art cut (jenu /H inf. M. Peroneus n. Jib I alls anficus Art. waiieoldris lateralis Art ma/leo/dris medid/ij Art Tardea. fl. Adductor ma^nu^ N. Tibialis * A'. Peroneus 'r N. 3uralij ///) N.Cut cruris M -^ Branch of Tibial nerve to Oastroc- nemius muscle Fig. 47. — Dissection of a frog showing position of the brain, sciatic nerve and arteries and muscles of the hind limb. ACTION OF CHLOROFORM 55 lobes. Remove the cotton plugs and sew the skin together over the skull with a needle and thread, tie a thread (not tightly) around the left hind foot and place the animal on moist cotton in a casserole (Fig. 25) to recover. The action of ether is largely manifested on the cerebrum, especially in higher animals. When the animal recovers, — 0/ factory nerve -Olfactory lobe Cerebrum .Pineal body Jhahmencephdilon - Optic lobe --Cerebellum --Fourth ventricle -Medulla oblongata Long, fissure of ^9^^ vent Fig. 48. — Frog's brain. carefully compare its spontaneous and reflex actions Avith those of a frog which is just being anesthetized and also with the condition of the frog after the anesthesia is com- plete. Chloroform. (Action on the Central Nervous System. — ^ Optic Lobes.) 2. In the same manner as in the above experiment, anes- thetize a frog with a feiv drops of chloroform. Expose the 56 EXPERIMENTAL PHARMACOLOGY rigJit optic lobe and remove it. Be careful to avoid injuring- the thalamencephalon or cerebellum. Do not use too much chloroform. It Avill produce a profound anesthesia and the animal may not survive. Tie a thread (not tightly) around the rigJit fore leg and place the frog on moist cotton in a covered battery jar to recover. A fcAV hours later (or next Position of foramen magnum in,or sharp pointed probe Fig. 49. — Method of pithing a frog. A towel is sometimes wrapped around the animal to facilitate holding it. day) carefully observe the actions of the animal and com- pare these Avith those of the frog mth the cerebrum re- moved. How do these symx)toms differ from those exhib- ited by a frog which is just being anesthetized? Theoret- ically Avhat symptoms should be shoAvn by a frog which was injected with a drug that Avould depress the cerebrum alone! Or the optic lobes alone! Place both frogs in the water and observe their movements. It will be instructive if another frog can be operated on and the left optic lobe removed. ETHER; ETHYL CHLORIDE 57 What relation do the optic lobes of the frog bear to the cere- bellum of mammals? 3. Learn the technic of pithing a frog if yon have not al- ready done so. (See Fig. 49.) Ether, Ethyl Chloride, Chloroform, Ethyl Bromide. (Irritability and Conductivity of Nerve.) 4. (a) After pithing place a frog face downward on the frog board and dissect out the sciatic nerve from its origin i-7b muscle lever ^ To 'Secondary coil Fig. 50. — Harvard moist chamber. at the spinal cord down to the knee. Avoid injuring the nerve. Tie a thread to the nerve and then dissect the gas- trocnemius muscle (Figs. 47 and 60) loose from the bones of the leg. Cut the tendo Achillis long and then divide the 58 EXPERIMENTAL PHARMACOLOGY femur and thigh muscles, but leave the sciatic nerve intact and attached to the gastrocnemius muscle. Cut the tibia and fibula just below the knee and free the gastrocnemius from the remaining tissues of the leg. Fig. 51. — Harvard muscle lever. The cut end of the femur should now be fastened in the clamp of a moist chamber (Fig. 50) and a pin hook is passed through the tendo Achillis as illustrated. The thread Fig. 52. — Harvard gas chamber. passes down to a muscle lever (Fig. 51) which writes on a smoked drum. A gas chamber (Fig. 52) held in a burette clamp (Fig. 30) is placed in position near the muscle (to the ETHER, ETHYL CHLORIDE 59 right in the illustration), and by help of the thread the sciatic nerve is drawn through the holes in the gas chamber and across the two needle electrodes which are connected to an induction coil arranged for single shocks. (See Fig. 1.) By means of a rubber tube, one of the side tubes of an ether bottle is now connected with one of the tubes leading into the gas chamber. The boot electrodes (which have been Fig. 53. — Ether bottles showing method of administering air and ether (chloroform) to ati animal with the chest open, or for passing ether (chloroform) vapor through the gas chamber. soaked in salt solution and now have been filled with zinc sulphate solution) may be iDlaced just to the right of the gas chamber and the end of the sciatic nerve is laid across the tips of the boots. Keep the nerve and muscle moist with normal salt solution. The boot electrodes are also arranged so that single shocks may be sent through them when de- 60 EXPEKIMENTAL PHARMACOLOGY sired. The drum should turn at a moderate speed. Some ether is now placed in the ether bottle and by means of a hand bellows a current of air and ether vapor can be passed through the gas chamber (Figs. 52 and 53). Just before the ether is applied several contractions of the muscle should be recorded to serve as normal controls. These controls should be obtained both from the needle and from the boot Fig. 54. — Three forms of containers for ethyl chloride. The Gebauer container is preferred. electrodes. These records should be carefully preserved and compared with those obtained later. When the normals have been secured then pass a small amount of ether vapor through the chamber and then again stimulate the nerve with the needle electrodes. What action has the ether had on the irritability of the nerve? Stimulate with the boot electrodes. Has the conductivity of the nerve been af- fected! Is this a fair test? ETHYL CHLORIDE, CHLOROFORM, ETHYL BROMIDE 61 (b) Blow out the ether vapor with pure air and repeat the stimulations. Does the nerve return to normal? (c) With a Gebauer or Kelene tube (Fig. 54) spray a little ethyl chloride through the gas chamber. Do not freeze the nerve. Quickly repeat the stimulations and note the effects on the nerve. What do you observe? (d) Blow out the ethyl chloride from the gas chamber and obtain new "normal" contractions of the muscle. If ii!ill!!!l|i!llliil>?^ Fig. 55. — Method of smoking drums (in a hood). Benzol is placed in the one pint milk bottle. the nerve is dead a new preparation should be made. Place a few drops of chloroform in the ether bottle and blow the vapor of this through the gas chamber. Again stimulate the nerve with the needle and with the boot electrodes. What do you observe? What can you say as to the relative action of ether, ethyl chloride, and chloroform on isolated nerve trunks? Ethyl bromide may also be tried similarly. Before taking down the apparatus stimulate the muscle itself directly a few times to determine its condition. This is easily done if a very fine copper wire instead of a thread 62 EXPEEIMEjSJ"TAL phaemacology Veislleflfack Fig. 56.— Automatic shellacing pan and drying rack for drum records. Varnish is made by dissolving the best granular white shellac m alcohol. A large excess o* the shellac should be present, and solution is allowed to go on for a week or more (shake up thoroughly several times), at the end of which time the clear supernatant solution is decanted and placed in a well stoppered bottle to prevent evaporation of the alcohol. If this occurs small particles of the shellac precipitate out and may spoil the varnislied records by being deposited as white specks all over the black surface of the tracing. Orange shellac is somewhat more soluble than the white but not so satisfactory because of the yellowish color it gives to the records. This is very undesirable if any records are to be blue-printed, photographed or used for publication. Cheap varnishes made of gasoline and rosin, etc., are sometimes used. A high grade brass lacquer (such as Kahlbatim's metallfurniss, farblos) may often be much diluted with alcohol and thus made into an excellent varnish for records. VAENISHING AND TRIMMING RECORDS 63 Fig. 57. — \^arnishing pan (12 inches long, 7 inches wide), used for varnishing records from long paper kymographs. The record is cut apart on the drum, one person holding each end. The smoked surface is turned upward. One person steps on a stool (or short stepladder) and lifts one end of the record high in the air. The assistant dips the other end of the record into the varnish and lifts up his end of the record as the other end of the tracing is lowered. The tracing is suspended from each end like a hamrnock on the rack (shown in Fig. 56) to dry. Fig. 58. — Print and tracing trimmer. 64 EXPERIMENTAL PHARMACOLOGy is used to connect the pin hook in the tendo Achillis to the muscle lever. The secondary terminals can then be at- tached to the muscle lever and to the muscle clamp. Ethyl Chloride. (Local Anesthesia.) 5. Hold a Gebauer or Kelene tube about 10 or 12 inches from the hand and open the valve a little. A small spray of the drug mil be forced out. Why? Direct this spray -Time circuit r^ •— i — — - Tieceptacle for electrodes when not in use. 'Sprincj key The wire of ihe electrodes Should be 6 ft lonq ana lamp-cord made of yery small sized Fig. 59. — Convenient method of arranging the inductorium, battery, key and elec- trodes to avoid tearing down the apparatus at each period. The inductorium is out of the way and always ready for use. against the back of the hand. A white frost will soon ap- pear on the skin and hairs. A few seconds after this frost begins to form stop the spray and quickly examine the sen- sibility of the skin in the area affected. To what is this action due? To A¥hat clinical use might this be applied! Can you think of other substances having a similar ac- tion? Is this action of ethyl chloride in any way similar to that of ether, ethyl chloride, or chloroform, on the irrita- bility or conductivity of nerve trunks ? What is the boiling- point of ethyl chloride ? If a local anesthetic be applied to a mixed nerve trunk will all the constituent fibers be equally affected at the same time? Fig. 60. — Dissection of a frog to show the position of the heart, vagus nerve and the muscles of the hind limb. The electrodes are in position for stimulating the vago-sympathetic trunk. It is often desirable to fasten the electrodes in this position (in a burette clamp) so that the animal may not be disturbed when the nerve is stimulated. ACTION OF ETHER OjST THE HEART 65 EXPERIMENT II. Ether. (Action on the Heart. — Dissection for the Vagus Nerve in the Frog.) 1. Pith a frog and clamp it clown to the iDoard with the "ventral side up, as slioAvn in Fig. 60. With sharp scissors split the abdominal and thoracic walls in the median line forward into the skin over the floor of the mouth. If pos- sible avoid dividing the abdominal vessels. Cut open the girdle of bones directly over the heart (which should be carefully avoided) with the scissors. Then pull the tho- racic cavity widely open by stretching out the fore legs from side to side. Reset the clamps holding these legs. Refer to Fig. 60 and identify the glossopharyngeal, hypoglossal, and brachial nerves. Near the angle of the jaw dissect down carefully with a probe and fine-pointed forceps until the lar}mgeal branch of the vagus and the vago-s^nnpathetic nerves come into sight. For the method of union between the sympathetic chain and the main trunk of the vagus nerve see Fig. 61. The S3mipathetic fibers pass forward in the thorax to the base of the skull where they turn back- wards and unite with the vagus nerve to be distributed ^\ith the vagus to the heart, lungs, etc. AYlien the vago- sympathetic nerve has been found it should be pulled out- ivard a little and the points of the electrodes slipped be- neath the nerve. With a tetanizing current of medium strength stimulate the nerve and see if the heart stops. This is to identify the nerve. Do not stimulate the nerve 'Ciny longer than is absolutely necessary, for the ]ierve end- ings are easily fatigued and may not be able to stop the heart later after your apparatus is all arranged. The heart is now freed from the pericardium and con- nected with a heart lever l^y means of a pin hook and a thread as shown in Fig. 63. The tip of the ventricle is at- lached to the pericardium by a small ligament called the 66 EXPEKIMENTAL PHARMACOLOGY freniim. Pick this up with the forceps, sever it, and at the point where it is attached to the heart stick the pin hook (which should be small) through the tip or the ventricle. Adjust the heart lever to write about one-half inch from the lower edge of the drum and see to it that the tracing N.GI0550- pharyncjeai Ganalion of Vacjus 5 ympa-thefic/cha'm Art Subclavian Spinal ■' / nerves i1 Levator gnquli scapulde Vertebral column ^^^^"■^ ^." (/Iff^r Qdskell ) Descendinq ^ ' Aorta ^ Fig. 61. — Diagrammatic dissection to show the origin and course of the sympa- thetic chain and the union of the vagus and the sympathetic fibers for the heart in the frog (Gaskell). Fig. 62. — Heart lever. The rod is made of 3/16 inch round brass rod into the end of which a small hole is drilled. A small block of wood fiber or hard rubber is attached to the rod by a small wire nail which passes (loosely) through the wood fiber block and is then driven (tightly) into the hole in the end of the rod. The writing lever is a very thin strip split from a long (10 or 12 indies) section of a bamboo fishing pole. This lever, which is very light and limber, passes (tightly) through an oblong hole in the upper part of the wood fiber block. A paper or celluloid (used photographic film) writing point is attached by mucilage or by a cement made by dissolving a photographic film in acetone. These levers are entirely satisfactory for the hearts of frogs, turtles, for uterine strips, etc. They can be made easily and cheaply. RECORDING HEART TRACINGS 67 starts just to the right of the seam in the drum paper. The time marker can be arranged and the time recorded as the record of the heart beat is taken, or the time record may be put on after the heart tracings are finished if the speed of the drum is approximately constant. This latter procedure is advisable for the first few records. It is also advisable to use a signal magnet in the primary circuit ar- ranged in such a manner that the exact moment and the Fig. 63. — Arrangement of apparatus for recording frog heart tracings by the sus- pension method. The wires from the signal magnet are connected with the time clock. duration of the stimulation may be recorded directly be- neath the writing point of the heart lever. The heart trac- ing should have an amplitude of about one-half to one inch. The drum should have a slow or medium speed. If the Harvard drums are used it is often advisable to clamp a folded piece of paper on to the largest fan to thus fur- ther slow the speed. It may be necessar}^ to put a small weight on to the long end of the heart lever to secure the desired amplitude of movement for the tracing. bo EXPERIMEISTTAL PHARMACOLOGY When all adjustments are made start the drnm and take a ^'normal'' tracing. When about two inches of this has been recorded then stimulate the vagus nerve and get a record of the normal inhibition. It is important that the electrodes do not rest on the neck or thoracic muscles of the frog, for if such is the case these muscles will contract when the current is turned on and the frog will move thus spoiling the appearance of the tracing. Do not stop the heart longer than is necessary (2 or 3 beats). Then allow the heart to recover (the drum is kept running) from the inhibition and record another two inches of "normal" tracing. Then stimulate the vagus. This gives an oppor- tunity to secure two sets of records. Now back the drum away from the writing lever a little and turn it back to the starting point. Lower the drum Fig. 64. — Me(;licine dropper for applying solutions to the heart. so that the next round of the tracing will be about one- half inch above the first. Pull the drujn forward and start it again and when about one inch of tracing has been recorded then drop on to the heart with a medicine dropper (Fig. 64) five or six drops of a saturated solution of ether in normal salt solution (solubility=l to 9). AVhen the tracing again comes directly over the place where the vagus was stimulated in the lower tracing stimulate the vagus again and determine whether or not the drug has affected the reaction of the heart to the inhibition. Now rapidly drop more ether solution on the heart and repeat the vagus stimulation directly over the second inhibition record in the normal tracing. Keep dropping on the drug and note carefully the effect on the rate and amplitude of the heart. Observe the appearance of the auricles and ventricles. Can you determine in your tracing those portions of the rec- ord mjade by the sinus, auricular, and ventricular contrac- RECORDING HEART TRACINGS 69 tions respectively? In which direction does the lever move in systole? Take several rows of tracings, lowering the drum suf- ficiently to leave about three-eighths or one-half inch be- tween each row of tracings. The record should thus read from left to right and from bottom to top. As the ether is dropped on, the action on the systole of the heart will soon become apparent. This should progress until the heart almost stops. Then irrigate the heart mth normal salt solution a while and see if you can get it to recover. Stimulate the vagus from time to time and see if the power / Carohd Arch Ritjht Systemic-^ arch Ei(jht Pulmo ci/faneoiys arch ni^hi Auricle ^ / Truncus arteriosusS Ventricle Ttiahi Auricle '-LeftAnfXamI -Left Auricle Pulmonary Vein ' Biqht Carotid / arch Kiqht Systemic arch niotit Puiwo- cuhneous arch Right Ant Cetval Vein '^Openinq of Sinus venosus ink) the Eight Auricle ~Sinu5 venosus Fig. Posh Csvd vein -The anatomy of the frog's heart. (Modified from Wiedersheim.) of inhibition is lost. How has the drug affected the heart? Is the innervation of the organ involved in the action or is this mainly a muscular affair? Does this experiment show any action of the drug on the cardio-inhibitory center in the medulla ? AVhen the heart tracings are finished then record the time in five second intervals in two or three rounds on the drum. These time records also serve as comparison lines to determine whether or not there has been an increase or a decrease of tone in the heart muscle. What effect Avould a decrease in heart muscle tone have on the position of the record with reference to a horizontal line draA\m around the drum? 70 EXPERIMENTAL PHARMACOLOGY Chloroform. (Action on the Frog's Heart.) 2. Eepeat the above experiment on a fresh frog using a saturated solution of chloroform in normal salt solution (solubility =1 to 200). Does chloroform affect the nervous inhibiting apparatus of the heart ? What differences do you note between ether and chloroform as regards their cardiac action I 3. Familiarize yourself with the anatomy of the frog's heart (Fig. 65). How does the frog's circulatory apparatus differ from that of a mammal? Dorsal. Ventral. LH • pc l\mph hesri ., Fig. 66. — Diagrammatic representation of the lymph spaces of the frog. (Modified from Ecker.) Chloroform. (Action on Lymph Hearts.) 4. Allow a frog to sit in a good light with the lower end of the urostyle turned toward a window. On each side of the lower end of the urostyle {L.H. in Fig. QQ) note a series of feeble pulsations beneath the skin. This is caused by the beating of the posterior pair of lymph hearts. (The anterior pair of lymph hearts are located, one heart on each side, between the transverse processes of the third ACTION OF ETHER ON THE HEART 71 and fourth vertebi'ce. Their heats cannot he ohserved from the exterior.) Count the rate of lymph heart beats and also the rate of the blood heart beats. (These can be seen beneath the skin of the chest.) If the frog breathes also count the rate of respiration. (How does a frog breathe?) Now place the frog under a battery jar and deeply anes- thetize it with chloroform. Kemove the animal and again count the rate of beats of the heart, of the posterior lymph hearts (do these beat synchronously 1 ) , and the rate of respiration. AVhat conclusions can you drawl Are these results due to a central or a peripheral action of the chloro- form! (How is the beating of the lymph -hearts controlled? How is this mechanism j)rovided for in the mammal?) Al- low the frog to recover and observe its symptoms. How long before the frog becomes normal again? EXPERIMENT III. Turtle: Vag-us Dissection. (Action of Ether on the Heart.) 1. Pick up a turtle and draw its head forward out of the shell. This may be done with a wire having a short sharp hook on one end. The hook is passed between the carapace and plastron and hooked into the anterior angle of the lower jaw below. Draw out the head and seize it between the first and second fingers of the left hand. Clasp the hand around the turtle's neck and pith it with a sharp probe or hat pin in the same way that the frog is' pithed. It is advisable to pith the cord also by pushing a soft brass or iron wire down the spinal canal. The wire is intro- duced through the same opening by which the animal's brain was destroyed. Catch the turtle's lower jaw in the hook of a turtle board (Fig. 28) in the manner shown in Fig. 67. Pull the hind legs outward and backward firmly and forcibly and fasten them to the board. This may be done with strings (hea^^'') 72 EXPERIMEiSTTAL PHARMACOLOGY as shown in Fig. 67, but it can be done quicker and per- haps better by long sharp iron tacks which are driven through the feet and into the turtle board with a hammer. Fig. 67. — Arrangement of apparatus for recording turtle heart tracings by the sus- pension method. Note that only a small square opening is made in the plastron over the heart. It is very important that the animal he fully stretched out so that it cannot move reflexly and spoil the tracings later. Next pull out laterally the fore limbs and fasten them down firmly. EXPOSING THE TURTLE S HEART 73 Now by means of a liand bandage saw (Fig. 104), or with a circular saw on a small motor (Fig. 68), cut out a square opening in the plastron over the heart as shown in Fig. 67. With a scalpel handle pry up the square piece of plastron and then carefully strip loose the tissues below the square so as to avoid hemorrhage. There should be practically no bleeding. With scissors cut away the peri- cardium and expose the heart. Familiarize yourself with the anatomy of the turtle's heart (Fig. 69). In the side of the neck make a longitudinal incision and Circular ^P'1^^^ . _53jy « extension Fig. 68. — Method of sawing ^ut a square in the plastron of a turtle by means of a circular saw (3 inches in diameter) attached to a small (1/10 horse power motor). expose the carotid artery, the vagus nerve, and the sym- pathetic nerve (Fig. 70). To identify the vagus nerve place a thread around it loosely, lift up the thread, and with a moderately strong tetanizing current stimulate the nerve. Does the heart stop beating! If not, strengthen the cur- rent. The heart normally should entirely cease to beat when the vagus nerve is stimulated with a sufficiently strong- current. Arrange the turtle and apparatus to record a heart trac- ing as shown in Fig. 67. It may be desirable to use the signal magnet in the primary current for the induction coil 74 experimejsttal pharmacology and thus let the signal magnet record the moment and du- ration of stimulation rather than the time. After the heart records have been secured then the time tracing (in five second, etc., intervals) can be put on the drum. The electrodes should be adjusted under the vagus nerve in such a way that they need not be disturbed or moved in any way when one desires to stimulate the nerve. Keep the nerve moist with normal salt solution. The record should be made in such a manner that it will read from left to right and from bottom to top. The amplitude of the beats should be about one inch. The drum should turn at a moderately slow speed. When all adjustments of the apparatus are completed record about one or two inches of the normal tracing and then stimulate the vagus nerve. The right nerve usually is more effective in stopping the heart than is the left. Allow the heart to recover (the drum should be kept going all the time) and when about one or two inches more of normal record have been ob- tained, stimulate the vagus (or the opposite vagus) again and thus get two sets of records. If there are three stu- dents in the group it is often advisable to thus make three sets of records so that each student can have one. The cardiac inhibitory poAvers of the vagi in the turtle are not nearly so easily exhausted by electrical stimulation as are those of the frog. When enough normal tracings have been secured lower the drum so that about one-half inch will be left between the first round of the record and the second and start over from the beginning (left hand side) of the record again. When the second record reaches a point about one inch to the left of the place where the vagus nerve was stimu- lated in the first round then rapidly drop ten drops of a solution of ether in salt solution on the heart as was done with the frog's heart in Experiment II (1). A¥hen the record comes directly over the place where the vagus nerve was stimulated in the first round of the tracing stim- Carotid art 1 im Cdrofid drt. Subd&v. ^rt- ^^^ Pulmo. ^rt^^^^^ ^^^^^F^ i'Sup. Subcldvisn art Venae csvee. ^^^ Pulmonary drt Pulmo.Q^ ^ /' ] vein \^^^''^{ f m P^" ^^^Pu/nT^B[^ nt Auricle -^M^^^_^ ■^If^M Lft Auricle Inf. Ke/)a cai/a ^^ L ventricle m /?/: Aortic srch — ^ V i Coeliac arteries 1 -Dorsal Aort^ ^,/^^c^ Fig. 69. — Diagrammatic representation of the turtle's heart. (Modilied from Nuhn.) INNERVATIOISr OF THE TURTLE S HEART iO Testudo qraecd Specimen A Fig. 70. — Schematic representation of the vagus and sympathetic nerves in a turtle (testudo graeca). (Modified from Gaskell.) \'ariations in the arrangement of the sympathetic fibers were frequently found by Gaskell. (The writer has seen no instance in which the arrangement and connections of the sympathetic fibers existed as shown in this illustration, but the general plan of distribution appears to be approximately the same in all specimens.) 76 EXPERIMENTAL PHARMACOLOGY ulate the same nerve again with the same strength of cur- rent and determine whether or not the nervous inhibitory mechanism has been affected by the ether. Is the ampli- tude, the rate, or the tone of the heart affected? If the tone of the muscle is loAvered how will this affect the trac- ing? (After the records are all obtained, draw two or three parallel lines around the drum by rotating it against the writing point of a stationary signal magnet or tam- bour. By comparing the general rise or fall of a whole round of heart beats with this constant line any change in muscular tone will be observed at once.) Apply ether solution to the heart rapidl}^ ond at the proper position stimulate the vagus nerve. Take several rounds of the tracings (lowering the drum a suitable dis- tance between each two rounds) and observe the continued action of the drug on the heart. Does the vagus nerve be- come more or less effective in stopping the heart? How do you explain this action? The drum may be stopped for a while at the end of each round if the changes in the heart come on very slowly. When the heart has almost stopped, then proceed to rap- idly wash off the ether with warm normal salt solution. See if you can get the heart to recover. How do you ex- plain any peculiar rises and falls in the general contour of your tracings? How can you prevent these in later rec- ords? Were you warned about this before? Chloroform. (Action on the Turtle's Heart.) 2. Repeat the above experiment on a fresh turtle using a saturated solution of chloroform in tap water saline. Does the chloroform affect the nervous inhibitory apparatus of the heart? What difference do you note between ether and chloroform as regards their cardiac action? ETHER, CHLOROFORM, ETHYL BROMIDE a EXPERIMENT IV. Ether, Chloroform, Ethyl Bromide. (Dog: Respiration, Blood-pressure, Cervical Vagi, and Sympathetics.) 1. (a) Read the following directions over very carefully at least once before starting the experiment. It is exceed- ingly important that you learn the proper technic for the following procedures correctly at the start. Arrange the table for the experiment as shown in Eig. 117. Anesthetization of the Animal. — (a) Treat the dog- gently and kindly and do not irritate or frighten it. Two Fia 71. — Method of etherizing a dog. The animal sliould not be frightened or hurt. (For description see text.) (or three) students should apply the anesthetic. The ani- mal is caught by the head and legs and gently placed on its left side {ivhy left?). If the animal is vicious it should be muzzled at the start. The anesthetizer seizes the head gently but firmly and lays it down on a towel which has already been placed flat on the floor (Fig. 71). The head is held by the right hand and the ends of the towel are 78 EXPERIMENTAL PHARMACOLOGY brought up separately and wrapped about the head. The right hand then carefully seizes the towel and holds it tightly around the neck of the dog. The towel thus forms a kind of sack or tube around the dog's head. The distal end of this sack is now seized with the anesthetizer's left hand and twisted around two or three times and then placed flat on the floor where it is held dowu firmly with the anes- thetizer's left foot. Both the anesthetizer and the assist- ant should stand behind the dog. (Why?) The assistant reaches forward over the animal and holds both fore feet in the left hand and the hind feet in the right hand. To prevent the dog from getting up the anesthetizer holds its head firmly down to the floor with his right hand and the assistant places one (or both) knees on its body. If the dog is muzzled, two students can thus control almost any dog with but little trouble. (In practice one seldom muz- zles the dog.) Caution. — There should always be kept in plain view and in easy reach in the laboratory a bottle of carbolic acid solution and a bottle of alcohol. These should be kept together and a toothpick with a little cotton wrapped around one end should be stuck in the cork of the carbolic acid bottle. One never knows when a student may be bitten by a dog, and as all dogs or cats are subject to rabies, any wound made by the animal's teeth or claws should be cauterized with carbolic acid immediately. This is done by wetting the cotton on the toothpick with the acid and applying it to the wound. In a few seconds the acid will penetrate the tissues as deeply as the virus has probably gone and then the acid should be carefully washed off with the alco- hol. This dissolves out the acid and removes it. The acid may cause the tissues to take on a whitish, cooked appearance, but the alcohol often removes this entirely. Do not Mil the anivial if the wound appears at all dangerous. Save it carefully for diagnostic purposes. Consult a first-class bacteriologist or the city health department. As shown in Fig. 71 the anesthetizer now drops some ether on the towel in front of the animal's nose. The dog will struggle some and should be held firmly. With suf- ficient ether the animal should be anesthetized in about two minutes. Be sure the dog gets sufficient air through the towel. Watch the respiration closely. The animal will ANESTHETIZATION OF ANIMAL 7iJ likely hold its breath at the start. The danger signal af- ter this preliminary holding of the breath is stoppage or great shalloivness of the respiration. Avoid this carefully. When the limbs become limp and drop down flaccidly when lifted and turned loose then touch the cornea gently and see if the dog winks. If not, hastily place it on a dog board on the table *(Figs. 20 and 72). The animal's head is quickly draw^i forward between the upright posts and the rod is pushed through between the teeth (just behind the long Fig. 72. — Ivaboratory table. The top of the table is 5yi feet long and 33 inches wide. The height is 35 inches. The small square stand at the head of the table is 13 inches square at the top and has a small (7 inches) round sink in the center. Gas (G), air (A) (positive or negative pressure, constant or interrupted current), hot (H W) and cold (C W) water, inductorium or battery current (B), clock current (T), and drop light circuit (Z,) are all connected with the (immovable) square stand. The piping for the water, electricity, etc., runs in the floor. One locker and one large drawer are available on each side of the table. The dog board is in position on the table. The sink, etc., should be at the end of the table toward the window. canines). A heavy twine about sixteen inches long should have been previoush^ laid across the board just back of the upright posts. When the rod is pushed in this twine is then ready to be brought up at once and tied as tightly as possible around the dog's mouth just hacJx of the rod. 80 EXPERIMENTAL PHARMACOLOGY Fig. 75. — Metronome for operating the electric time signal. Fig. 74. — L,ieb-Becker time marker made from an Ingersoll watch. Time intervals ■of 1 second, 5 seconds or 1 minute may be recorded. Obtainable from Mr. J. Becker, Terrace Avenue, Maywood, N. J. Price $5.50. (See C. C. Lieb: Jour, of Pharm. and JJxper. Therapeutics, 1917, 9, 227.) ANESTHETIZATIOISr OF AISTIMAL 81 The operator uses both hands to draw this string tight, and when the first knot is tied the assistant places his right thumb over the knot to hold it tightly while the second knot is tied. Why should this string be tied so tightly? Fig. 75. — Harvard time clock. The average student will probabh?' find out before the first experiment is finished. The toAvel is now quickly tucked down over the dog's, mouth and nose and a little ether is poured on. The most steady and reliable student in the 82 EXPEKIMENTAL PHARMACOLOGY Fig. Id. — Jaquet chronograph (records in intervals of 1/5 second and 1 second). Fig. "jj, — Two forms of time clocks. (Both made by E- Zimmermann, lycipzig and Berlin.) The large clock (Bowditch-Baltzar) marks intervals of 1, 2, 3, 4, S, 10, 15, 20, 30 and 60 seconds. ARRANGING FOR OPERATION group now takes charge of the anestlietic and henceforth directs Ms attention solely to this ivorh. Quickly slip the cords (each of which has a slip noose, Fig. 79) over the Fig. 78. — Method of fastening the animal's head to the dog board. Fig. 79. — Heavy string with slip noose ready to put around the fore limb. fore legs up to the elbows (Fig. 80). Draw these cords tightly and then wrap the ends around the screw eyes at the edge of the dog hoard (Fig. 81.) After the third or 84 EXPERIMENTAL PHARMACOLOGY fourth round draw the end of each cord in between the screw eye and the edge of the board. This will usually Fig. 80. — Method of attaching fore limbs to the dog board. Fig. 81.— Method for quickly fastening the string to the board without tieing any knots. hold tightly and saves tying any knots which should be avoided if possible. Stretch out the hind legs and tie them down as shown in Fig. 82. PRELIMINARY OPERATIONS oO (b) Insertion of Tracheal and Carotid Cannulas; Isola- tion of Vagi and External Jugular Vein. — As soon as the animal is securely fastened doA\ai, a median incision is made in the skin and fascia over the trachea as shoA\m in Fig. 83. Observe with great care the technic shown in the ilhistration and follow it carefully. Next take two aneurism Fig. -Method of fastening the hind limbs. needles and separate the mesial borders of the sternohyoid muscles as shown in Fig. 84. This brings into view the trachea (Fig. 85) with the carotid sheath containing the carotid artery and vago- sympathetic nerves on each side (posteriorly) of the wind-pipe. Next take an aneurism needle and hook it under the trachea as shown in Fig. 86. With the largest forceps pick up by one end the hea^^^ twine to tie in the tracheal cannula. While holding this in the forceps lift up the trachea with the aneurism needle and push the forceps (holding the t^^^.ne) through the EXPERIMENTAL PHAEMACOLOGY fascia back of the trachea. About half the length of the forceps is pushed through below the trachea and the for- ceps are thus left in place to hold up the trachea. The end of the twine is taken out of the forceps and the twine is drawn through a little over half its length (Fig. 87). The Lefi hand of l.^fih6nd of /Issisfani: Knife in 'Ki.H^nd of Opr Incist'on -thru skin s/ Tascia fo Muscle. -Method of incising the skin over the trachea. twine is then tied loosely and with scissors the trachea is cut crossivise about three-fourths in two (Fig. 87). With large sharp-pointed forceps the operator (right hand) now holds open the cut portion of the trachea while the assist- ant (right hand) pushes in the tracheal cannula (Fig. 88). This is at once tied in and connected with the ether bottle PRELIMINARY OPERATIONS 87 rig. 84. — Separation of the borders of the sternohyoid muscles with two aneurism needles. Cefro^id. sheaf h Conf-aininq ygao- gfheiic ner^e 5ympgrh&ric nen^e ^ Caroh'd earfery M. Sferno-hyoideus ^*>V^- Pig. 85. — The trachea is exposed and the carotid sheath is seen just to the postero- lateral border of the windpipe. EXPERIMENTAL PHARMACOLOGY Fig. 86. — An aneurism needle is used to lift up the trachea while the forceps (holding the end of a heavy string) are passed beneath the trachea. Cu(i Trachea 3/^ fhru, cross- wise, i>e/*ree/? n'nqs. Shincj loosely tied onfrache.. B'^ig. 87. — The string is tied loosely and the forceps are left in position to hold up the trachea which is cut crosswise about three-fourths in two with the scissors. PKELIMINARY OPERATIONS 89 Fig. 88. — Insertion of the tracheal cannula. M Caroiid arkr\j d- f,(7) V^fus tfer/e- y\ \^^ bluni poirrhed C=^^^^ probe. Doni use hni^ Fig. 89. — Lifting up the right carotid sheath on an aneurism needle. A blunt probe is then vised to separate the vago-sympathetic trunk from the artery. 90 EXPBKIMEE^TAL PHAEMACOLOGY Loose liaahre, TIace on wiirh forceps^ NOT v/ifh fin(^e. ~^ '~~ Liaai'ure on Vaqo sympafhefic nerve loose Licj. arouvdarhr^- Tisce ov yriih forceps, W/A...... /YOT ty/H f infers ^ ^^^ Fig. 90. — Ligation of the carotid (in two places) and vago-sympathetic nerve. /Issisfj/ii- Fig. 91. — Opening the carotid artery. (The incision should be made nearer to the upper ligature and the scissors should point more toward the heart than the picture indicates.) PRELIMINARY OPERATIONS 91 Fig. 92. — Insertion of the arterial cannula. The cannula and tubes contain no solution; this is run in later after the cannula is firmly tied into the artery. Pos/hon of ExtJuaulsr V. Fig. 93. — The cannula is tied into the artery. The right external jugular vein is dissected out by pulling the skin outward while the muscles and fascia are scraped back inward with the probe. The vein lies in the fascia as indicated. 92 EXPEKIMENTAL PHARMACOLOGY and the screw clamp on the straight end of the cannula is adjusted to make the dog breathe just enough ether to keep the anesthesia constant (Fig. 89). The forceps beneath the trachea are withdrawn and the aneurism needle is hooked under the right carotid sheath which is lifted up out of the wound (Fig. 89). With a hlunt-pointed probe the sheath is opened and the carotid artery and vago-sym- pathetic trunk are separated. A ligature is placed under the nerve and tied loosely. A bull-dog clamp is placed on the ends of this ligature (Fig. 90) which is now dropped down beside the neck. Similarly with forceps two more ligatures are placed on the carotid artery and tied loosely (Fig. 90). It is extremely important that the student learn to do these operations ivitJi his dissecting instruments — not ivitJi his fingers except to tie knots, etc. Many stu- dents bring with them from their anatomy courses an ab- surd notion that they should do most of their dissections with their fingers. Learn to use your dissecting instru- ments. That is the only royal road to first-class operative success. Place a bull-dog clamp (serrefin) on the carotid low down in the neck and tie tightly the upper ligature. The lower ligature lies close to. the bull-dog (Fig. 91). Place the scissors ready to cut the artery about half in two at a point just heloiv the upper ligature. (Why here?) The assistant holds a piece of cotton just over the end of the scissors to catch any blood that may fly out of the seg- ment of artery as the operator cuts with the scissors (Fig. 91). With the large sharp-pointed forceps the operator now holds open the artery while the assistant pushes in the arterial cannula (Fig. 92) which is already connected with the manometer. The washout tube and clip are also on the side tube of the cannula. There is no fluid in the cannula or tube connecting it to the manometer. This fluid is rmi in later ivhen the operation at the neck is complete. If the tip of the cannula does not enter the artery readily the cannula should be dipped into a beaker of water and then inserted into the artery. This is the usual method to PRELIMIlSrARY OPERATIONS 93 get a cannula into a vessel. The cannula is now tied in tlie artery (Fig. 93). (If desired for injections the right external jugular vein may also be dissected out just be- neath the skin and fascia of the neck — Fig. 93.) In a similar manner isolate and ligate loosely the left vagus nerve. (c) Insertion of Femoral Injecting Cannula; Dissection of Femoral Artery and Vein and Saphenous Nerve. — Ob- masm^ Fig. 94. — Burette, tubing, clips and cannula arranged for connecting with a vein for injection of drugs. serve with great care the arrangement of the apparatus shown in Fig. 94. Solutions to be injected into the veins are placed in the burette. The cannula is tied in the vein, a bull-dog clamp being always left on the vein just prox- imal to the cannula. When injections are made the bull- dog is loosened and the dose is measured by opening cau- tiously the clip on the tube leading from the burette. As soon as the drug is injected the spring clip is closed and the bull-dog is replaced on the vein. This is a double check 94 EXPERIMENTAL PHARMACOLOGY for safety to prevent the unintentional injection of drugs. This cannula is exactly similar to the one in the carotid artery. Drug solutions in the burette can be changed quickly by running the solution out at the side (wash-out) tube. The burette is then rinsed with water and the sec- ond drug is poured into the burette. To get the air out of the tubing the two clips are opened a little and some of the drug solution is washed out at the side tube. The solution is caught in a beaker and returned to the burette. When the burette is to be inserted at first some normal salt solution should be placed in the burette and a little of it run through the cannula. This wets the inside of the cannula (and tubes) and prevents air bubbles from stick- ing inside the cannula later on when the drug is poured in. Just as the cannula is inserted into the vein some of this salt solution is run out and the end of the vein next to the cannula is thus filled with solution and the air is driven out. If air is left in the tubes, cannula or vein, then the animal may die of air embolism when the drug is injected. Ahvays carry out this teclmic ivlien putting an injecting cannula into a vein. To dissect out the right femoral vein consult Fig. 199. Place the tip of the finger in the inguinal region just at the lower outer edge of the abdomen. The pulsations of the femoral artery will be felt just beneath the skin. With the large forceps pick up a narrow fold of the skin directly over the pulsations and cut this fold away ivit'li the scissors as shown in the illustration. Do not use a scalpel. When the skin and fascia are thus cut away an opening resem- bling that shown in Fig. 95 will be made. With a blunt- pointed probe dissect away the fascia between the sartorius and adductor muscles. The vessels will be seen in the floor of this triangular space as shown in Fig. 96. Use only the prohe or hlunt-pointed forceps for the dissection. When about one-half inch of the vein has been freed from the fascia slip an aneurism needle under the vessel and lift PRELIMINARY OPERATIONS 95 it up. Free it from fascia for a distance of three-quarters or one inch and then tuith the forceps place two ligatures loosely under it. Tie these loosely and place a bull-dog on the vessel close up to the proximal end of the freed space. The distal ligature is now .tied tightly, the vessel is Cephalad Fig. 95. — A blunt probe is used to dissect the fascia away from the femoral artery and vein. lifted on the aneurism needle, and with the scissors a cut about three-fourths across the vessel is made close to the distal tied ligature. If the segment of the vessel was full of blood the assistant should hold a piece of cotton over Cephalad Fig. 96. — Position and relations of the vein, artery and nerve. the points of the scissors as the cut is made. The opera- tor now holds the vessel open {supporting it on the hook of the aneurism needle) with the large sharp-pointed for- ceps while the assistant inserts the cannula, running out a 96 EXPERIMENTAL PHARMACOLOGY little salt solution at the same time. The camiula is now tied in and the remaining salt solution is run out through the side tube. The relations of the vein, artery, and nerve are shown in Fig. 96. You ivill need to Txfiow these rela- tions ivell for future operations. Now pour into the empty burette about fifteen cubic cen- timeters of adrenaline solution 1-10,000 (Parke, Davis and Co., adrenaline chloride; or synthetic levorotatory adren- aline, Farbwerke-Hoechst Company, New York. The former is advisable). Wash out a little of the solution to get all air out of the tubes. Save the solution washed out and return it to the burette. (d) Recording Blood-pressure. — Bring the writing point of the manometer (mercury) to the smoked surface of the drum. It is exceedingly desirable for the manometer to carry a signal magnet which marks the base line, or line of zero pressure, and at the same time marks the time intervals as recorded from a master clock, Jaquet chrono- graph, metronome, or other time recording device. The construction of the manometer is shown in Fig. 6. This illustration also shows the method of connecting the man- ometer to the pressure bottle. The best anti-coagulating so- lution to be placed in the pressure bottle for filling the tubes, right limb of the manometer and the cannula, is a solution of sodium citrate (5 to 10 per cent). (Several other salts, Na2S04, NaHCOo, MgS04, etc., in varying strengths, are sometimes used.) The signal magnet point should mark about three-fourths of an inch to the left of the manometer pointer. This avoids breaks in the time record in the early part of the tracings. Hold a battery jar under the wash-out tube and open the corresponding clip. Now open the clip at the top of the manometer. The sodium citrate solution will quickly run down and fill the tubes, manometer, and cannula. All air will be washed out. Close the clip on the side tube while the upper clip remains open. In this manner run in citrate solution sufficient to raise the PRELIMIISTARY OPERATIONS 97 pressure in the manometer until the manometer pointer writes about one and one-half inches ahove the base line. Do not raise this iwessure too high. Why? See that both clips are tightly closed and then remove the bull-dog from the artery. The pressure in the manometer should rise sufficiently to lift the writing point about three-fourths or one inch higher than it was. The pressure bottle should be suspended from a pulley at the ceiling and the bottle should be kept about four or five feet above the table. Some workers put the pressure bottle on the table and use compressed air to force the fluid out. The writer advises that this method be avoided at least in student work, for all the space on the table top is needed for other apparatus. Furthermore, it sometimes happens that students do not projDerly close the clip at the top of the manometer and then the dog may soon bleed to death by forcing blood out into the tubes and pressure bottle, Avhile at the same time citrate solution rather quickly passes doA\m into the carotid artery. This solution is very poisonous and soon kills the heart. If the bottle is sus- pended above the table the instructor can quickly see if any blood is backing up into the bottle. In addition it is much easier for the instructor to see at a glance just how much citrate solution each group of students has ahead for the experiment. (e) Recording Respiration. — Xear the middle of the thorax pass the long string of the stethograph drum under the dog (use the hook of an aneurism needle to reach un- der the animal) and bring it up on the opposite side. Ad- just the two strings of the stethograph with a moderate tension and clamp them together with a hemostat or bull- dog. If too little movement is thus secured for the stetho- graph membranes place fairly large wads of cotton under the strings on either side of the chest. Now connect a rubber tube (which carries near the middle a T-tube with yy EXPERIMENTAL PHARMACOLOGY a side tube and clip) to the stethograph drum and attach the other end of the tube to a tambour which writes on the drum. The respiratory record should be adjusted to give an amplitude of about one inch and should be re- corded heloiv the hlood-pressure and about one-half inch above the base line (recorded by the time signal magnet on the manometer or by a signal magnet placed separately on a stand). (f) Adjustment of Writing Points. — On the drum now adjust the writing point of the manometer in such a posi- tion that if the blood-pressure falls very low then the writ- ing point will just barely pass do\\Ti to the right of the re- spiratory tambour. This is an important point in technic and must ahvays be foreseen and provided for especially if three or four tracings are being recorded at the same time. The anesthetist should have maintained an even anesthesia throughout these procedures. His guide is the depth and regularity of the respiration. After the blood- pressure record is started then it also furnishes valuable information regarding the depth of the anesthesia. The respiration, hoAvever, is the most important and should be watched closest. While the anesthetist is personally re- sponsible for the life of the animal yet it is the duty of each student in the group to keep as careful and constant a watch on the animal as possible. Each animal lost care- lessly should be carefully checked up against the anes- thetist and his group, and should be duly considered in making out the respective grades at the end of the course. There are certain objections to this method of record- ing the respiration, but it is probably the best one for student use, (g) Other Methods of Recording Respiration. — Some workers record respiration by connecting the tambour to the side tube of the tracheal cannula. If ether is given through a bottle or if artificial respiration is suddenly PRELIMIIsrAllY OPERATIONS 99 needed this method is of but little use. If the animal be kept under the influence of a hypnotic such as chloretone, then it may be of some use. It is best, however, that the method be avoided, at least by students. Cushny has de- vised a special apparatus for recording respiration where greater accuracy is required. The apparatus consists of a long narrow box with one-half or more of the ends (up- per part) removed. The box can be turned bottom up- wards over the animal as it lies on the operating table. A very thin flexible rubber membrane is stretched loosely in- side the box, being attached (air tight) to the sides and ends. The bottom of the box (now turned upward) thus forms a closed cavity over the entire chest and abdomen of the animal (rabbit). When the animal inspires the rubber membrane mil be lifted up and the air in the ux)per part of the box will be driven out through a tube to the recording tambour. Another tube in the box carries a short rubber tube and a screw clamp. This serves as an adjustable by-pass for the excess air if the tambour is too small to record all changes (as are all tambours now on the market). A small spirometer may also be used to re- cord the respiratory movement by this method. (See also Cushny and Lieb, Journal of Pharmacology and Experi- mental Therapeutics, 1915, vi, 451.) Another method of recording respiration consists in at- taching a string to the tip of the ensiform (Xiphoid) car- tilage by means of a pin hook. The string passes over pulleys to a lever (or to two connected tambours) Avhich writes on the drum. (h) Beginning of the Records. — Take the bull-dog off the carotid artery if this has not been done before and ob- serve the blood-pressure tracing on the drum. Adjust the pointer and also the respiratory tambour if it is not al- ready making a satisfactory record. Bo not proceed ivitli the experiment until a perfectly satisfactory record is he- 100 EXPERIMENTAL PHARMACOLOGY ing obtained. Be sure the drum is wound up and set for a slow speed. Start the drum and take two inches of normal record, 2. Stimulate the right vagus nerve (the drum is kept going) witla a moderately strong tetanizing current. What are the effects on blood-pressure and respiration? How do you explam this! 3. Open the left eye and while observing the pupil closely stimulate the left vagus nerve. What do you observe? How do you explain this! Repeat this on the right side. 4. Crowd on the ether vapor by shutting off the straight end (for air) of the tracheal cannula and shaking up the ether in the bottle. The dog thus breathes a very concen- trated vapor. What effect has this on the respiration and blood-pressure! Do the heart beats become slower! Can you determine this mth a mercury manometer! Increase in the amplitude (up and doA\m) of the manometer strokes indicates a slowing of the heart. ^Vhy! A^Hiat mechanical factors are involved! Do not mistake the reflected effects of respiration on the blood-pressure for a change in the amplitude of each separate heart beat. AIIoav the animal to return to normal. Stimulate the vagi nerves. Are the)^ more or less active in affecting the heart and respiration than before! What nerves are concerned in these respira- tory effects and over Avhat paths do the impulses travel! At what points might an excess of ether affect these! 5. Give the animal a few breaths of chloroform vapor. This is best done by taking an empty ether bottle (1 pint milk bottle) and putting about two cubic centimeters of chloroform into it (Fig. 89). The cork of the ether bot- tle connected to the dog is now removed and inserted into the second bottle. The chloroform vapor mil be quickly inhaled by the animal and there will be an immediate change in the blood-pressure and respiration. Do not alloiv these changes to go too far. Remove the chloroform bottle and allow the dog to recover. Replace the ether. This may be ASPHYXIA AND RESUSCITATION 101 repeated two or three times to secure more sets of rec- ords. Now inject one-fourth cubic centimeter of adren- aline. Do you get a normal effect! Ask the instructor about the appearance of this record. You may need a larger dose. Compare the effects of ether with those of chloroform on the blood-pressure and respiration. Which do you consider safer? Why? 6. Allow the animal to recover. Then place some ethyl bromide (3 or 4 c.c.) in a second milk bottle and attach it to the tracheal cannula. Compare the action of this drug with that of ether and chloroform. Learn the odor of each of these drugs. 7. If Harvard kymographs are being used one student should see to it that at least one well smoked extra drum is always available. Allow the animal to return to a satis- factory^ condition and then close off both openings from the tracheal cannula. The animal will soon become as- phyxiated. Be sure you secure a good tracing of this. Observe carefully the changes in blood-pressure and res- piration. How do you explain these? How do the respiratory movements affect the blood-pressure? Con- tinue the asphyxia until either the heart or the respiration finally stops. What is the immediate cause of death? Now open the tracheal cannula and at once give the animal artificial respiration (the ether should be removed) either with a hand bellows, or better, by means of a special respiration machine (Fig. 360). Inject one cubic centi- meter of adrenaline solution. The lungs should be inflated about twent}^ or twenty-five times per minute. Does this affect the heart or respiratory center? Continue it for ten minutes if the animal does not recover sooner. Stop when you detect sufficient signs of recover}^ and alloAV the animal to return to normal. Now give the animal suffi- cient chloroform to stop both heart and respiration. Im- mediately apply artificial respiration and try to revive the dog as you did before. Compress the chest over the heart 102 EXPERIMENTAL PHARMACOLOGY intermittently with both hands. Watch the movements of the manometer as you compress the heart. Does this af- fect the blood-pressure? Quickly inject from the burette two cubic centimeters of adrenaline solution and continue the artificial respiration and heart massage for ten min- utes if the animal does not recover sooner. What treat- ment would you advise for threatened death under an anesthetic ? How would you apply this treatment in a mod- ern hospital? If the animal revives (it of course never comes out from under the influence of the anesthetic) then again clamp off the A^dnd pipe and allow it to die of as- phyxia. 8. If time permits make the following dissections : Open the chest by a median incision over the sternum. To do this incise the skin and fascia down to the sternum, and saw (Fig. 104) this through exactly in the median line. (See Fig. 105.) Pull open the chest from side to side and expose the lungs and heart (inside the pericardium). In- flate the lungs. Open the pericardium and expose the heart. Observe all the important structures in the chest. Cut the phrenic nerves where they lie on the pericardium. Could you make this dissection in a living animal? 9. Carefully clean up the table, manometer tubing, can- nulas, etc., and put away all your apparatus. It is im~ perative for each group to clean up its own apparatus after each experiment. The animal must be put in a garbage can or box with the others and should be burned in the furnace at the power or heating plant. The records obtained during the experiment should be labeled at once. The appearance of the record can often be greatly improved by drawing a few straight lines horizon- tally through the tracings by rotating the drum against a stationary tambour pointer before the paper is removed from the drum. (See Fig. 190.) Rough notes should be made during the experiment. The record is varnished and dried, and the permanent notes should be written up as soon as possible. ETHEK^ CHLOROFORM, ETHYL BROMIDE 103 EXPERIMENT V. Ether, Chloroform, Ethyl Bromide. (Dog: Motor Areas, Blood-Pressure, Blood, Heart.) 1. Arrange a dog as in Experiment IV, for recording blood-pressure. Put adrenaline solution in the injecting burette (in the femoral vein). Be sure the anesthesia is regular and sufficiently deep. 2. Loosen the dog's mouth and the right fore leg. Turn the head and part of the chest over toward the left so as to leave the top of the head turned well over to the right. If the instructor advises it turn the dog's head entirely Fig. 9T . — Removal of a triangular area of skin and fascia over the skull for a trephine opening. over so that the top of the skull is directed upward. In this case watch that the respiration is not hampered or that the carotid or tracheal cannulas do not become dis- turbed by compression of the carotid artery or trachea. Observe Fig. 97 carefully. Make a median longitudinal incision in the skin and fascia down to the skull as sho^^m in the illustration. With large scissors (Fig. 98) cut out a triangular piece of skin and fascia. At the place marked 104 EXPERIMENTAL PHARMACOLOGY '^C'^ in Fig. 99 a curved, line will mark the point of at- tachment of the temporal muscle [T). With a scalpel cut the edge of the muscle loose from the bone exactly in this line. Now dissect the muscle loose from the skull by cut- Fig. 98. — Six inch tinner's snips used for cutting thick skin and fascia, etc. ting the periosteum from the bone and reflecting the muscle outward from the median line. Be sure to keep the dis- section and cutting close cIoaati to the bone to avoid the Fig. 99. — A trephine opening (O) has been made in the skull {S) and the dura mater (B) beneath is exposed. The electrodes can be applied to the dura mater over the various centers in the motor area. C, line of attachment of the reflected temporal muscle {T). M, median line beneath which is the great longitudinal sinus. muscular blood vessels. Pull the reflected edge of the muscle upward with a hemostat as shown in Fig. 99. Now take a trephine instrument (Fig. 100) and at a point about EXPOSURE or MOTOR AREAS 105 one-half or three-fourths inch from the median ]ine make an opening through the skull. (It may be necessary later to enlarge this opening.) Be sure to keep far enough out from the median line to avoid the great longitudinal sinus inside the skull (S). (If this is opened accidentally quickly 100. — Trephine. remove the trephine instrument and tightly plug the open- ing with cotton to stop the hemorrhage. Then turn the animal over and perform the operation on the left side.) Remove the button of bone and the dura mater over the 106 EXPERIMEIsTTAL PHARMACOLOGY brain should be seen as shown in Fig. 99. Now allow the anesthesia to become as light as possible without letting the animal come out from under the influence of the ether too much. With the platinum electrodes (medium tetaniz- ing current) begin to stimulate the exposed dura mater at various points. Try to pick out some centers for various muscular movements. Observe Fig. 101. Make careful LoiKjifudinsI sulcus CrucidI sulcus {Fissure of 'Rolando) Center for Ihe neck muscles. penter jvr I'he exi-ensorj s- adduciorjf of fhe forelimo. center for ihe flexors s>- roiation of f/ie forelimh. -cenier for i'he nind limb. ceni-er for ike muscles innerval-ed by Me facial. Fig. 101. — Upper surface of a dog's brain. (Modified from Sisson.) note of the position of the electrodes for each of these centers and observe closely the extent and strength of the movements produced. Be sure you understand the an- atomy of the nervous paths by which these movements are originated and controlled. Now deepen the anesthesia and again stimulate. Is there any change in the response of ETHER, CHLOROFORM, ETHYL BROMIDE 107 Again lighten the anesthesia and secure the muscles? more ''normal" movements. Now give the animal a lit- the {not too much) chloroform and again stimulate. Are the movements affected in any way? How does this com- pare with ether! If the instructor advises it the action of ethyl bromide on the motor areas may be tried also. Re- place the animal in the usual position and re-adjust your apparatus. I Fig. 102. — "Straight" glass cannula. Several different sizes of these are often needed. 3. Dissect out one femoral artery (Fig. 96) and place in it (pointing toward the heart) a small straight cannula (Fig. 102). Leave a bull-dog clamp on the artery proxi- mal to the cannula. Into a test tube draw off about three or four cubic centimeters of blood from the artery, and at once pour an equal quantity of ether into the blood. Shake the two together for a few seconds and set the tube Fig. 103. — Hand bellows. aside for two or three minutes. Then observe the appear- ance of the blood. Can you detect any changes'? How do you exx)lain this? 4. Repeat this with chloroform. Do these tubes of blood clot? 5. Repeat with ethyl bromide. 6. Cardiometer. — Arrange for artificial respiration. If 103 EXPEKIMENTAL PHARMACOLOGY possible this should be done with a thoroughly reliable res- piration machine (Fig. 360). If this is not available then use a hand bellows (Fig. 103). Prepare a needle and thread and four strong twine (heav}^) strings about eighteen inches long. With the scalpel make a median longitudinal incision in the skin and fascia over the sternum. The incision extends from the root of the neck to the end of the xiphoid cartilage. When the fascia and muscular layers come into sight a number of blood vessels will be seen passing mesially in pairs to the midline of the sternum where they pass into the chest. Do not cut these vessels if it can he avoided Fig. 104. — Bandage :aw. (which is sometimes impossible). In the center line it is usually possible to cut between the ends of each pair of vessels and thus avoid much hemorrhage. If a vessel is cut clamp it with a hemostat. The bleed- ing should soon cease. Have plenty of absorbent cotton (in small wads) at hand to sponge off the operative field. When the center line of the sternum is reached then take a saw (Fig. 104) and saw open the chest as shown in Fig. 105. Start the artificial respiration as soon as any open- ing is made into the chest. It is exceedingly important to keep the incision in the center line. If this is done prac- OPENIlSrG TPIE CHEST 109 tically all important blood vessels will be avoided. Just inside the chest the mammary vessels will be fonnd on each side of the midline. These vessels shonld be sepa- rated, each pair remaining attached to the under surface of its corresponding side of the sternum. If one of these vessels is cut it must be quickly caught with a hemostat and then a string is pushed (with the large sharp-pointed forceps) through the chest wall close to the lateral sternal Fig. 105. — Method of opening the chest by a median incision. border and the end brought around inside the chest. This string is now tied firmly and should shut off the vessel on one side of the cut place. But a second string is generally needed on the opposite side of the opening in the vessel to prevent hemorrhage from the other end of the vessel. All hemorrhage shoidd he checked before one proceeds with the experiment. 'When all bleeding has stopped then (with the forceps) pass the four large twine strings through 110 EXPERIMENTAL PHARMACOLOGY tlie margins of tlie chest Avails as shown in Fig. 106. Tie these ends, draw the chest wall open, and fasten the strings to the operating board as shown in Fig. 107. This fully exposes the lungs and the heart which is cov- ered by the pericardial sac. Did you see the anterior mediastinum! What became of it! With scissors open the pericardium in the midline. Then bring the cut edges of the pericardium out laterally and sew them (with two or three stitches on each side) to the chest wall. This forms a kind of hammock in Avhich the heart lies. The animal must be given sufficient ether to keep it quiet all the time. Observe carefully the beating of the heart and the movements of the lungs. Did the blood-pressure fall much when you opened the chest? It should not. Does the heart rise and fall as the lungs are inflated and de- flated? If so, try to reduce the extent of inflation a little and see if the animal does well (blood-pressure remains normal and convulsive movements do not appear). This rise and fall of the heart is the most troublesome thing concerned in the taking of heart tracings. Now take the cardiometer (Fig. 108) and stretch the rubber membrane outward from the opening, rolling part of the edge of the membrane back over the metal rim. Now place the cardi- ometer down over the heart (ventricles only, see Fig. 107) and bring the membrane down to the auriculo-ventricular groove. Roll the edge of the membrane off the metal part and allow the opening in the membrane to close around the auriculo-ventricular groove. Does the blood-pressure re- main normal? If not, wait a little and if necessary re- adjust the cardiometer. Connect the cardiometer tube with a recording tambour which may write either above or be- low the blood-pressure, depending on whether the pressure is low or high respectively. Adjust all writing points and take two or three inches of ''normal" tracing. The cardi- ometer record should be one or two inches in amplitude. Fig. 106. — Method of exposing the left pulmonary artery and vein. /,, linig. P. phrenic nerve lying on the pericardium (H) over the heart. D, the diaphragm. CARDIOMETER TRACINGS 111 Stiniulate one vagus nerve and see how this affects the tracings. Allow the heart to recover and take two inches more of "normal" tracing. Now crowd on the ether and note the effect on the pressure and cardiometer tracings. What does the cardiometer tracing show with respect to the heart? Be sure you describe this fully and correctly in your notes. Fig. 107. — Method of applying the cardiometer over the ventricles. Artificial respi- ration is carried on either with a hand bellows or by an artificial respiration machine. Tiie ether bottle has a by-pass so the amount of anesthetic can be regulated. The excess air escapes through the tube in the straight end of the tracheal cannula which is regu- lated by the screw clamp to give the desired amount of expansion and exhaustion of the lungs. Allow the animal to recover and then give it some chloro- form. How does this compare with ether? Now inject one-half cubic centimeter of adrenaline. How does this affect the heart? Is the drum going fast enough to show the indiAddual heart beats? Allow the animal to return to normal and then give it 112 EXPERIMENTAL PHARMACOLOGY some ethyl bromide. How does this affect the heart? In- ject a little adrenaline and let the animal recover. (It will be interesting to try ethyl chloride also. It can be sprayed into one of the rubber tubes going to the tracheal cannula. To do this an extra T-tube may be placed in the circuit.) Fig. 108. — Cardiometer. (See also Fig. 143.) 7. Dissection of Pulmonary Artery and Vein. — Remove the cardiometer and cut the stitches that hold the peri- cardium to the chest wall. Pull the pericardium and heart all over toward the right side of the animal. Observe the left pulmonary veins at the root of the lung. Observe Fig. 106 closely. At the base of the heart observe the aorta passing back posteriorly and then turning caudalward. In the hollow of the arch of the aorta between it and the heart a curved eminence covered with white fascia will be seen coming from the base of the heart and passing down- w^ards, outwards and backwards into the lung beneath the most prominent pulmonary vein. With a blunt probe care- fully dissect away some of the fascia over the curved emi- NITROUS OXIDE^ CARBON DIOXIDE, OXYGEN 113 nence, and the left pulmonary artery can be seen passing out into the base of the lung. Place an aneurism needle beneath the artery, raise it up and clear a section of the artery about three-fourths of an inch long with the probe. Could you put a cannula into this artery and record the pulmonary blood-pressure? The heart will probably have ceased beating by this time. If it has not, stop the respira- tion and let the animal die. If time 'permits it ivill he very instructive to try to revive the heart hy massage and by injecting adrenaline. Keep up the artificial respiration during these efforts. EXPERIMENT VI. Nitrous Oxide, Carbon Dioxide, Oxygen. (Frog: Central Nervous System.) 1. Place a frog in a one pint milk bottle as shown in Fig. 109. Arrange a nitrous oxide tank (and an oxygen tank also if the laboratory can afford one — if not omit the oxy- gen) as shown in the illustration. The apparatus shown in Fig. 110 may also be used if a nitrous oxide tank is not available. Observe (and count) the rate of the frog's res- piration, lymph heart beats and heart beats. Note the size of the pupils, position which the frog assumes, etc. Now open the N2O tank a little and run into the bottle a very small amount of the gas. Make a note of the time of day. The outlet must he opened as the gas is run in, for these tanks may have 1000 pounds or more pressure to the square inch and Avould quickly burst the bottle or blow out the cork. Watch the frog carefully as it begins to breathe the gas. Does it show any signs of suffocation? There Avas already sufficient oxygen in the bottle to run the frog some time. Gradually run in more NoO and watch carefully for the first symiDtoms sIioaati by the frog. As the atmosphere in the bottle becomes more and more filled 114 EXPEKIMENTAL PHAEMACOLOGY with the gas the frog will manifest distinct s^Tuptoms. How long does it take to completely anesthetize the ani- mal? When this stage is reached count the respirations, lymph heart beats and heart beats. Inject a little oxygen from time to ^ime and see if the animal comes ont from Wheel wrench \ Fig. 109. — Administration of nitrous oxide or oxygen to a frog. under the anesthetic. As the oxygen increases in the bottle the frog will recover. How long does this take and how long a time is required to anesthetize the frog in the first place? How does this anesthetic compare with ether or chloroform or ethyl bromide? 2. Place another frog in the bottle. Note the time of l^ITROUS OXIDE ANESTHESIA 115 day. Turn on the N2O and fill the bottle at once with this gas (washing most of the air out of the bottle with the N2O). How long does it take to anesthetize the frog? When Fig. 110. — Method for making, purifying and administering nitrous oxide to a frog. Strong solutions of ferrous sulphate, sodium hydrate and concentrated sulphuric acid are placed in the wash bottles. Fig. 111. — Yoke for tanks of oxygen, nitrous oxide or carbon dioxide. These yokes are attached to the tanks and a rubber tube is slipped over the nozzle of the yoke. When the valve of the tank is opened a little the oxygen passes out through the tube. The yokes can be obtained of dealers in surgical supplies or from the I^ennox Chemical Company, Cleveland, Ohio (Price $ .75). the animal is deeply anesthetized remove it quickly from the bottle and see how long it takes for complete recovery. 116 EXPERIMENTAL PHARMACOLOGY Keep a record of these periods of time. Does the frog again become completely normal? 3. Place another frog in the milk bottle. Now inject CO2 Fig. 112. — A double yoke for holding gas tanks. Made by bolting together two bars of iron. Fig. 113. — Yoke for holding gas tanks. Made of gas piping and fittings (see chapter on shop work). into the bottle. This may be done from a tank or from a Guthrie generator (Fig. 114). Observe the effect on the IS^ITROUS OXIDE^ ETHYL CHLORIDE^ CARBON DIOXIDE 117 animal. How is the respiration affected? How does this compare with the action of N2O ? If you have oxygen, run some of this into the bottle and see if this counteracts the COo. Fig. 114. — Guthrie's carbon dioxide generator. Two quart milk bottles are used to hold blocks of marble and dilute acid {A) and the wash water (bottle B). EXPEEIMENT VII. Nitrous Oxide, Ethyl Chloride, Carbon Dioxide, Increased Atmospheric Pressure, (Decreased Atmospheric Pres- sure). (Frog, Guinea Pig, Rat, Kitten, or Pup.) 1. Place a frog and a guinea pig (or other small mam- mal — see that the frog is protected) in a large bottle ar- ranged as illustrated in Fig. 115. Open the outlet and run 118 EXPERIMEliTTAL PHARMACOLOGY some oxygen into the bottle. What effect does this have on the animals ? It is to be noted that this experiment permits comparison of the relative effects of the substances ad- ministered on warm-blooded and cold-blooded animals. The OuHeir Cebauer!s eihyl chlorid Vie 115.— Method for studying the action of nitrous oxide, ethyl chloride, carbon dioxide, oxygen, increased (or decreased) atmo'spheric pressure on warm and cold-blooaea animals. skin absorption or excretion of the frog should be held in mind. Increase the amount of oxygen in the bottle. Then with the greatest caution raise the oxygen pressure in the bottle by closing the outlet and opening the clip on the tube ATMOSPPIERIC PRESSURE CHAXGES 119 going to the manometer while more oxygen is run in. Do not blow out the mercury by turning on the oxygen sud- denly. What effect has this increased pressure on the ani- mals 1 2. If a suction pump (or negative air pressure) is avail- able this may now be used. Open the outlet and connect this to the suction pump or negative pressure faucet. Open the clip to the manometer and exhaust the air in the bottle as many centimeters of mercury as the oxygen pressure has been raised. What effect has this on the animals ! 3. Wait a few minutes to note how the animals act and then again open the outlet and equalize the pressure inside and outside of the bottle. Roll up four or five sticks of sodium or potassium hydrate in wire gauze and put them in the bottle in such a position that the aninials cannot touch the alkali. What is the purpose of this? Be sure the alkali does not rest directly on the bottom of the bot- tle. Why? Allow the animals to become quiet again and then begin to gradually run N2O into the bottle, leaving the outlet open as gas is injected. Bring on the anesthesia by very gradual degrees and do not excite the animal if pos- sible. Do you notice any symptoms of somnolence in either animal? Or do you note s3^mptoms of excitement and con- vulsive jumping-like movements? After the animals be- come completely anesthetized begin to admit oxygen. How long does it take to produce complete anesthesia? Be care- ful that the oxygen does not become too low. If this occurs one animal may die. Which one? Is it possible for 3^ou to estimate how much oxygen (i. e., what per cent) you admit by closing the outlet and raising the atmospheric pressure in the bottle a given number of millimeters of mercury? Try to so balance the proportions of N.O and oxygen in the bottle that you can maintain a regular anesthesia in the animals for ten or fifteen minutes. 4. Now gradually admit more and more oxygen and note 120 EXPERIMENTAL PHARMACOLOGY carefully the recovery symptoms. What principles are in- volved in nitrons oxide analgesia or anesthesia ? How long does it take the animals to become normal! How does this compare with ether? 5. Eemove the alkali and allow the animals to become normal, or much better, get two fresh animals (a small tur- tle may also be included if the bottle is large enough) and then with the animals in the bottle run in a little CO2. Note the changes in rate and depth of respiration if any occur. Add more CO2. Can you produce an anesthesia with 00^.: Read this up in your text. Compare the symptoms in the two (or three) animals. Allow the animals to recover. 6. Paul Bert's Experiment. — Eeplace the alkali in the bottle and again run NaO into the bottle but leave the outlet open. In this way wash out the air and obtain almost a pure atmosphere of N2O. Bo not ivaste any more gas than is necessary. (As soon as marked symptoms of asphyxia ap- pear add a little oxygen.) When nearly all of the air (nitro- gen) has been run out of the bottle then close the outlet and wait a little if the animals are not unconscious and do not show too marked s>miptonis of asphyxia. Then slowly raise the pressure in the bottle by admitting oxygen. Paul Bert found that in an atmosphere consisting of eighty per cent N2O and twenty per cent oxygen, but with the pressure raised one-fourth above the normal atmospheric pressure, a complete nonasphyxial anesthesia could be produced and maintained indefinitely. Can you repeat his experiment? What gas does an animal give off in its expired air? What is the fate and mode of excretion of absorbed nitrous oxide? In what form is it carried in the blood? Plow does this compare with ether and chloroform or ethyl chloride or ethyl bromide? What is the purpose of the alkali in these experiments ? 7. Allow the animals to recover (or obtain fresh ones). Place them in the bottle (the alkali should also be in) and CLOSED METHOD OF AIS^ESTHESIA 121 then inject a small amount of ethyl chloride vapor. This is best done with a Gebaner tnbe as shoA\Ti in the picture but other containers which may be used are also in the market (Fig. 54). If ampoules are used the neck should be tiled a little and then the entire neck end of the ampoule is in- serted like a cork (air tight) into the rubber tube going into the bottle. The outlet is opened and the neck of the ampoule is snapped off by bending the tube. The ethyl chloride is very volatile and at once rushes into the bottle. Wait a lit- tle while for the drug to act. It generally acts fairly rap- idly but ma}^ require a little time for diffusion through the bottle and absorption into the animals' blood. How do the s^anptoms compare Avith those produced by ether or chloro- form! How long does it take to produce complete anesthe- sia ? If 3^ou add oxygen as needed, how long can you keep up this anesthesia with one dose of ethyl chloride ? Do not give more ethyl chloride than is absolutely necessary or you may kill one or both of the animals. "Somnoform" or Brugg's mixture may be used also if the drugs are available (they can be bought from dental supply houses and are put up in ampoules). Similarly ethyl bromide may be used. A small quantity of this may be poured into the bottle through a funnel. Save all animals used until next day and observe if any permanent injury has been done to them. EXPERIMENT VIII. The Closed Method of Anesthesia. For Ether, Chloroform, Ethyl Chloride, Ethyl Bromide, (Nitrous Oxide), ' ' Somnof orm, " etc., with Oxygen. Student Method. (Dogs or Cats.) 1. Observe carefull}^ the construction of the apparatus shown in Fig 116. Arrange the table for operative work as shown in Fig. 117, but omit the ether bottle, substituting therefor the apparatus sho^vii in the illustration. Into the 122 EXPERIMENTAL PHARMACOLOGY bottom of the large pan shown in Fig. 116 pour a layer of strong (not saturated) sodium (or potassium) hydrate solu- tion al30ut three-fourths inch deep. The solution must not he IV arm. Stretch the thin rubber bath cap air-tight over the rim of the large pan as illustrated. Thereafter do not upset the pan nor splash out the solution. If the dog strug- Wheei wrench Fig. 116. — Apparatus used for closed ether (ethyl chloride, chloroform, nitrous oxide, etc.) anesthesia. A large, shallow, round cake pan covered by a thin bath cap holds the vapors or gases. The animal breathes into and out of the pan through a spout. Strong sodium (or potassium) hydrate solution (which must be cold) in the bottom of the pan absorbs the CO2 eliminated. A diagrammatic view of the pan as seen from above is shown in Fig. 118. Oxygen is admitted as needed by the animal from the tank (or from the apparatus shown in Figs. 176 and 177). Ether or chloroform or ethyl bromide may be injected through the burette. Ethyl chloride can be sprayed in through one of the inlets. (See Journal of Laboratory and Clinical Medicine, 1916, ii, p. 94; also ibid., 1916, ii, p. 145.) gles this might occur, but such an accident is much more likely to happen as the result of awkwardness. Etherize the dog on the floor in the usual manner (Fig. 71). Then place it quickly on the operating board, tie it do^vn and insert the tracheal cannula. The straight end of the can- CLOSED METHOD OF AISIESTHESIA 12.5 iiula carries a short piece of rubber tubing and a screw clamp. Close the clamp and insert the side tube of the can- nula into the hole in the cork, which closes the large spout from the pan. Run enough oxygen into the pan to lift the bath cap up about one inch above the top of the large pan. From the burette it will probably be necessary to inject about one or two cubic centimeters of ether into the pan be- fore the anesthesia becomes deep enough. Do not be in too much of a hurry to add this ether, for the anesthesia should not be any deeper than is necessary. Hereafter the Wash jar Ether bottle injecting burette 5teft\ogr3ph Ligatures Artificial respiration Small table r.nn. Liqa tares 6in.Tinner's snips Trephine Fiij. 117. — Arrangement of the apparatus on the table for performing an experiment. anesthetist merely watches to keep a fair amount of ox^^gen in the pan and at long intervals from one-half to one cubic centimeter of ether may be injected if needed. The anes- thesia should remain perfectly constant and regular if no leaks are present in the apparatus. These are not difficult to avoid. If the experiment is performed correctly the stu- dent will be impressed with the ease and certainty with which a perfect anesthesia can be maintained for long per- iods of time. If too much ether (or other anesthetic) gets into the pan open the screw clamp on the tracheal cannula 124 EXPERIMENTAL PHARMACOLOGY and allow some of the vapor to escape. Then refill the pan with oxygen. This method is new. Students are advised to study it carefully. Is there any danger of the respiratory medium becoming too moist? Are any volatile poisons given off in the breath that might accumulate in the breath- ing space? Will the smaller percentage of nitrogen in the air breathed by the animal influence the anesthesia ? Will Eiher inlet Oxyqen inlet Flanqe < Lower flanqe Fig. 118. — Diagrammatic view of the pan as seen from above. the respiratory medium become too warm! Could you counteract this? How is the ether excreted! How is it absorbed and carried to the tissues? W^hat combinations does it form in the body? 2. Arrange to record blood-pressure and respiration (stethograph). Connect an injecting burette to the left femoral vein. Isolate and ligate loosely (but do not clamp or injure) the right femoral artery. Place some adrena- line (1:10,000) solution in the burette. Or epinine solu- tion (1:1000, Burroughs, Wellcome and Co.) may be used. CLOSED METHOD OF ANESTHESIA 125 126 EXPERIMENTAL PHARMACOLOGY Arrange all writing points on the drum and take a few inches of normal record. How does this record of blood- pressure and respiration compare with that obtained when you used an ordinary ether bottle to maintain the anesthesia? 3. While the anesthesia is moderately light but per- fectly regular, inject just enough oxygen to run the animal for about three minutes. Then with a screw clamp close off the injecting (oxygen) tube and change the oxygen Fig. 120. — At the place marked "normal" the animal was breathing naturally. No drug had been administered and the animal was lying quietly on the table. At the point indicated some nitrous oxide was given. The respiration at once becomes deeper and more rapids tank for a nitrous oxide tank. Open the screw clamp on the injecting tube and run in as much N2O as is possible without stretching the bath cap. This should be perfectly free to rise and fall and should not be under any tension. If the cap is stretched the animal cannot breathe well for the mechanical obstruction and may die. The drum runs at a slow speed as the N2O is run in. How does this affect the blood-pressure and respiration! How does this com- pare with the injection of a drug through the femoral vein? CLOSED METHOD OF AISTESTHESIA 127 What is the action of N2O on the heart I Is the anesthesia deepened? 4. After a sufficient time open the side clip from the pan and empty out the mixed gases. Close the clip and run in some fresh oxygen. Take some more normal record and then from a Gebauer ethyl chloride tube inject through the outlet tube of the pan a small amount of ethyl chloride. Fig. 121. — The animal was anesthetized with nitrous oxide. At the point indicated a little ethyl chloride was given (in addition to the nitrous oxide). The much more marked action of ethyl chloride on the blood-pressure and respiration is seen at once. Do not give too much. How does this affect the blood- pressure and respiration! Is the anesthesia deepened? Which is the more powerful, ether or ethyl chloride! Empty out the ethyl chloride and allow the anesthesia to become fairly light. 5. Eepeat No. 4, using ethyl bromide, ''somnoform" or Brugg's mixture instead of ethyl chloride. Do not give 128 EXPERIMENTAL PHARMACOLOGY more than one cubic centimeter of ethyl 'bromide (one-half cubic centimeter is mucli safer). This is a powerful drug. 6. After records are obtained empty out the vapors, open the screw clamp on the tracheal cannula and allow the dog to get fresh air for some time to recover. (The animal, of course, thus exhales the drugs into the open air.) 7. When the animal recovers close the tracheal clamp and let the anesthesia again become as regular as pos- sible. Now through the burette inject into the pan one- half cubic centimeter of chloroform. Do not give too much. Obtain a record and then empty out the vapor as before. How does this record compare with those obtained with the other drugs ? What conclusions can you draw concern- ing chloroform? What class of physicians make most use of chloroform? Can you use the closed method for anesthesia when the chest is opened? This is a good point for the student to consider. Does this method present any advantages over the use of an ordinary ether bottle ? What are the relative disadvantages? 8. Put about one cubic centimeter of chloroform into a good dental syringe carrying a small short needle. Now lift up the right femoral artery on an aneurism needle and at the same time let an assistant press down on the cor- responding vein to shut off its return flow. Now with great care slip the syringe needle endwise into the lumen of the artery. Loosen the tension on the artery a little and as the blood again flows through carefully inject the chloroform. Feel of the leg. Is there produced a pro- found change in the tissues? If not, repeat the injection into the other femoral artery. 9. Kill the dog by asphyxia. Open the abdomen and dissect out and examine the spleen, pancreas and left kid- ney. To what is the spleen attached? Place it inside an INTKATRACHEAL 1:^811 FFLATION 129 oncometer and close the abdomen with hemostats. Could you do. this in a living dog? Eemove the oncometer and put away all apparatus. Do not forget to wash out the tubing connecting the carotid to the manometer. EXPERIMENT IX. Intratracheal Insufflation. 1. Study carefully the principles involved in the con- struction of the apparatus shown in Fig. 122. A constant Fig. 122. — Apparatus for intratracheal insufflation. The tip of the catheter should Ibe cut off just back of the "eye." Any similar sized rubber tube may be used instead •of the catheter. The outer diameter of the tube should be about one-half (or a little Jess than) that of the inner diameter of the trachea. ■current of air passes into the tube at the extreme right of the picture. By turning the small lever on the side of the -ether valve, part or all (or none) of the air can be made to pass over the ether and then out through the rubber 3 M O ^_ y» o> o 1 -1 ^ (n 180 EXPERIMENTAL PHARMACOLOGY mination and proceed with the remaining observations. To determine marked changes in the rate of oxygen con- sumption by the animal an apparatus similar to that shown in Fig. 172 is required. (See also Fig. 175.) This con- sists essentially of the anesthetic apparatus shown in Fig. 116 but with the addition of a four or six inch thin alumi- num (or pasteboard) disc which rests (stuck on with muci- Olfactory lobe Crucial fissure Lateral sulcus Suprasylvian sulcus Great longitudinal fissure Gyrus Margin alls Gyrus Suprasylvius Gyrus Ectosylvius Vermis of cerebellum Medulla oblongata ist cervical nerve Spinal cord White matter of cord Fig. 171. — Dorsal surface of the brain of a cat. (Partially adapted from Davison.) Lateral lobe of cerebellum Posterior pyramids Gray matter of cord lage) on top of the bath cap covering the large pan in the bottom of which is placed strong (not saturated) sodium hydrate solution [Ca(0H)2 may also be added if desired] to the depth of about three-fourths or one inch. Oxygen is run into the breathing pan from; the tank as needed. In the center of the aluminum disc are two small holes in which is tied a twine string about four feet long. One, two or three bull-dog forceps must usually be laid on the top of the disc to cause it to move down readily as the dog in- spires. As the dog expires the disc moves upward. These RATE OF OXYGEN CONSLTMPTION 181 ^ooc.c. cylinder Fig. 172. — Arrangement of apparatus for recording and measuring the rate of oxy- gen consumption. (See also Fig. 175.) The side tube of the tracheal cannula opens into the interior of the large square pan. The trough (Fig. 173) is filled with water and the breathing pan dips up and down in the water. A layer (3/4 inch deep) of strong sodium or potassium hydrate solution is placed in the bottom of the inner pan to absorb the CO2 exhaled by the animal. If the clip on the tube leading from the graduated cylinder to the pan be closed while the oxygen tank is opened a little, the water in the cylinder will be forced up into the pressure bottle. When the cylinder is thus filled with oxygen the tank valve is closed. The oxygen remains stationary in the cylinder but can he immediately run into the pan by opening the clip on the com- municating rubber tube, as the water in the pressure bottle will quickly run down and displace the oxygen which is thus forced out into the pan. This causes the writing lever on the drum to make a sharp rapid descent. As the animal uses up the oxygen and the breathing pan slowly descends the writing point on the drum slowlv goes up. (See Fig. 175.) - 5 1 182 EXPERIMENTAL PHARMACOLOGY fairly rapid movements up and down correspond to the regular respiratory movements of the animal. But in ad- dition to these rapid movements a larger and more pro- Breafhinq pan Inner pan Trouqh (water) Outer pan Respiratory openinq NaOH solution Hinqe rod Oxyqen inlet Ether inlet T' -irH3iis.chi. Fig. 173. — Inner construction of the pans shown in Fig. 172. These pans can be made of sheet brass or tinned iron. Pans which can be used for the purpose can ofteri be purchased at a hardware store (or a ten cent store). (See Journal of Laboratory and Clinical Medicine, 1916, ii, p. 145; also ibid, 1916, ii, p. 94.) Stopper _S Inches 13 xlZ Fig. 174. — Lateral view of a cross-section of the apparatus shown in Fig. 172. The breathing pan is best made of very thin sheet brass (which is easily soldered and is not affected by alkalies as is aluminum). The pan should be carefully counterpoised with an adjustable weight. The dimensions are indicated in inches on the scale. longed movement of the disc occurs. This corresponds to the injection of oxygen from the tank into the pan when the disc will be lifted up a considerable distance (perhaps EATE OF OXYGEN CONSUMPTION 183 one inch), and then to the gradual consumption of this oxygen by the dog during which interval the disc will be falling (one inch). During all this time the exhaled car- bon dioxide is being absorbed by the alkali solution. The twine string attached to the disc passes over two pulleys (one inch brass wheels — these should be of the best quality and can be bought at any good hardware store for about twenty or thirty cents apiece). The opposite end of the Fig. 175. — A simpler arrangement for recording the rate and amount of oxygen consumption by an animal. (See also Fig. 172.) There is more chance for "lost mo- tion" by use of the flexible bath cap over the pan than with the apparatus shown in Fig. 172. (See Journal of L,aboratory and Clinical Medicine, 1916, ii, p. 94.) string is clamped on to the long arm of a frog heart lever by means of a bull-dog clamp. Two clamps may be needed to draw the lever doA\m readily. These clamps serve not only to hold the string to the lever but act as balancing weights as well. The heart lever writes at the top of the drum, below this is the blood-pressure (mercury ma- nometer), next the respiration (tambour connected to the 184 EXPERIMENTAL PHARMACOLOGY stetliograph drum), and at the bottom is the base line and time marker. The drum should have an approximately constant slow speed. The arrangement of the apparatus and records is shown in Fig. 175. The anesthesia should be fairly light and maintained solely with ether (since morphine is injected later). If the apparatus is in good condition the anesthe- sia will be approximately constant. Observe the character of the tracing on the drum, also Fig. 180. The thin narrow curved lines in the oxygen consumption record are made while the drum is standing still. This narrow line repre- sents the downward movement of the lever as the pan is filled with oxygen. The extent of this down stroke is op- tional but should be regulated by the tension of the oxygen on the bath cap. The cap should not be filled so full as to stretch it, as this would cause too great a mechanical obstruction to the breathing of the animal. This must be carefully avoided. When the pan is filled sufficiently with oxygen the writing lever will have descended to a certain level on the drum. This level marks what may be termed the lower base line for the ox3^gen record. In filling the pan mth oxygen at all later times see to it that the lever again descends to this same level as nearly as you can de- termine. This is done by watching the lever go down as oxygen is run in very cautiously. Conversely the highest point in the oxygen record may be called the upper base line for this record. If while the drum is stopped the lever be run doA\m to the lower base line by adding oxygen to the pan, then just as the lever reaches the base line the injec- tion of oxygen is stopped and the drum is started. (It is desirable that the drum start quickly and soon reach the maximum for that rate of speed.) As the drum runs the lever moves up and down a short distance rapidly at each inspiration and expiration. We are not much concerned now with these short, rapid movements as they correspond fairly closely with the respiration tracing from the stetho- THE GENERATION OF OXYGEN 185 Mercury bulb ^ ^:\r^^^ or funnel To anesfhefic device or to reservoir UmiA Fig. 176. — A cheap form of apparatus used for making pure oxygen. Sodium per- oxide is placed in the left hand bottle and water is allowed to drop slowly down on to the NaoQo from the mercury bulb above. Oxygen is liberated and at once bubbles over through the water in the wash bottle. In one experiment 74 grams of sodium peroxide generated sufficient oxygen to run a IS kilo dog for one hour. At the end of this period the left hand bottle was exchanged for a second (quart milk bottle) containing a sec- ond 74 grams of sodium peroxide and this again liberated sufficient oxygen to run the animal another hour. In this experiment the closed anesthesia apparatus shown in Fig. 116 (see also Fig. 17S) was used. It is advisable to use some kind of reservoir to catch the oxygen generated as the rate of liberation cannot be controlled accurately by the addition of the water. 186 EXPERIMENTAL PHARMACOLOGY graph drum. These movements do, however, with many drugs, record very profound and striking changes in the bronchioles. (Can you detect any evidence of this when morphine is injected into the femoral vein!) But the im- portant point in the oxygen record is the gradual rise of the lever as the oxygen in the pan is consumed by the dog. The rate of this rise determines the rate of oxygen con- sumption. Watch carefully and when the lever reaches a satisfactory altitude (this will vary with each experiment and the student with a little practice can estimate about when to stop), which will generally be about two inches if a large drum is used (lower and less magnified if a small drum is used), then suddenly stop the drum and at Rubber bath cap Cas iniet \9i//7. Cal^e psn Flan(jeon pan Added flanqe 03S out lev Fig. 177. — A simple gas reservoir made from a very shallow, wide, round cake pan with two spouts soldered into the walls. A large bath cap is stretched over the pan and serves to form an adjustable gas reservoir suitable for use with the apparatus shown in Fig. 176. A small spirometer (1 or 2 gallons) may also be used as a reservoir. The spirometer should be delicately counterpoised as the oxygen is not delivered from the wash bottle under a high pressure. A large, thin walled rubber bag may also be used. once run a fresh sujDply of oxygen into the pan. The lever comes down and when the base line is reached stop the oxygen inflow and immediately start the drum. (If the drum is exceedingly slow the oxygen can be run in while the drum is turning. This is very convenient.) When the lever again reaches its former high point stop the drum and at once reinject ox^^gen. This gives a saw-tooth like record. And the distance between each two consecutive teeth or descending narrow lines in the record gives a measure of the relative amount of oxygen consumed dur- ing that period of time. If a drug which slows the con- OXYGElSr DETERMINATION 187 sumption of oxygen is given, then the distance between the consecutive descending lines will be increased; while a drug which increases the relative consumption of oxy- suction apparatus -Large glass tube or Liebig condenser with graduated scale (c.c.) By pass Fig. 178. — Dreser's arrangement of apparatus for recording the volume of air ex- pired by an animal in a given length of time. The large glass tube (or Liebig con- denser jacket; is filled with water which is supported up in the tube by the pressure of the atmosphere. The by-pass is closed and the clip on the tube leading from the milk bottle inspiratory valve is removed. When the animal inspires, air enters the in- spiratory tube, bubbles through the water in the bottom of the bottle and thence passes to the lungs. At expiration the air passes through the straight course of the tubes to the large glass jar or dish and thence is liberated in the lower end of the large glass tube. The exhaled air then quickly displaces the water and rises to the upper part of the large glass tube where it can be measured on the scale. 1^ EXPERIMENTAL PHARMACOLOGY gen will cause a decrease in the distance between consecu- tive descending lines. If the instructor desires it is an easy matter to place a gas measuring device in the path of the oxygen inflow tube To recording fdmbour Mercury bulb ^ Bladder cann ula ^niiiiiijjwwwm) -> info beaker or to recorder Urachus Loose liqafure Fig. 179. — Technic for inserting a bladder cannula or for connecting a mercury bulb to record bladder contractions. (For discussion see text.) and measure the amount of oxygen run in at each filling of the pan (see Fig. 172). This is instructive and is a valuable procedure in the beginning, but with a little prac- tice the operator will be able to attain sufficient accuracy RATE or OXYGEN CONSUMPTION 189 by simply watching the lever as it writes on the drum. A monkey wrench is better than the regular wheel wrench to control the valve on the oxygen tank where careful regu- lation is needed. It is very desirable to have the tank fastened down with a clamp to the table (see Figs. 112 and 113). To obtain urine for tests the abdomen is opened over the bladder which is caught in a hemostat at the urachus (Fig. 179). The bladder is then raised a little and a second hemostat is clamped on the opposite side of the urachus in such a manner that an opening can be cut with a scalpel or scissors just between the tips of the hemostats. Be- fore this opening is made place a twine string around the upper part of the bladder (just below the points of the hemostats) and tie it loosely. Open the bladder (do not allow any urine to escape or blood to run doA\ai into the bladder if it can be avoided) and quickly insert the blad- der cannula. Tie the ligature and replace the bladder within the abdomen which is closed by hemostats. Catch the urine in a beaker and test some early to see if it con- tains glucose. ^¥lien all apparatus is adjusted start the drum and take several records of the ox^^gen consumption in order to become familiar with the method and to get some nor- mal records. Your success mil depend largely on your ability to determine exactly when to stop and start the drum and to judge when the lever has gone high enough. This is the most diffcult part of the experiment and should alivays be done by that member of the group who is best able to carry out this work. Your "normal" oxygen records should be almost exactly alike both in form and in the distance the^^ occup}^ on the drum. Inject one cubic centimeter of morphine. Watch the oxygen records closely and make your changes promptly. When the records all return to normal inject three or four 190 EXPERIMENTAL PHAEMACOLOGY cubic centimeters and record the results. Do you get what you expected? Does the anesthesia remain regular? How are the respiratory movements affected? Does the rate of oxygen consumption correspond with the rapidity or slowness of the respiratory movements or with the height of the blood-pressure? Would you have expected these re- sults ? Now take one or two normal oxygen records and then when the oxygen lever is getting pretty well up to the top of its course inject one-half cubic centimeter of ad- renaline. Watch carefully to reset your oxygen record at the exact moment. Be sure before the adrenaline is in- jected that the rise in the manometer writing point ivill not interfere (catch) luith your oxygen lever. Watch your oxygen record closely and make the changes promptly. Take at least two or three minutes to record this after the adrenaline is injected. Do you observe any peculiar changes in your records? If not, wait a while and repeat the adrenaline injection. How does morphine affect the heart? Can you detect any change in the rate ? Give more morphine from time to time (two cubic centimeters per dose), and see if you can bring on a Cheyne-Stokes form of respiration. Does the anesthesia become any deeper? Examine the pupils carefully. Are they in the same condition as were those of the dog in Experiment XXV? Does this agree Avith the text-book descriptions? Inject as much morphine as you think (from the ap- pearance of the respiration, blood-pressure, etc.) the ani- mal can safely stand. You may not get a Cheyne-Stokes form of respiration, but many small repeated doses are very liable to bring it on. Variable but constantly repeated irregularities of the respiration often appear. Allow the animal to recover a little if it will and then inject codeine (two cubic centimeters — 1 c.c. =^ 5 mg.). Get a record of this and then increase the dose given. After a few injections (and within half an hour), marked symp- M' ACTION OF MOEPKINE ON OXYGEN CONSUMPTION 191 192 EXPERIMENTAL PHARMACOLOGY toms should appear. Test the urine for glucose. Is there any reduction? How do you account for this! Kill the animal with codeine. 2. If time permits carry out the following dissections. Fig. 181. — Record showing the action of adrenaline on. the rate of oxygen consump- tion, uterine contractions, blood-pressure and respiration. There is a slight slowing down of the rate of consumption of oxygen which is mainly concordant with the Period occupied by the fall in blood-pressure after tl:e large initial rise. (See Journal ot i^ab- oratory and Clinical Medicine, 1916, ii, 145.) Isolate both the internal and the external jugular veins on each side. (See Figs. 133 and 183.) Note carefully in just what portion of the neck tissues these vessels are PRACTICE DISSECTION 1^6 located. Could you pass a large needle in at the median incision in the neck and then push it out through the tis- sues in the side of the neck in such a manner as to in- clude both the jugulars on one side in a ligature threaded through the eye of the needle! If you should thus tie a ligature loosely around a portion of the tissues in the side of the neck (including both veins), and then should lift up with a moderate degree of pressure on the ligature, what eifect Avould this have on the back flow of blood through the veins to the heart? How much pressure does it take to shut off the flow through a vein? Carry your Cervical nerves Diaphragm Vaqo- symp. frunK-^ Cervical vertebrae Fig. 182. — Schematic representation of the origin, course and distribution of tiie right phrenic nerve in a dog. (Tlie origin varies in different animals.) dissection well down on to the longus colli muscle in the right side of the neck (Fig. 184) and find the right verte- bral artery. Pass a large aneurism needle under the ves- sel, lift it up and slip a ligature around it. What is the distribution of this vessel? Could you inject a solution from a hypodermic syringe into this vessel toward the head? How long a space would you have to operate on the vessel? If you do not find it readily, pick up the right subclavian artery and find the vertebral from this. Could you make the dissection tvitliout getting into the chest cav- 194 experimeinttal pharmacology ityf Pick up the right phrenic nerve. What is the origin of this nerve? If you do not find it readily open the chest and locate it on the pericardium at the side of the heart. Trace it from here back up into the neck. Could you cut both phrenics in the neck ivithoiit opening the chestf This is sometimes done to stop movements of the diaphragm when these interfere with certain records that are being made. EXPERIMENT XXIX. Morphine, Codeine, Pantopon, Heroine, Peronine, Dionine, Narcotine or Thebaine. (Spinal Dog: Bronchioles.) 1. This is a neAv field of experimentation for most med- ical schools. Many drugs act vigorously on the bronchioles and it is unfortunate for medical students not to have some opportunity to perform experiments to bring out these results, for the action of these drugs is often much more striking on the bronchioles (and perhaps frequently as important) than are the corresponding actions on the heart or other organs. Several methods will therefore be given in different experiments in order to give every lab- oratory a chance to carry out such experiments. The best (but perhaps the most complicated) method will be given in Experiment LXX. For peripherally acting drugs it is advisable to use spinal dogs. (Cats may also be used for this work but dogs are better.) Before starting the experiment be sure to arrange for a reliable source of artificial respiration. This should be from an artificial respiration machine, but a hand-bellows fixed to open only a given distance (to regulate the stroke) may answer. Etherize a dog and arrange it for a blood-pressure trac- ing. Place injecting burettes in connection with the fem- oral veins. One burette contains adrenaline (1:10,000), the other an opium alkaloid. Any one of those at the head Exijuqulzr vein Carotid artery - Int. ju^u/ar v. Transverse scdpular sna cervical ascenc/m^ arteries Subclavian vein Fig. 183. — Dissection of the lower part of the neck and upper part of the chest on the right side in a dog. (Modified from Schniiedeberg.) Ext. juqukr vein -^ Carotid artery — v^ Int jugular vein-^^^ Va(]o sympathetic nerve — ^ Vertebral artery^ vein ^ "^ Deep cervical artery —^ Transverse scapular ^ , , ascending cervical drteries- \ Rt subclavian artery^ Rt mammary artery Fig. 184. — Dissection of the lower part of the neck and upper part of the chest and of the axillary region in a dog. (Modified from Schmiedeberg. ) BRONCHIAL ACTION OF OPIUM ALKALOIDS 195 of this section may be used, but either heroine, codeine or dionine will probably give the best results. Be sure the drug is fresh and of first-class quality. Codeine possesses some advantages in this respect. The strength of the solu- tion chosen should be five milligrams to the cubic centi- meter. With great care to avoid opening the chest at the apex dissect down on the right side of the neck (see Experiment XXVIII, 2; also Figs. 183 and 184), and pick up the right vertebral artery. Place a ligature around the vessel and tie the ligature once loosely. The ends of this ligature are brought together and clamped Avith a bidl-dog so it can be found readil}^ Noav with a large (five or six inch) Fig. 185. — Large needles for sewing with heavy twine. needle (Fig. 185) pass a ligature of heavy twine through the tissues in the side of the neck in such a manner that both jugular veins will be included. The carotid artery and vagus nerve must not be included. The ligature passes out through the skin at the side of the neck. The two ends of the ligature are brought together and tied once loosely and clamped with a hemostat. Another ligature is simi- larly placed on the opposite side so that in this way the chief venous return flow from the head can be quickly clamped off. Now fill a small syringe (two cubic centi- meters) of good quality with chloroform. The point of the syringe should be as small and as short as possible. A cheap syringe is very liable to leak chloroform. Get all apparatus properly adjusted and then lift up the vertebral arter}^ on an aneurism needle and insert the syringe point 196 EXPERIMENTAL PHARMACOLOGY into the lumen of the artery pointing toward the animal's head. This should be done with great care and no chloro- form should he emptied out in the ivall of the vessel. The assistant now takes hold of the ligatures (hemostats) that Fig. 186. — Brass tube (7yi inches long and ^i inch in diameter) with (separable) spear point to be passed through the chest for recording lung volume changes. The holes cover a space about 2>4 inches long. control the jugular veins and gets ready to close off (by pressure) these vessels. It is advisable for a second as- sistant to put a hull-dog clamp on the left carotid at this moment. The operator then injects the chloroform (one Fig. 187.- — Arrangement of animal for recording lung volume changes. (For descrip- tion see text.) or two cubic centimeters) into the vertebral artery. This chloroform quickly reaches the brain and destroys all parts with which it comes in contact. The blood-pressure falls CHLOROFORM INJECTIOIST INTO VERTEBRAL ARTERY 197 rapidly and artificial respiration must be started at once. Close off the jugulars immediately and tie the ligatures firmly. Be sure the lungs are well inflated but do not burst them. Remove the ether quickly as no further anesthetic is needed. If your first injection does not succeed well, make a second one into the left carotid artery. Luckhardt Cenhqrade fhermomei-er 7? TtHalleek- Fig. 188. — Arrangement of apparatus for keeping the systematic blood-pressure at a constant level during the action of drugs which produce marked changes in the caliber of the arterioles. The cannulas in the femoral arteries are connected with a siphon tube which dips in a beaker containing warmed salt solution (or whipped or hirvidinized blood). Hirudin is injected intravenously to prevent clotting of the blood. The alti- tude of the beaker above the animal regulates the pressure which can be maintained in the blood vessels. This is read off from the mercury manometer. If the vessels contract blood is forced over into the beaker but the arterial pressure does not rise. When the vessels (arterioles) dilate the blood siphons back into the femoral arteries. has succeeded well by making injections into the carotid artery alone. (Some workers have obtained good results by injecting a three per cent suspension of starch gran- ules into the carotid artery.) This is easier than inject- ing the vertebral on account of the dissection, but the me- dulla may not be well reached thronoli the carotid. In a 198 EXPEKIMENTAL PHARMACOLOGY Fig. 189. — This lung volume and blood-pressure record was taken from a dog by the use of the blood-pressure regulating device shown in Fig. 188. The lung record was taken by means of (positive) artificial respiration (using the tube shown in Fig. 186 and the method illustrated in Fig. 187). The purpose of the, tracing was to show that con-- traction or dilatation of the bronchioles is practically entirely independent of the changes in systemic blood-pressure. The slight variations in the course of the carotid pressure tracing were due to the great suddenness of the extensive changes in caliber of the arterioles produced by the action of the drugs, i. e., the contraction of the arterioles occurred slightly quicker than the blood could siphon over through the small pointed cannulas into the beaker. But if no equalizing device had been used the carotid pressure would have risen above the top of the lung tracing. BRONCHIAL ACTION OF OPIUM ALKALOIDS 199 spinal dog the blood-pressure will be about one inch above the base line on the drum. Do not be alarmed so long as it remains this high and is not falling. If any of the chloro- form gets back to the heart, the dog may die quickly. If the animal is about to die inject one-half or one cubic ^m ^|_^""»*«- daiQij ti^y^u ^nyjurr-xl/L Fig. 190. — Blood-pressure and bronchiole tracings showing the action of morphine in a dog. These tracings were made by the method described in Experiment LXX, page 287. centimeter of adrenaline. AVhen the blood-pressure is reg- ular, then pass a brass tube (Fig. 186) directly through the chest walls at the level of the ventral border of the sixth intercostal space (see Fig. 187). To do this make 200 EXPEKIMENTAL PHAKMACOLOGY an incision through the skin on each side in the proper place. Then pnsh the spear point of the tube right through the muscular walls from side to side. Do this as the lungs are deflated. Be sure the tube passes inside the chest cav- ity and does not slip along under the parietal pleura just mm I |'i|1ii s^Mi f I IfufiMlM illiUJ (ii (Si i I 1 , r\ nnn J- 1 0,000 mmmm j,^^i -^t^ft-e.- S ^.exi^crv^^jiJ. Fig. 191. — Blood-pressure and bronchiole tracings showing the action of pantopon. (Pantopon, or pantopium hydrochloricum, is the hydrochloric acid extract of the total alkaloids of opium — very soluble in water, sold by I-Ioffmann-L,aRoche Chemical Works, New York.) BKONCHIAL ACTIOjST OF OPIUM ALKALOIDS 201 below the sternum. Eemove the spear point from the tube and place on this end a piece of rubber tubing carrying a screw clamp. This is to regulate the amount of air going into the tambour which is attached to the other end of the tube. Clamp the brass tube tightly in the chest walls iniiniiiiiiiiiininiii .2al — >>i 3c^ ^&^^^^/^^-9.U-(^^, iUHRS^BI^ „^ .^1^- „1 92.— -Blood-pressure and bronchiole tracings showing the action of peronine. iipinme tailed to cause dilatation of the bronchioles and the animal died of asphyxia. 1. could easily have been saved by forcibly dilating the lungs mechanically to check the asphyxia. 202 EXPEKIMENTAL PHARMACOLOGY by hemostats on each side. The tambour should have a large bowl (three inches, see Fig. 14). Bring the writing point of the tambour on to the drum above the blood-pres- sure and adjust the tambour to give a tracing about two or three inches high. The force of the respiration may have to be changed to give this. The rate of inflations "'^'^■Yrwi'mm Fig. 193. — Blood-pressure and bronchiole tracings showing the action of dionine. Adrenaline caused a prompt dilatation. The method used is described in Experiment LXX, p. 287. should be about twenty or twenty-five times per minute. Start off the drum (slow speed) and take one or two inches of normal record. Then inject five cubic centimeters of the opium alkaloid solution. The blood-pressure falls at once but the heart should not stop. What does the lung BRONCHIAL ACTION OF OPIUM ALKALOIDS 203 volume show? Did you get what you should get? AVhen the action of the drug has become very marked inject one cubic centimeter of adrenaline. How does this affect the blood-pressure and lung volume? Does the one depend J-tO,OGO ^^^^^^^^^^^^i Fig. 194. — Blood-pressure and bronchiole tracings showing the action of narcotine. on the other? (They do not — each is mainly independent of the other; see Figs. 188 and 189). When the records again become normal then inject six cubic centimeters more of the opium alkaloid. Do you get a second lung volume tracing? Inject some adrenaline to 204 EXPERIMEE^TAL PHARMACOLOGY revive the animal. Now stimulate each vagus nerve in the neck to see the effect on the heart and lungs. What is the innervation of the heart and bronchioles! If the animal is still in a suitable condition, inject six cubic centi- meters of a different opium alkaloid. Do you get lung records'? Give some adrenaline to help revive the animal. The abdomen may now be opened by a three inch median fArs4i»\JU.<^\ \ rec iiimirftiiMiiiiiimnriiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii Fig. 195. — Respiratory and blood-pressure tracings from a dog showing the progres- sive actions of narcophine (Straub), narcotine and morphine. The peculiar irregularity of the respiration is developed early and leads to the Cheyne-Stokes type of respiration. What is the cause of Cheyne-Stokes respiration? Does the peripheral action of these drugs (note the size of the doses) have anything to do with the respiratory disturbances? The vagi were intact. longitudinal incision down near the pubic symphasis and the bladder lifted up as described in Experiment XXVIII, page 189. The animal will probably be dead by this time. Could you thus pick up the bladder and place a cannula in it in this manner in a spinal dog without letting the ani- ACTION OF CAiSTNABIS INDICA 205 mal die? How iniglit you do such an experiment and avoid opening the abdomen after the brain of the animal was destroyed! What are the main differences that you note between the reactions and vitality of a spinal dog as com- pared with a normal animal I Fig. 196. — Method of administering capsules, pills or tablets to dogs. The tongue is pulled forward and the prepared dose is dropped far back in the mouth. The jaws are held closed and the animal is gently slapped under the throat, or a little water may be given. The method illustrated is frequently used in testing (standardizing) cannabis indica preparations. The U.S. P. doses are: — fluidextract 0.03 cubic centimeter, extract 0.004 gram and tincture 0.3 cubic centimeter per kilogram of body weight, for small or medium-sized, smooth-haired (preferably fox terrier) dogs. Doses not larger than these should produce incoordination (best observed when the animal is standing still) and slight ataxy in walking. The animal should be kept in a quiet room and the symp- toms may not become marked (or even perceptible) for one or two hours. In three or foiir hours the symptoms entirely disappear. The administration of 3/4 grain of "can- nabinole" in oil (in globules) to a dog weighing about 4 to 6 kilos, is recommended for demonstrating marked symptoms. (For the method of standardization of cannabis indica, see U.S. P., ix, page 605.) One may destroy the cerebrum only in an animal and thus leave the medullary centers intact. This is easiest done in a cat. Normal respiration may go on (no further anesthetic is needed) and the blood-pressure remains high. 206 expekimejSttal pharmacology EXPERIMENT XXX. Heroine or Codeine. (Spinal Bog: Blood-pressure, Lung Volume and Bladder Contractions.) 1. Examine carefully the apparatus shown in Figs. 197 and 198. Arrange a dog (ten or twelve kilos) for record- Fig. 197. — Mercury bulb. ing blood-pressure. The injecting burettes contain heroine (one cubic centimeter equals five milligrams) and adrena- line (1:10,000). Arrange for artificial respiration. Open the abdomen and pick up the bladder. Insert into it at the urachus a glass tube connected with a mercury PRELIMIISTARY OPERATIONS 207 bulb. (See Figs. 198 and 199 for technic and apparatus; also see Experiment XXVIII, page 189.) Use a large bowled tambour to record the bladder contractions. If the bladder is full of urine do not allow more of this to escape than can be avoided. Arrange the mercury bulb as shown in Fig. 199 and fill the bulb about two-thirds full of warm salt solution. Insert the cork which carries a glass tube to connect with the tambour. It is best not to connect the tambour tube until the lung shield is inserted and the dog flercury bulb zso c.c. Salt solution Class or wefal tube qrooved where tied into bladder wall. Abdominal wall Fig. 198. — Arrangement of apparatus for recording bladder contractions. A catheter passed through the urethra may also be used sometimes to connect to the mercury bulb. is pithed, as the bladder tambour and tube would be in the way of the operation. Place a hemostat on the penis or vulva of the animal to prevent urination. By a median longitudinal incision open the thorax (start artificial respiration at once) and expose the right lung and the heart (do not open the pericardium). The anterior mediastinum should, if possible, be gently turned over to the left. Pick vp both phrenic nerves and cut them. Whiff 208 EXPERIMEISTTAL PHARMACOLOGY The lung shield (Fig. 200) should be dipped in warm Avater and inserted in the chest in such a manner that the large notch at the lower border of the shield will just pass over the pedicle and vessels of the right lung. The flanged portion which turns outward at the right hand end of the shield rests on the anterior surface of the diaphragm. There is a groove in the shield between the large notch and the out-turned flange. This groove is for the passage (me- Fig. 199. — The forefinger is placed over the inguinal region just at the lower edge of the abdomen. The beating of the femoral artery should be felt just beneath. An in- cision should be made just over the area. Note the little fold of skin picked up by the forceps while the scissors are used to cut away the skin and fascia. Do not use a scalpel here. The arrangement of the mercury bulb for recording bladder contractions is also shown. sially) of the inferior vena cava. This must not be closed off or the dog will die. Now cut a small hole in the skin of the right side about the position of the anterior border of the sixth intercostal space. Pass an aneurism needle through the muscular wall (through the skin incision) and into the chest. Be sure the 'parietal pleura does not peel ADJUSTMENT OF LUNG SHIELD 209 of and keep the aneurism needle from entering the chest cavity proper. Beside this aneurism needle insert another in the same opening and pnll the sides of the opening thus made far enough apart to insert the bent end of the glass tube sho\^^l in Fig. 201. Be sure the pleura does not close the inner end of the tube. This is the most common source of failure in this experiment. The edge of the lung may also move up when inflated and close the tube. Watch this. With hemostats clamp the glass tube (catching the strings) air-tight in the chest wall. Now close the chest Fig. 200. — Lung shield made of thin sheet brass with a wire rim soldered around the edge to add strength. A little more than one-half natural size. The large notch passes down over the pedicle of the right lung. To the right of the large notch is seen a grooved chapnel for the passage (mesially) of the inferior vena cava. (For method of use see text.) and fasten it air-tight either with hemostats or b}^ sewing. Connect the glass tube to a large bowled recording tam- bour. This records the lung volume changes. The record should be about titw to three inches high. The adjustable by-pass may be opened to allow excess air (which the tam- bour can't hold) to escape. (Air also Avill then enter the by-pass again when the lungs collapse. This exchange is approximately constant, hoAvever, with regular artificial respiration and will not interfere with the validity of the 210 EXPEEIMENTAL PHAEMACOLOGY record.) The animal should be firml}^ tied down to the operating board so the chest cannot move too much. Now pass ligatures through the sides of the neck as de- scribed in Experiment XXIX, page 195 (see also Experi- ment XXVIII, 2, page 192 and Figs. 183 and 184). Isolate the left carotid artery and arrange to inject chloroform (one or two cubic centimeters) into it. Proceed as in Ex- periment XXIX to destroy the animal's brain, but try to Class tube ijb recording tambour Hemost^t clamping string K on corK to chesT^ Adjustable (By-paJJ. Fig. 201. — Arrangement of apparatus for recording the volume changes of the right lung by use of the lung shield. The glass tube shown in the upper part of the illustra- tion, has its bent end passed into the chest cavity. do this by injecting the chloroform into the left carotid artery alone. If you succeed Avell in this you can avoid dissecting out the right vertebral artery. The blood-pres- sure should come down at least to a height of one or one and one-half inches above the base line as seen on the drum. If the pressure does not fall, or even goes up higher, the injection has not succeeded. A very high pressure thus ACTIOX OF OPIUM ALKALOIDS 2.11 produced may last for some time and is very liable to cause the lieart to stop (possibly from the extra strain). The re- spiratory movements of the dog should stop entirely. If they do not, wait a little while and make a second chloro- form injection. Sometimes the diaphragm will contract at every beat of the heart. This is due to an action cur- rent generated by the lieart Avhere the phrenics pass over it. These nerves should therefore be cut heUveen the heart and the diaphragm (while the chest is open). The animal should now lie cpiietly and the blood-pressure should be about one inch or a little less above the base line on the drum. Just above the blood-pressure should be the lung volume record (about two or three inches in height), and above this about one-fourth inch should be placed the tambour record for the bladder which is now connected up to the mercury bulb. Take about one inch of normal trac- ing. If everything is satisfactory then inject five cubic centimeters of heroine (or codeine) solution. Is there any change in the bladder f If not it may have been completely empty and contracted before the drug was injected.- Do you get any lung volume change! How do you account for this? What mechanical factors are involved? How does positive artificial respiration differ from natural res- piration ? As soon as you get a well marked action from the drug injected, then run into the vein one cubic centi- meter of adrenaline. How does this affect your record? How do you account for this ? Of what clinical use might this be? AVhat effect does this have on the bladder? How do you explain this? Wait until the records return to normal and then inject eight cubic centimeters of the second alkaloid (codeine or heroine, or vice versa, depending on which drug was in- jected the first time). How does this drug affect the blad- der and lungs? The dose is larger than the first one given. How do these doses compare with those given to dogs to narcotize them before operations? Has the first injection 212 EXPEEIMEXTAJL PHAR]MACOLOGT ill -^^^''^SfcU^ ay*ul Cf/tdi destroyed. The tracing v/a^ ~a- ronchioles) and blood-pressure _; .;. Both brain and cord were le rrethol described in Experiment LXX. ACTIOX OF OPIUM .\J.KALOID^ 213 Fig. 203.— Tracing si o-.vi!ig ihe action of codeine and "epinine- on the bladder, bronchioles and blood-pressure in a pithed dog. ""i-uioics 214 EXPERIMENTAL PHARMACOLOGY SlladdM.CcyMa^^^>^. Q^^itoXuj-M. . ■r" r ^-'^ ,iiiJl Fig. 204. -Tracing showing the action of muscarine (and "epinine") in a pithed dog alter the animal had become irresponsive to codeine injections. ACTION OF OPIUM ALKALOIDS 215 p 2. • " a. 5- I 3 n> "• •-t 5'° t" o n> 5 ^ ^ ^ W 3 3 w o ffi; 3 ^ 01 o ^ 2. m n fT a. p o 3 3 3 [3- o d (D H to S-OJ a> 4^ 2L W o* 3 ^ a- 216 EXPERIMEJ^TAL PHARMACOLOGY caused any permanent change in the kings or bladder that you can detect by the results of your second injection? Give more adrenaline to revive the animal. Do you see the reflected effects of the filling and emptying of the heart Glass catheter Metal catheter Fig. 206. — Three kinds of catheters. in your lung tracing?' Stop the artificial respiration for a few seconds and watch for the heart action to affect the lung tracing. Fig. 207. — Dissection showing the position and relation of the organs and struc- tures witliin the lower pelvis (dog). The pubes were sawed apart and the left side of the bone shows at L.S.P. A, probe passed into the urethra, Ur; B, probe passed in the vagina, V; R.S.P., right edge of the (divided) symphasis pubis; V, vulva; F.C., fossa clittoridis; Ci, clittoris; IV. V., vaginal wall; Bl, bladder; R.U., right ureter entering the bladder; R, rectum; Ut, uterus. ACTION" OF STRYCHNINE 217 The animal will probably be very low by this time. If it is still alive and the pressure is high enough inject some other of the opium alkaloids, such as dionine, thel)aine or peronine, and try to counteract this effect by injecting ''epinine" (1:1000 — Burroughs, Wellcome and Company, New York). "Epinine" is nearly related chemically and pharmacologically to adrenaline. 2. After the animal dies, if it is a female, try to pass a catheter (Fig. 206) through the urethra into the bladder. Consult Fig. 207 to do this. A catheter made of a very small glass tube slightly curved at the end is very satis- factory for this purpose. Could you thus pass a catheter in a living animal? Isolate the left kidney (or the spleen) and place it in an oncometer. Place a loop of intestine in an oncometer (see Fig. 157). EXPERIMENT XXXI. Strychnine. (Frog: Action on the Cord.) 1. Pith a frog and attach it to a frog board. Dissect loose the right tendo Achillis and gastrocnemius muscle but do not injure the tissues of the thigh. Cut the tendo Achillis long and drive a carpet tack through the knee joint region (avoid the artery and sciatic nerve) as shoAvn in Fig. 208. The tack gives a firm point of attachment for the gastrocnemius muscle. Then place the frog board in a large clamp and arrange all apparatus as shown in the illustration. The drum should have a fairly rapid speed and the muscle lever should write near the bottom of the drum (leaving enough space below for the time record). With a hypodermic needle inject into the dorsal lymph sac of the frog one cubic centimeter of strychnine sulphate solution (one cubic centimeter equals one-half inilligram). Wait about three minutes for the drug to be absorbed and then start the drum. The frog will soon show a marked 218 EXPERIMENTAL PHARMACOLOGY reaction and it is important to record the first manifesta- tions of this effect. The drum is kept running and pres- ently further results will be obtained. When the first round is completed lower the drum and take a second round. Blow against the frog and note the results. How do the contractions obtained on the first round compare with those of the second? After the two rounds are com- Fig. 208. — Arrangement of frog and apparatus for recording the contractions of the gastrocnemius muscle during convulsions. The animal's brain is destroyed. pleted dissect out the sciatic nerve on the back of the right thigh (see Fig. 47, page 54) and cut the nerve in two. Now stimulate the frog (blow against it) and note the re- sults on your records. What does this show? What can you say regarding the action of strychnine? Pass a soft copper wire down the spinal canal and destroy the cord. ACTION OF STRYCHNINE 219 What effect has this on the convulsions! Can you locate the seat of action of the drug from this experiment? In what other ways might you test out your conclusions ''. jStufO^tti'^^. *> ■>S<,tovu)Lt . Fig. 209. — Tracing showing the action of strychnine on the trog made by tions of the gastrocnemius muscle as arranged in Fig. 308. the coatr; This is the usual method for obtaining graphic records to illustrate the action of convulsant poisons. This action can usually be shown quite well on frogs, and since frogs are cheaper and more easily managed than mammals, they are generally used for this purpose. The cerebrum is destroyed. 220 EXPERIMENTAL PHARMACOLOGY EXPERIMENT XXXII. Strychnine. (Frog: Heart and Vago-sympathetic Nerve.) 1. 3Pitli a frog and destroy the spinal cord with a soft copper wire. Examine the beating of the lymph hearts (see Fig. 66) before and after the cord is destroyed. How is the beat of these affected! Fasten the frog down, ven- tral side upward, and dissect out the vagus nerve (Fig. 60). Arrange to record heart tracings on a m,oderately slow drum (Fig. 63). Take about one inch of normal tracing and then stimulate the vago-sympathetic nerve and record the inhibition and recovery. Take two inches more of the normal record and repeat the stimulation. Lower the drum and start a second round. Drop on to the heart a few drops of strychnine sulphate solution (one cubic centi- meter equals one-half milligram) and after a feAV seconds again stimulate the nerve. Thic stimulation record should be directly above the first inhibition record in the first round on the drum. Appl}^ more drug to the heart and stimulate again. Be sure the stimulating current is not too strong and do not continue its application to the nerve any longer than is absolutely necessary or the nerve (or its endings) may be affected. Apply more drug and then stimulate again. How is the beat of the heart affected? Is the muscle of the heart directly concerned in this 1 "What are the later effects of strychnine on the heart when thus applied? How does strychnine affect the innervation of the frog's heart? EXPERIMENT XXXIII. Strychnine. (Turtle: Heart and Vagus Nerve.) 1. Pith a turtle and fully destroy the cord by pushing a soft copper or iron wire (No. 14 or 16) down the spinal ACTION OF STRYCHNINE ^ 221 canal. Arraiift-e for takino- heart tracings. Dissect out the vagus nerve in the neck (Fig. 70) and record a nor- mal inhibition at two places in the lower round on the drum. Lower the drum and start a second round. Apply strychnine solution (one cubic centimeter equals one milli- Fig. 210. — Gi-eene's method of irrigating the heart. gram) to the heart with a medicine dropper or according to Greene's method (Fig. 210) for irrigating the lieart. Do you notice any inmiediate change in the appearance of the heart beat? Might this be due simply to the fluid moisten- ing the heart muscle (as normal salt solution would do) or 222 EXPERIMENTAL PHARMACOLOGY to temperature changes caused by applying the solution? How could you avoid these possible effects? Stimulate the vagus nerve again and record the results. What do you observe! Apply more drug (the record is made as in Experiment XXXII) and try stimulating the nerve from time to time. Are any changes observed? How do you Fig. 211. — Tracing from the heart of a turtle showing the action of strychnine. At the short bar the vagus trunk was stimulated and stopped the heart for a brief period. Subsequently a solution of strychnine was dropped on the heart (at X). The rate of beat was apparently slightly accelerated. Later (at R.J\S.) the vagus trunk was again stimulated but could not slow or stop the heart. What structures were affected by the drug? account for this? How does this compare with the re- sults obtained by other students? Did the turtle have any convulsions? How do you explain this? EXPERIMENT XXXIV. Strychnine. (Dog: Blood-pressure, Respiration, and Kidney, Spleen or Intestinal Loop.) 1. Arrange a dog for taking blood-pressure, respiration, and an oncometer tracing of either the spleen, left kidney ACTION OF STRYCH2sriNE 2-:>?> or a small loop of the intestine. For the latter record an instrument similar to the one shown in Fig. 212 may be nsed, or the ointment box kidney oncometer (Fig. 157) may be employed. It is necessary not to get too large a loop of intestine into the oncometer. Three inches of the small intestine bent into a small loop is sufficient. It is very desirable to fasten safety-pins through the ends of the loop as shown in Fig. 212 to prevent more of the in- testine from Avorking into the oncometer after the experi- Pin +0 fas-ten loop of InfesHne Openinq to receive loop of intestine Fig. 212. — Glass oncometer for a small loop of the intestine. The safety pins should be passed through the edges of the wall of the intestine to prevent more of the intestine from working into the oncometer or any part of the loop from getting out. About three-fourths natural size. ment has started. This may also be accomplished by scav- ing a stitch through each end of the loop with a needle and' thread and tying the thread in the small holes of the onco- meter. If the gut is allowed to keep craAvling more and more into the instrument as the experiment goes on the records Avill soon be spoiled. When the oncometer is ad- justed then attach the tube for the recording tambour and close the ahdo7nen securely Avith hemostats or stitches. 224 EXPEEIMENTAL PHARMACOLOGY Why is this so important? The injecting bnrettes contain adrenaline and strj^chnine sulphate (one cubic centimeter equals one-half milligram). Adjust all writing points (so they will pass each other) on the drum. Keep the anesthesia moderately deep and as even as possible. The oncometer tracing should be the upper record, the blood-pressure next below, then the res- piration, and at the bottom of the drum should be the base line and time marker. The student (and the instructor) should make careful observations in each experiment to determine about what sized tambour bowls and what mag- nification should be used for each organ from which rec- ords are obtained. This will necessarily vary largely with different types of tambours and must be determined in each laboratory from experience. Take about one inch of satisfactory tracings and then inject one cubic centimeter of strychnine. What is the result? Note the time of day. After the pointers return to normal (which should be in a short time) inject one cubic centimeter of strychnine again. When the records are again back to normal inject one-half cubic centimeter of adrenaline. Do you get satisfactory records? What is the action of small (therapeutic) doses of strychnine on the heart and circulation! Slowly, from time to time, in- ject one cubic centimeter doses of strychnine and allow the animal to lie perfectly quietly. Is there any change in the blood-pressure as the action of the drug comes on slowly! After a time there will be a sudden reaction. Be sure the drum is going and that 3^ou record the result well. Do not give any more drug for a while then and wait for further developments. How is the oncometer record af- fected? How do 3^ou account for this? Be sure you are ready to give artificial respiration if it is needed. Observe carefully the actions of the face and mouth muscles when the animal shows most marked symptoms. What is meant by the expression " risiis sardonicits"? Are there any spe- ACTION OF STRYCHXIXE 225 cial pupillary changes? Do yon get any results resembling a Clieyne-Stokes respiration? Deepen the anesthesia a little and see if you can depress the action of the drug a little. Try touching the animal from time to time or jar the board a little and note the effect. What parts of the central nervous system are mainly atfected? What is the difference between epileptiform, clonic and tonic convul- sions? How do you explain these? How^ long did it take for the action of the drug to come on? Do you get satis- factory oncometer tracings? What mechanical factors are concerned in the production of these? Your apparatus should be carefully arranged so you can hold the stands, etc., do^^Tl firmly on the table to prevent them from being shaken out of place. Fig. 213. — Glass ureteral cannula with rubber tube connection. About one-half natural size. Inject some adrenaline into the vein. How does this affect the animal? Secure records of as many typical convulsions as you can. Many of these will probably be spoiled by movements of the apparatus. Crowd on enough ether to check the convulsions, then open the bladder and insert a cannula (or pass a catheter if you can) and close the abdomen firmly with hemostats. Draw off some urine and test it for reducing substances. A^liat action will strychnine have on the glycogen stores of the body? How is this brought about? What mechanisms are concerned? How is strychnine excreted? Could you get a positive test for it in the urine? How long does the drug remain in the body before it is excreted? What bearing does this have on the treatment of strychnine poisoning? 226 EXPERIMENTAL PHARMACOLOGY Kill the animal by a large dose of the drug. What is the immediate cause of death? If time permits open the abdomen and dissect out both ureters (Fig. 162) and trace their course to the bladder. Could you tie a cannula (Fig. 213) in each ureter and col- lect the urine from each kidney seiDarately? What is the innervation of the ureters'? EXPERIMENT XXXV. Strychnine. (Ether, Morphine, Chloral Hydrate.) (Dog: Blood-pressure, Respiration, Oxygen Consumption, Air Embolism.) 1. Read over carefully the section on oxygen consump- tion given in Experiment XXVITI, page 177. The ap- paratus there used is of a very simple form and will be available in most laboratories. A better but somewhat more complicated form is shown in Fig. 172. This figure shows in addition a special arrangement for measuring the oxygen each time it is run in. If only enough water be placed in the pressure bottle to allow 200 or 300 cubic centimeters (the bottom of the bottle must first be filled up to the level of the spout) to run down into the graduated cylinder at a time, then the measuring of this amount of oxygen before it is run into the pan becomes automatic and can quickly be done each time. If the oxygen tank be opened a little oxygen will be forced through the T-tube into the graduated cylinder. This oxygen is un- der pressure and will drive the water in the cylinder up into the pressure bottle. If it is especially desired for greater accuracy, the bottle can then be lowered to the level of the graduated cylinder to avoid compression of the oxygen Mdiile its volume is being measured, but this is not generally necessary, for the compression of the oxygen in the graduated cylinder by the colunm of water up to the pressure bottle will be the same each time and ACTION OF MORPHINE ON OXYGEN CONSUMPTION ^'11 will thus not cliaiige separate readings on the drum. This automatic measuring of the oxygen saves time and should be done by the student who manages the apparatus on the drum. The measuring device can also be used on the simple apparatus shoAvn for Experiment XXVIII if de- sired. Several very interesting and important actions of cer- tain drugs can be recorded either with the apparatus shown in Fig. 172 or with that illustrated in Fig. 175. Thus the short, rapid, up-and-down movements of the heart lever records the respiration of the animal even more ac- curately than does the stethograph around the body. In addition the actual relative amount of gases passing in and out of the lungs at any given period can be compared. And any general change in the volume of the lung con- tents (contraction or relaxation of the bronchioles) is w^ell shown. For the latter purpose the short respiratory excursions of the- heart lever on the drum should be mag- nified to write about one or one and one-half inches in amplitude. Arrange a medium sized dog for recording blood-pres- sure and respiration. The injecting burettes contain adrenaline and morphine (one cubic centimeter equals five milligrams). Attach the apparatus for recording oxygen consumption and take a normal record. This will involve at least one (and better two or three) complete notches on the oxygen record. Now deepen the ether anes- thesia a little [not too much) and see if this slows down the oxygen consumption. What Avould you expect the ether to do? Now get the animal into a perfectly satis- factory condition and inject three cubic centimeters of mor- phine. How does this affect the oxygen record? Can you determine whether the observed result is due to a central or to a peripheral action of the drug? Are there any evi- dences of bronchial changes! Explain. Inject one cubic 228 EXPERIMENTAL PHARMACOLOGY Fig. 214. — Tracing showing the action of morphine (and adrenaline) on the rate of oxygen consumption, on the bronchioles, respiration and blood-pressure in a dog. At the point marked "bronch. contract." in the upper record it will be seen that the curve actually turns downward for a short distance. This is due to the marked con- traction of the bronchioles forcing a part of the supplemental (or reserve) air out of the lungs. This is probably also reflected on the respiratory tracing by limiting the expan- sion of the chest. Adrenaline counteracts this broncho-constricting action of morphine and the three injections of adrenaline each causes a marked increase in the depth of respiration which lasts approximately during the period that the action of the adrenaline can be seen on the blood-pressure. Experimentally it has been shown by Guber at Zurich that animals poisoned by a minimal fatal dose of morphine recover if they be in- jected with adrenaline. How would you explain the prevention of death (from the morphine) in these cases by adrenaline? ACTION OF STRYCHNINE ON OXYGEN CONSUMPTION 229 centimeter of adrenaline. How does tliis affect the record ? Now give a second dose (three cubic centimeters) of mor- phine and see what effect this has on the rate of oxygen consmiiption. Take three or four notches in the oxygen record to get the prolonged effects of the drug. Now arrange for all the drum space you can command and prepare to record the rate of oxygen consumption after strychnine. It is to he recalled that the CO2 exhaled by the animal may vary quite as much as the rate of oxy- gen consumption for short periods of time. If a consider- able excess of CO2 is excreted it can affect the record somewhat before it is absorbed. Will this mean a pro- longation or a shortening of the oxygen record? Will it add to or subtract from the relative length of time which a given injection of oxygen will last? Consider this point carefully in observing the manner in which strychnine acts on the metabolism. Arrange all writing points and inject one cubic centi- meter of strychnine (one cubic centimeter equals one-half milligram). Wait a little and then repeat the injection (one cubic centimeter). Continue this at brief intervals, recording carefully the rate of oxygen consumption all the time. Be sure the animal cannot shake down your apparatus when the convulsions come on. Continue giv- ing strychnine until convulsions are fully developed. How do these affect the rate of oxygen consumption ? What be- comes of the oxygen taken up by the animal ? What is the respiratory quotient? How is it determined? Examine the pupils during and after a convulsion. What do you observe? Crowd on ether and see if you can stop the convulsions. How does this now affect the oxygen con- sumption! Lighten the anesthesia and empty the strych- nine out of the burette. Fill the burette with chloral hy- drate solution (four per cent) and then just after a con- vulsion inject one cubic centimeter of the solution. How 230 EXPERIMENTAL PHARMACOLOGY does this affect the convulsions, blood-pressure, respiration and oxygen consumption? Inject more chloral from time to time and observe its general action as fully as you can. If the animal is still alive empty the chloral out of the burette, then take the burette out of the clamp and place the upper end of the empty burette in your mouth. Take the bull-dog off the femoral vein and blow some air into the vein. Replace the bull dog and watch the action of the air on the animal. What is meant by air embolism! How may it be produced! How does it act inside the heart chambers! In the vessels! Blow more air into the vein if necessary to kill the animal. What conclu- sions can you draw from this! Caution. — The alimentary canal of the dog contains large numbers of tape worms and their eggs. If these eggs are swallowed by other animals infection may occur. If time permits, dissect out the nerves to the bladder (and uterus if the animal is a female). EXPERIMENT XXXVI. Strychnine. (Student: Reaction Time.) 1. Test the acuteness of hearing of the student who is to act as the subject of the experiment. Do this by allow- ing the student to sit at a table (at complete rest) with his ear or the side of his head against a heavy stand (which must not be moved later). A watch is now moved away from the ear of the subject until the ticking can just be heard (note the position of the watch, i.e., which side is toward the subject). Mark this distance on the table or otherwise and then take the watch back to the point where the ticking just fails to be heard. Mark this point. 2. Now refer to the arrangement of the apparatus shown in Figs. 134 and 137 (also see Experiment XIII, 1, STRYCHNINE AND PIC'ROTOXINE 231 page 144) and record tlie snhjeet's normal reaction time for sight, toncli and sound. • 3. Take two tubes of oil (or water color) paint, one white, the other red (other colors may also be used), and with a brush on a white tile surface (pill tile) make a series of mixtures of white and red varying only the slightest degree in color. Also make several just alike. Number these and let the subject note all those between which he can just distinguish a difference. Eecord these results. 4. Now let the subject take a therapeutic dose of strychnine. Caution. — Strychnine is very poisonous. The average dose is one-sixtieLh of a grain, but many physicians give doses as large as one- thirtieth of a grain. The drug is probably best taken in the form of tablets (one-sixtieth grain) as mistakes are thus less liable to occur regarding the size of the dose. 5. Wait fifteen or twenty minutes (or longer) for the drug to be absorbed and then again test the acuteness of hearing, the reaction time for sight, touch and sound, and the acuteness of color sense with the painted spots on the tile (be sure these have not changed their color or appear- ance by drying — the spots should be thoroughly dry be- fore the subject sees them the iirst time). Has the strych- nine affected any of these reactions! Where did the drug act to do this? Is the reaction in the nature of a stimula- tion or a depression? How does this compare with alco- hol? EXPERIMENT XXXVII. Picrotoxine. (Frog: Action on Medulla and Cord.) 1. Examine the arrangement of the apparatus shown in Fig. 208. Pith a frog {cerehrum only) and arrange it thus for recording contractions of the gastrocnemius mus- cle. Under the skin of the back inject one cubic centi- meter of picrotoxine solution (one cubic centimeter equals 232 EXPERIMENTAL PHARMACOLOGY I I I I ^ ^ I I 1 I - n I Fig. 215. — Tracings from the gastrocnemius muscle of a frog injected with picrotoxine. one-half milligram). Wait about three to five minutes for the drug to be absorbed, then start the drum at a moderate rate of speed. After a short time the frog will begin to manifest certain symptoms. Eecord these (on the lower part of the drum^ — the muscle contraction record should have an amplitude of about one and one-half or two inches) and when the first round of the drum is completed lower it and wait a short Avhile. Then take a second round of contractions on the upper half of the drum. How do the last contractions compare with the first ones obtained? Have you studied any other drug having a similar action ? How do you explain the results'? Note. — A method for destroying (cutting off) the cerebrum while leav- ing the medulla intact is described on page 238. ACTIOiSr OF PICROTOXINE Fig. 216. — Tracings from the gastrocnemius muscle of a frog injected with brucine. EXPERIMENT XXXVIII. Picrotoxine,''' Chloretone. (Dog: Blood-pressure, Respira- tion and Kidney, Spleen or Intestinal Loop Volume.) 1. Dissolve three grams of chloretone in about eight cubic centimeters of absolute alcohol. Then add water until a slight precipitate starts to form. Then add a few drops more of alcohol to dissolve the precipitate. Now observe carefully the method of giving drugs to dogs il- lustrated in Fig. 217. The dog for this dose of chloretone *Picrotoxine is not often used in medicine. 234 EXPERIMENTAL PHAEMACOLOGY should weigh about eight or ten kilograms. Some dogs are considerably more susceptible to the drug than others. One student holds the animal between his knees and reaches forward to grasp the dog around the nose and mouth with both hands firmly. The assistant slips a gag (Fig. 218) into the dog's mouth just behind the eye teeth. Fig. 217. — Method of administering medicine to a dog by means of a stomach tube. The mouth is now held closed and this prevents the dog from biting or dropping out the gag. A second assistant should hold the dog's feet to keep it from scratching. Sometimes the hind feet must be held also. An ordinary soft rubber stomach tube (or one-fourth inch rubber tube with a pointed end) is now passed through the hole in PRELIMINARY OPERATlOXh^ -!^)5 the gag and back into the dog's mouth. Pusli tlie tube into the pharynx and wait a little. The animal will make swallowdng movement and these help to direct the tube into the esophagus. When the tube is safely started it can be readil^^ pushed down into the stomach. Caution. — It not infrequently happens that the tube passes througli the larynx and into the trachea. If the drug be injected into the lungs the animal will die in a few moments. This accident must be carefully avoided by using great caution in getting the tube started far back in the dog's mouth. Also when the drug is given pour a little of the solution into the funnel and wait to see what results this has. Breathing sounds may sometimes be heard by listening at the end of the inserted tube if it is in the lungs but these are un- trustworthy as similar sounds are often heard when the tube is in the stomach. Pii in. Hole Rubber tubing Fig. 218. — Mouth gag for dogs, cats or rabbits. Made of wood. Allow about ten or fifteen minutes for the drug to act. If the stomach was filled with food the result will not be the same as if the stomach was empty. The animal often becomes very lively and playful at first, but soon gets weak and unsteady, especially in the hind limbs. After a time it lies down and becomes drowsy or even unconscious. If the dose was too small give a second small amount after fifteen minutes. If the first dose was large enough {and too marked depression sliotdd he carefully avoided) then give a little ether to bring on complete anesthesia and ar- range the animal for blood-pressure, respiratory and on- cometer (kidney, spleen or intestinal loop) tracings. Iso- late both vagi and place loose ligatures around them. It may be necessary to give small amounts of ether to keep the anesthesia sufficiently deep at least in the beginning 236 EXPERIMENTAL PHARMACOLOGY of the experiment. The injecting burettes contain adrena- lin and picrotoxine (one cubic centimeter equals one-half milligram). When the operations are completed adjust the writing- points on the drum and take a normal record. Stimulate each vagus nerve and get records. How does this affect the respiration and circulation? Now inject one cubic centimeter of picrotoxine and get records of the results. Note the time of day. Inject more picrotoxine from time to time in small doses (one-half or one cubic centimeter) and keep a close watch on the heart action as shown by the amplitude of the manometer tracing and by the rate of heart beat. There should be a slowing of the heart and a fall of pressure. Both of these should be brought on very slowly and cautiously by small repeated doses. (Too large a dose of chloretone weakens the heart con- siderably and must be watched in this experiment. It also depresses the medulla somewhat.) The heart beat should become slow enough after a time to give a pressure trac- ing with an amplitude of about ten or twelve millimeters (one-half inch) to each stroke of the manometer pointer. When this stage is reached lift up both vagi and tie the ligatures tightly. Does this affect the heart? If not quickly cut both vagi centrally to the ligatures. Does this affect the blood-pressure? Does the respiration remain normal? How do you account for any changes observed? Did you get satisfactory records of all these changes? If not why did you fail? Can you do better next time? Now stimulate the central end of one vagus nerve. How does this affect the animal? What nervous paths are con- cerned in this? Stimulate the peripheral end of the nerve and note the effect. Inject more picrotoxine. How does the action here com- pare with that in the frog? Inject some adrenaline. Do you get normal effects from this dose? Is the heart ISOLATIOX OF THE SCIATIC XERVE oo- Z.Jl slowed? How is the respiration affected? Now give sev- eral doses of picrotoxine to kill the animal. What is tlie immediate cause of death so far as you can judge by this experiment ? Fig. 219.-— A dissection showing the position in which an incision should be made for finding the sciatic nerve and placing a ligature around it for stimulation. If time permits dissect out both sciatic nerves from the outer and posterior aspect of each hind limb (see Fig. 219). Ligate these nerves loosely and examine them carefully as 238 EXPERIMENTAL PHARMACOLOGY to size, relations, and the best .way to dissect them out quickly. It is sometimes of much help to dissect out one of these nerves and stimulate it to start up the respiration in an animal that has stopped breathing but in which the blood-pressure remains fairly high. EXPERIMENT XXXIX. Hydrastine. (Frog: Spinal Cord.) 1. With a pair of scissors cut off the front, part of the liead of a frog (including the cerebrum) as shown in Fig. 220. Arrange the animal for recording muscular contrac- tions as shown in Fig. 208. Cut on dotted line, just anterior to optic lobes rr.H Fig. 220. — Method for destroying (removing) the cerebrum but leaving the rest of the brain intact in a frog. Note the position of the section. Under the skin of the back inject one cubic centimeter of hydrastine (sulphate or h3^drochloride) solution (one cubic centimeter equals two milligrams). Wait two or three minutes for absorption to occur and then start the drum at a fairly rapid speed. After a little while there should be a marked reaction. Try to record the first action manifested by the frog. Finish the first round on the drum, then lower the drum and take a second round. How do the reactions shown on the last round compare with those in ACTION OF IFYDRASTINE 239 240 EXPERIMEI^TAL PHARMACOLOGY the first round. How do you explain these effects! Cut the sciatic nerve to the muscle you are using. Is the action of the drug central or peripheral? Stimulate the muscle itself directly a few times with single shocks. What does this show? Left Ant Cav^l vein .night Ant Caval vein Pregancjlionic TTeurCn Postqancjiionic neuron Hook from 'Heart lever vonBezold's Ganglion /«/Ke/,aca.a/ Ijn Auricular septa. /^.^^^^. ^^^^^.^^ ' In suriculo-ventricular junction stimulating electrodes in 3ino-auricular junction [Crescent] Sympathetic fibres^ dotted lines Fig. 222. — Diagram to show the innervation of the heart in the frog or turtle. EXPERIMENT XL. Hydrastine. (Frog: Heart and Vagus Nerve.) 1. Pith a frog and dissect out the vagus nerve (Fig. 60). Arrange to record heart tracings and take one inch of normal record. Stimulate the vagus nerve and get a normal inhibition. Then pour on the heart a few drops of hydrastine sulphate solution (one cubic centimeter equals five milligrams). How does this affect the beat? Stimulate the vagus nerve again and record the result. HYDRASTINE AISTD CAFFEINE 241 What do you observe? How do yon account for this? Drop on some more of the drug and again stimulate the nerve. Is there any change? Now take up the electrodes and (Avliile the drum is going) turn on a strong (tetaniz- ing) current. With the extreme tips of the electrodes just touch for a moment the tissues at the base of the heart just where the sinus venosus joins the right auricle. This is about the point where the inferior vena cava pass- ing forward would bend up toward the right auricle. The inferior (caudal) border of the tissue which forms the connecting tube between the sinus -venosus and the right auricle is called the crescent. AVhat result do you ob- serve following a brief stimulation of this area? (Examine Fig. 222.) EXPERIMENT XLI. Hydrastine. (Turtle: Heart and Vagus Nerve.) 1. Pith a turtle (brain and cord) and take a normal heart tracing showing vagus inhibition in two or three places. Lower the drum and start a second round of the tracing. Drop some hydrastine solution (one cubic centi- meter equals five milligrams) on the heart. Eecord the re- sults and then stimulate the vagus nerve again. What do you observe? Apply more drug and stimulate again. Now stimulate the crescent and note the results. What do you observe? Can you explain this? EXPERIMENT XLII. Caffeine. (Frog: Central Nervous System, Muscles.) 1. Cut off the front part of the head of a frog (Fig. 220) and inject two cubic centimeters of caffeine solution (the free drug, not a salt, is preferable — use a saturated solution in warm water) into the anterior lymph sac (Fig. 242 EXPERIMENTAL PHARMACOLOGY ACTION OF CArFElNE 243 66). Place the frog in a battery jar and examine it from minute to minute. Do you note any immediate symptoms! Touch the muscles of the hind legs from time to time and note any changes. Does the animal have convulsions? If so, of what character are they? Keep the animal under observation until it dies, watching the muscles carefully. Do you observe any changes in these? If so, what explana- tion can you offer? EXPERIMENT XLIII. Caffeine. (Frog": Muscle and Nerve.) 1. Pith a frog and isolate both gastrocnemius muscles and both sciatic nerves (attached to the muscles, i.e., nerve muscle preparations). Determine the normal minimal stimulation to cause contraction in nerve A and muscle B. Pour a small amount of caffeine solution into each of two watch glasses. Into watch glass A place the nerve of one of the muscle nerve preparations and into watch glass B place the muscle of the second preparation. From moment to moment stimulate the nerve of iDrejDara- tion A and the muscle of preparation B with single shocks. What action has caffeine on the vitality of nerve trunks and of muscle ? Which is affected first ? Watch the mus- cle closely and note any gross changes in appearance, color, length, solidity, etc. What do you observe? What ex- planation can you offer? Tease out some small fibers from muscle A and place them on a slide and examine with a compound microscope. Can you see the cross striations well? Cover the fibers with a cover glass and while watch- ing the fibrils closel}^ run a few drops of caffeine solution under the edge of the cover glass in such a manner that the solution reaches the fibrils you are watching. What effect has this on the muscle fibers? How are the cross and longitudinal markings affected? How do you ex- plain this? o 244 p:xperimei^tal pharmacology EXPERIMENT XLIV. Caffeine. (Frog: Heart and Vagus Nerve.) 1. Take a normal heart tracing from a pithed fro (showing vagus and crescent inhibition). Drop caffeine (saturated solution) on the heart and record the effects. Stimulate the vagus nerve and note the action of the drug on the inhibitory nervous mechanisms. Apply more drug and again stimulate. Stimulate the crescent also and see if it is affected. Take several rounds of the tracing on the drum to get a good insight into the action of the drug on the heart muscle. How does this compare with the action on the mammalian heart? EXPERIMENT XLV. Caffeine. (Turtle: Heart and Vagus Nerve.) 1. Repeat the previous exj^eriment on a pithed turtle. Can you see any changes in the tone of the heart muscle as indicated in your records? EXPERIMENT XL VI. Caffeine. (Man: Reaction Time.) 1. As in Experiment XXXVI (and XIII) determine the normal reaction time of a student. Then allow the stu- dent to drink one or two cups of strong tea or coffee (or take three grains of caffeine powder in capsules) and at intervals of one-half, one hour and one and one-half hours later again take the student's reaction time. What do you observe ? How do you explain your results ? On what parts of the central nervous system has the caffeine acted to produce the results observed? ACTION OF CAFFEliS^E 245 EXPERIMENT XLVII. Caffeine. (Frog: Muscular Work.) 1. Pitli a frog and ligate the riglit thigh tightly so as to shut off the circulation. Fasten the animal down on a Very fine copper wires, aif ached to tack and to tendo Achillis Fig-. 224. — Arrangement of a frog and apparatus for recording "fatigue tracings" from the gastrocnemius muscle. The drum should have a slow speed. (For descrip- tion see text.) board as shown in Fig. 224. Isolate the tendo Achillis of the right leg and arrange as illustrated for stimulating with single shocks. The primary current is best inter- rupted by a metronome as illustrated, but if this is not 246 EXPERIMENTAL PHARMACOLOGY availalble then a student can interrupt the primary cur- rent with a simj)le key hy hand (once in one or two sec- onds). The drum must have a slow speed. The second- ary shocks are carried directly to the muscle by very fine copper wires one of wdiich is attached to the carpet tack which is driven through the frog's right knee into the frog board to hold the upper end of the gastrocnemius muscle firmly in place when the muscle contracts. The other wire is tied to the tendo Achillis. Now inject into the dorsal lymph sac one cubic centimeter of five-tenths per cent caf- n c: ''lllllll'^*' Hubber tube wire Cannula wfh points for cats a rabbits Point for docjs Fig. 225. — A method for making cannulas with separable points. One end of the "T" of a • glass (5/16 inch) T-tube is cut off short and short glass points are attached by means of a piece of rubber tubing. It is vastly easier to make the small points than to blow a T-tube and to make a cannula entirely of glass. (The points illustrated are larger than they should be for rabbits and cats.) feine solution (Greene) and allow this to be absorbed while the experiment is going on. When all adjustments are made start the drum and record a normal ''fatigue curve" from the right gastroc- nemius. (For a description of fatigue curves see any manual on experimental physiology.) This curve should be taken on the low^er half of the drum. CAFFEINE DICRESIS 247 AVlien tlie muscle is exhausted then ligate the left thigli tightly and drive a second carpet tack through the left knee to hold tlie left gastrocnemius firmly. Isolate the left tendo Aehillis. Disconnect the stimulating wires, re- move the frog board from the large clamp and turn the frog board around on a perpendicular axis so that the frog will be on the side away from the apparatus. Also remove the large clamp, turn it over on a horizontal axis and re- attach it to the stand. Keplace the frog* board. The left leg of the frog will now occupy practically the same position that the right leg formerly had. Attach the stimulating wires and connect the tendon to the muscle lever. The load, magnification, tension, etc., of this muscle must be the same as that used with the right muscle. About twenty minutes should now have elapsed for absorjition of the caffeine. Start at the beginning of the uj^per half of the drum and record a fatigue curve of this muscle, which will now show the effect which caffeine has on muscular work. The rate of stimulation should not vary (once in one or two seconds) for each curve. How does the normal fatigue curve compare with the caffeine curve! What conclusions can you draw! EXPERIMENT XL VIII. Caffeine. (Rabbit: Diuresis, Cervical Nerves, Depressor.) 1. Dissolve two grams of urethane in about twenty-five cubic centimeters of water. Select a full grown rabbit and with a catheter used as a stomach tube inject the urethane into the rabbit's stomach. [Pass the tube through the hole in a wood gag (Fig. 218) held in the animal's mouth.] AVait about ten or fifteen minutes for the di'ug to be absorbed and then give the animal a little ether to bring on complete anesthesia. Use great care in this for rabbits die verij readUij. Insert a tracheal can- 248 EXPEEIMEl^TAL PHARMACOLOGY nula (one-fourth inch diameter) and connect up the ether bottle (or anesthetic device shown in Fig. 116). Use the greatest care in giving the ether not to kill the animal. In- to the femoral vein tie a very small injecting cannula (Fig. 18) connected to a burette containing caffeine solution (.5%). Record the respiration on the drum. Open the abdomen over the bladder and insert a bladder cammla (Fig. 23). Arrange the cannula to empty into a graduated cylinder and when all preparations are made wait ten or twenty minutes to record the nonnal rate of urine secretion. Test this with Fehling's solution. Then cautiously inject one-half cubic centimeter of caffeine so- lution into the vein. Watch the effects of this on the respiration closely. From time to time as the animal will Sliding^ rubber tube I ilWiiW^VllWWUWVmW ^ ^ v\/ashour Fig. 227. — An easily made glass cannula showing a sliding rubber tube which may be used to open or close the small opening blown in the side of the tube and used as a "washout." tolerate it inject more caffeine in one-half cubic centimeter (or smaller) doses. Is there any change in the rate of urine flow? Collect the urine for each ten minute inter- val. Test for reducing bodies again. Is sugar present! If so, how do you account for it! If you have time, consult Fig. 226 to learn the ar- rangement of the vagus, sympathetic and depressor nerves in the neck of the rabbit, and then carefully dissect out these nerves. Using a very small arterial cannula (Figs. 225 and 227) connect the right carotid artery to the ma- nometer and take a blood-pressure tracing. Stimulate the depressor nerve (peripherally) and note the effect. How do you explain this result! Inject more caffeine and see if CAFFEINE AXD SODIUM SUI-PHATE 249 you can obtain any idea of the action of tJie drug on the heart and circulation. Kill the animal with a large dose of caffeine. After the animal is dead dissect out the vagus, sympathetic and depressor nerves in the other side of the neck, EXPERIMENT XLIX. Caffeine, Sodium Sulphate. (Dog: Blood-pressure Diuresis, Respiration, Sciatic Nerve.) 1. Dissolve three or four grams of chloral hydrate in a little water and inject the solution into the rectum of a medium sized dog. See that the solution does not run out again immediately after injection. In ten minutes anesthetize the animal fully with ether (or etherize the animal at the start and omit the chloral or give it by stom- ach — it is advisable to give the chloral, how^ever). Ar- range to record blood-pressure, respiration and the rate of urine flow. Place caffeine (.5%) and adrenaline in the in- jecting burettes. Open the abdomen and lift up the bladder. At the pos- terior side of the base of the bladder you w^ill find the ureters entering the bladder from each side (see Fig. 162). Pick up the ureters and place in each a ureteral cannula (Fig. 213) and arrange to record the rate of urine secre- tion by obtaining a record on the drum of the drops fall- ing from the cannulas. To do this arrange two tambours as shoA\Ti in Fig. 228 in such a manner that each drop of urine falls on a small metal disc attached with wax (colo- phonium or ceiling wax) to the writing point of the first tambour. The second connected tambour records these drops on the drum. Consult Fig. 219 and dissect out the sciatic nerve in one hind limb. While recording blood-j^ressure and respira- tion stimulate the nerve with a medium strength Faradiz- ing current. What do you observe I Can vou think of a 250 EXPERIMENTAL PHARMACOLOGY condition in which this procedure might be of help in re- viving an animal I Try this on the next animal you have in which the respiration ceases, especially if the blood-pres- sure remains fairly high. Adjust all writing points, allow the animal to return to normal (keeping the anesthesia as regular as possible) and Drop: Metal plate Fig. 228. — Arrangement of two tambours to form a drop recorder. wait ten or twenty minutes to record the normal rate of urine floiv. When this is obtained (not a drop of urine may have been secreted during this jDeriod, in which case simply watch for the flow to start up) then proceed to give the caffeine. AVatch for the effect on respiration and the circulation. Inject one cubic centimeter of caffeine.. What do 3^ou observe? Increase the dose if the animal will ACTION OF SODIUM SULPHATE 251 >'H. 252 . EXPERIMENTAL PHARMACOLOGY stand it and continue giving the drug until several centi- meters are injected. Wait a while to observe the effect on urine flow. This often fails in dogs. Why? Will tlie chloral influence the result in any Avay? Wait for fifteen or twenty minutes for the caffeine to act. Be sure the dose given was large enough. Then al- low the animal to become as nearly normal as possible and get a new normal rate of urine flow. Test the urine for sugar. What do you observe? Explain. Now empty the caffeine out of the burette and fill it with four per cent sodium sulphate solution. Inject one cubic centimeter. Increase the dose rapidly (twenty cubic cen- timeters or more may be given at a time often without killing the animal) and Avatch the effect on blood-pres- sure, respiration and urine flow. What do you observe? How does this compare with the action of caffeine? If the animal is still in fair condition substitute a four per cent solution of sodium phosphate (or nitrate or chloride) for the sodium sulphate and inject a considerable quantity of this salt. How is the rate of urine flow affected ? What theories of urine secretion do you knoAV? On the basis of these explain the action of the drugs injected. Keep a record of the amount of solution injected in each ten min- ute interval and see if you can collect an equal volume of urine in a beaker in the same time. This can sometimes be done, especially with rabbits. Kill the animal by a large injection of one of the salts mentioned (watching the urine flow as the drug is acting), then dissect out the pan- creas and see if you can find its lower duct (Figs. 2-1:4 and 245). Could you put a cannula in the duct while the ani- mal was alive? Dissect out the gall bladder, the cystic duct, and the common duct. What are the relations of the pancreatic ducts and the bile ducts as the^^ pass through the wall of the intestine? DIURETINE AISTD AGUKTXE 253 EXPERIMENT L. Diuretine, (Sodium-theobromine-salicylate), Agurine, (Sodium-theobromine-acetate). (Rabbit: Diuresis and Respiration.) 1. Give by stomach two grams of urethane dissolved in twenty-five cubic centimeters of water to a good sized rab- bit. Wait ten minutes for the drug to be absorbed and then give the animal a little ether to complete the anes- thesia. Arrange to record (or collect or both) the drojDS of urine as they fall from a bladder cannula (or from two ureteral cannulas). Place a cannula in the femoral (or jugular) vein and connect up a burette. Fill this with diuretine one per cent (or agurine, one per cent). Arrange to record the respiration. Count the pulse rate per minute. When all preparations are made wait ten or twenty min- utes to obtain the normal rate of urine flow. Then inject one-half cubic centimeter of diuretine [(Ivnoll and Com- pany, 45 John St., New York) or agurine] and record the effect on the respiration. Count the pulse rate and see if it is affected. Now give more of the drug from time to time and try to bring on the effect gradually, Avatching carefully not to kill the animal by an overdose. What do you observe 1 How do you account for this? If your drop recorder does not work well then let a student operate the recording signal magnet by means of a simple hand key placed in series with a dry cell and the signal magnet. The student can make and break the current each time a drop falls. If you are slvillful enough you can make a de- vice to record each drop by electrical contact. But do not spend too much time at this. When you have obtained as marked results as possible from the diuretine (or agurine or both) then if the rabbit is still in suitable condition fill the burette with one of the following solutions: 254 EXPERIMENTAL PHARMACOLOGY 2% sodium nitrate, 2% sodium i3liospliate, 2% sodium chloride, 2% ammonium chloride, 2% ammonium acetate. Arrange to observe the full action on urine secretion and cautiously inject one-half cubic centimeter (or less) of the solution in the burette. AVitli great care gradually inject more of the solution from time to time as rapidly as the animal can tolerate it. What effect has this on the urine flow? Continue the administration as long as satisfactory results can be obtained. EXPERIMENT LI. Urea, S. A. Matthews' Solution, or Saline Diuretics. (Rabbit or Cat: Diuresis.) 1. Repeat the above experiment with a rabbit or cat (us- ing two grams of urethane for an average sized animal, or 1.7 cubic centimeters per kilogram of paraldehyde for a rabbit — Edmunds) but after securing the normal rate of urine flow begin to inject one of the following: A. Urea (5% solution). B. S. A. MaUheiv's solution: NaCl, 3.67 grams. Na2S04, 10.1 grams. Sodium Citrate, 3.36 grams. CaCl2, 0.136 grams. Water, 1000 c.c. C. Three per cent solution of any of the following: Sodium sulphate. Sodium phosphate. Sodium nitrate. Ammonium nitrate. ACTION OF CURARA 255 Sodium chloride. Sodium iodide. Use great care in making the injections. Begin with very small doses and inject more as the animal is able to tolerate it. What conclusions can you draw with reference to the diuretic action of these substances? How do they act! EXPERIMENT LII. Curara. (Frog: General Action, Claud Bernard's Experiment.) 1. Pith a frog (cerebrum onh^) and make a small incision over the back of the right thigh (see Fig. 47). Dissect up a short length of the sciatic nerve. Do not cut or injure the nerve. Pass a thread beneath the nerve and tie off the tis- sues of the thigh tightly so as to completely stop all circula- tion in the right (gastrocnemius) muscle and foot. AVith single shocks stimulate the exposed nerve once or twice to see hoAV the muscles act in the isolated part of the leg. Also stimulate the tissues at the back of the head over the upper end of the cord once or twice to get the normal reactions. Put a drop of acetic acid on the left hind foot and see if the animal moves the liml). Brush off the acid. Count the rate of l3anph heart beats. Into the ventral l3mipli sac inject one cubic centimeter of a saturated solution of curara. Wait three minutes and then begin to retest the reflexes from time to time as the drug is absorbed. How is the rate of beat of the lymph hearts affected? Will the animal jump when stimulated? As the action of the drug becomes very marked stimulate again the exposed sciatic nerve. (Keep the nerve moist "\AT.th salt solution where it is exposed.) Apply a drop of acetic acid to the skin of the back. Is there any response ? If so, Avhere ? Stimulate the upper end of the cord. What muscles 256 EXPEKIMENTAL PHARMACOLOGY respond! Stimulate the left gastrocnemius (through the skin) directly. Does it contract? What conclusions can you draw? Where does curara act? Does your experiment prove the nerve trunks are not paralyzed ? Are the sensory nerve endings paralyzed? Does your experiment give you a chance to test this point? Count the l3anph heart rate Fig. 230. — Tracing showing the action of a solution of curara dropped on the heart of a frog. Lower line normal, showing the inhibition caused by stimulation of the vagus trunk. Second line, curara was applied at "x" and the vagus was again stimulated as shown by the short line and legend. Third line, the application of the drug was con- tinued and the vagus trunk was again stimulated as indicated. No noticeable results fol- low the stimulation. Why not? Fourth and fifth lines, application of the drug was con- tinued and its action on the heart is shown. again. What conclusions can you draw from this ? What is the action of curara on the central nervous system? (See McGuigan: Journal of Pharmacology and Experimental Therapeutics, 1916, viii, p. 471.) Do you knoAv of any other substances possessing an ac- tion on motor nerve endings in striated muscles like curara does ? How does this drug differ from atropine in its action on nerve endings? Cenfer for ^ ,^^, --,^,/.. cranial secretprKf/b^^w Facial nerv^iiN.VII Cerebellum, ^ Giossophdrynqeal/^nerve^ Medulla oblongata Parotid gland Cord- .^/v,. Center for --I'l) "////^^)/asodilator ner'^'s '''f.yf^^/M///'/opi\c ganglion ^ner^i^^P^^""'""^'" ^'^^^^^^'^^ ) ganglion (n \/)^^^^°''^^ '^y'^P^^' nerve i^/V. V l^m^i^fjjgii superficial '" petrosal nerve Pon^^>J^'^^lnf max. div. N. V Q^'xr' J acobson's \^ nerve tympani branches/ Parotid duct (5ten son's) Submaxillary duct {Wharton's} ■Sublingual duct {Bartholin's) Lingual nerve Chordo-lingual triangle t. Electrodes ( Large amount of thin saliva, vasodilatation ^Sublingual gland '^Superior cervical gang. 'Submaxillary Electrodes^ aland ^{5mall amount of thick saliva vaso- constriction ) Waso constrictor fibers sympathetic secretory fibers ^Outgoing sympathetic rami communicantes Post- ganglionic fibers are dotted thus — Fig. 231. — Diagrammatic representation nf the innervation of the salivary glands m the" dog. ACTION OF CURARA 257 EXPEKIMENT LIII. Curara. (Frog: Heart and Vago-sympathetic Nerve.) 1. Pith a frog and arrange to take a heart tracing. Stimulate the vagus nerve and get a normal inhibition. Drop on the heart a few drops of a saturated curara solu- tion. What do you observe? Now stimulate the nerve again and record the result. Has any change been pro- duced! If not apply more curara and stimulate again. Now stimulate the crescent and record the result. A^Tiat do you observe? How do you explain this? Apply more of the drug to bring out the later action on the heart. EXPERIMENT LIV. Curara. (Turtle: Heart and Vagus Nerve.) 1. Repeat the above experiment on a pithed turtle. How do the results obtained with this animal conijoare with those from the frog? "What is the innervation of the tur- tle's heart? How does it differ from that of the frog? EXPERIMENT LV. Curara, Strychnine. (Dog or Cat: Blood-pressure, Respi- ration, Urine, Sciatic Nerve. Dog: Salivary Ducts and Nerves.) 1. Weigh a medium-sized dog and give it by stomach three hundred milligrams of chloretone per kilo of body weight. Dissolve the chloretone in ten cubic centimeters of alcohol (absolute) and dilute the solution as much as pos- sible with water. Add a little alcohol to redissolve any pre- cipitate formed. After ten minutes etherize the animal and attach it to the operating l^oard. Arrange to record blood- pressure and respiration (stethograph). The injecting bu- 258 EXPEKIMENTAL PHARMACOLOGY rettes contain strychnine (one cubic centimeter equals one- lialf milligram) and adrenaline. (If a cat must be used give it two grams of urethane in twenty-five cubic centimeters of water by stomach, or give 1.7 cubic centimeters of paral- dehyde per kilogram of animal — Edmunds.) Insert a bladder cannula into the fundus of the dog's bladder, draw off a little urine and test it with Fehling's solution. Do you get a reduction! If so how do you explain it ? Now consult Fig. 219 and dissect out the sciatic nerve using great care not to disturh the vessels of the leg. (These are carefully avoided so the curara can be well distributed to the muscles innervated by the sciatic.) Stimulate the sciatic with a medium strength Faradizing current and note the effect on resjDiration and blood-pressure and on the muscles of the leg below the point of stimulation. Beneath the skin of the back or side inject mth a hypo- dermic syringe twenty cubic centimeters of a saturated solu- tion of curara (Merck's). This dose is exceedingly large if the drug is pure, but it is usually impossible to get a first- class preparation of the substance in this country. Note the time of day and observe how long a time is required for the drug to act (slow or weaken or stop the respiration). How is the blood-pressure affected? (It may be necessary to give more of the drug later.) Be on the watch for the respiration to become shallow. How does this aifect the blood-pressure! Be sure to keep the anesthesia going if the dose of chloretone was not sufficient to completely main- tain the narcosis. This drug is supposed not to prevent sensation, hence the animal must be kept anesthetized. As the respiration begins to fail give artificial respiration. This must be maintained during the remainder of the ex- periment. From time to time briefly stimulate the vagus nerve with a medium tetanizing current and note the effect on the heart. Do you observe any change after the action of the drug has become very marked! Is there any change in ACTION" OF CURAKA 259 the reaction of the pupil when the vago-sympathetic trunk is stimulated? Collect a few drops of urine and test with Fehling's solu- tion. Is there any reduction? How do you account for it? Pick up the sciatic and stimulate it again with the same strength of current as that used the first time. Do you get a response? What conclusions can you draw? How does electrical stimulation compare mth the natural nervous im- pulse ? NoAv get the animal in as good condition as possible and while recording the blood-pressure inject one cubic centi- meter of strychnine. Follow this up rapidly mth more injections as fast as the animal can well tolerate the drug. Watch for con\'Tilsions. Do you get these? What muscles are atfected by curara? What ones are not affected? Does the action of strychnine extend to any of those not affected by curara? If so Avhat manifestations of this action would you expect? Are these present? Is there any change in blood-pressure? If so how long is this change present as compared mth the action of strychnine in a noncurarized animal? Explain this. Stimulate the vagus and sciatic uprves again and note the results on the heart and leg mus- cles. Is there any change in blood-pressure when the sciatic is stimulated? If so how does this compare Avith your nor- mal record? What structures are involved and how are they affected (Bayliss: Journal of Physiology, Ixxx, 353)? Dog.— Consult Figs. 237, 238, 239 and 240 and dissect out the submaxillar}^ and sublingual ducts. Also dissect out the chorda t^mipani nerve. For the general distribution of nerves to the salivary glands see Fig. 231. If the ainmal is still in suitable condition try to insert a cannula (Fig. 102) into Wharton's duct as indicated in Figs. 238, 239, and 21:0. Stimulate the chorda tympani nerve and see if you can ob- serve any effects on the rate of salivary secretion. AMiat action has curara on the salivary apparatus? Have you demonstrated this? Kill the animal with a large dose of 260 EXPERIMENTAL PHARMACOLOGY strychnine. After death dissect out the ducts and chorda tympani nerve on the opposite side. Can you easily dif- ferentiate between the two ducts? Can you locate the chordo-lingual triangle? Cut out (label) both eyes and place them in thirty per cent alcohol. Save for dissection later. EXPERIMENT LVI. Coniine. (Frog^: Heart and Vagus Nerve.) 1. Pith a frog, arrange for taking a heart tracing and stimulate both the vagus trunk and the crescent. Get rec- ords showing the inhibition from each of these. Drop two or three drops of a one per cent coniine solution on the heart. How does this affect the record? Now stimulate the vagus and crescent again and record the results. "What do you observe 1 How do you explain this ! A¥hat other struc- tures are similarly affected by coniine ? Make a diagram of the innervation of the heart (Fig. 222) of the frog in your permanent note book and indicate on it the structures af- fected by coniine and state the nature of this action. Apply sufficient coniine to the heart to bring it to a standstill. Do you know of any other drugs that act lilve coniine ? "Watch for these later. EXPERIMENT LVII. Coniine. (Turtle: Heart and Vagus Nerve, Lungs and Sympathetic Nerves.) 1. Repeat Experiment LVI on a turtle and secure rec- ords to show the action of the drug. After a record show- ing the specific action of the drug on the ganglia has been obtained (how would 3^ou prove this?) then unhook the heart lever and remove the turtle from the drum. (It is often advisable to use a fresh turtle for this part of the ex- periment. Large turtles are preferred.) Consult Pig, 232 To tambour Hook Leg done (cun Fllunq parhally inflated . bronchus Leg bone (cut) Heart L lung partially inflated Position occupied by hind limbs (removed) Fig. 232. — A turtle with the Ijrain and spinal cord destroyed and with the plastron and most of the viscera, limbs and skeletal muscles removed to expose freely the partially inflated lungs._ A bull-dog is placed on the right bronchus to exclude the right lung from communication with the recording tambour which is connected with the left lung by means of the glass cannula tied in the trachea. The electrodes are shown placed under the left vagus trunk. The heart beats freely. Stimulation of the vagus nerve causes a marked contraction of the corresponding lung. (See Fig. 233 for arrangement of the recording apparatus.) 262 EXPERIMENTAL PHARMACOLOGY and note carefully what has been removed. Cut the plas- tron loose at each side and remove it. Lift up the intestines and liver and with great care dissect them loose from the lungs. To do this put a cannula (Fig. 233) into the trachea and attach a rubber tube. Then mth the mouth blow the lungs up as indicated in the illustration and clamp off the rubber tube. This holds the lungs partially distended and .--■ /y^/'<*<-i Fig. 233. — Arrangement of apparatus with a turtle held in a Higgin's turtle frame (of 3/8 inch iron rod with hooks at the corners to which the limbs are tied) for record- ing lung contractions. A very sensitive large-bowled tambour with a large magnification is used, and the lungs are partially inflated by forcing a little air (with the mouth) into the side outlet of the tubing. This puts the tambour and the lung both under moderate tension and in direct communication. When the lung contracts the tambour pointer rises but when the lung relaxes the pointer descends as the rubber membrane on the tambour forces the air back into the lung. Drugs are conveniently administered by in- jection into the heart with a fine pointed hypodermic syringe. greatly aids in the dissection. Use great care not to punc- ture the lungs. If you do this, find the hole, lift up the edges of the opening and tie a ligature around the puncture. TURTLE LUNC TEACIjNT'G 263 When the entrails are removed \ len cut out all tlie skeletal muscles you can including the entire hind limbs and most of the muscles of the fore limhs. This exposes the lungs prac- tically free from skeletal muscles. Connect the tracheal cannula with a tambour (very sensi- tive, medium-sized bowl) and bring the writing point on to a slow drum. Observe the way the bull-dog is placed in the ^tuyy^. Fig. 234. — Tracing showing the contraction of the left lung of a turtle when the left vagus nerve was stimulated electrically. figure. In a similar manner clamp off one bronchus and then pick up the main trunks of the vagus and s>anpathetic nerves on the opposite side well up in the neck. See that the lung is partially inflated and the tambour under a slight tension. Start the drum, and with a fairly strong tetaniz- ing current stimulate the vagus and sympathetic trunks 264 EXPERIMENT/ -L PHARMACOLOGY (see Fig. 234). What do you observe? What are your con- clusions? Consult your text-book on physiology for further explanation regarding the innervation of the lungs. Now ^ fi'htJiXU%,'tJUU)Jtl^ iKiiimiiiiiiiinniiiiiiimiiiissiiiiiiiiiimiiimiiiimiiiri Fig. 235. — Lung and heart tracings from a turtle showing the effect of electrical stimulation of the right vagus nerve (first contraction and inhibition) and of mechanical stimulation (tearing) of the same nerve (second and third records). make a careful dissection of the nerves (and sympathetic branches) on the opposite side of the neck. Make a sketch of these nerves for future reference. It is exceedingly desirable in making the preliminary dis- section to remove as much as possible of the skeletal mus- culature. This prevents movements which may be confused with the lung contractions. ACTION OF CONIINE 265 Fig. 236. — Diagrammatic representation of the innervation of the lachrymal glands. EXPERIMENT LVIII. Coniine. (Dog: Blood-pressure, Respiration, Salivary- Glands and Kidney, Spleen or Intestinal Loop.) 1. In the usual manner j)repare a dog (ten or twelve kilos) for recording blood-pressure and respiration. The animal may be given morphine, twenty milligrams (one cubic centimeter of two per cent solution) per kilogram of body weight half an hour before the operation, or ether alone may be used. The injecting burettes contain coniine 266 EXPERIMEl^TAL PHARMACOLOGY (one per cent) and adrenaline. (Poor samples of coniine are frequently obtained.) Isolate and ligate loosely .both vago-syinpathetic nerves. Consult Figs. 237, 238, 239, and 240, and dissect out Whar- ton's duct. Place a cannula {very small) in the duct and fasten it with a ligature (thread). Dissect out the chorda tympani nerve and when you can see it clearl}^ lying across the tip of the sublingual gland then place the ends of the Fig. 237. — A dissection showing the position and extent of the first incision for ex- posing the chorda tympani nerve and the ducts from the submaxillary and sublingual glands. electrodes on the nerve and stimulate it. Do you get a nor- mal result? If not why did you fail! (Dissect out the op- posite duct and nerve if necessary.) Consult Fig. 231 for the general distribution of nerves to the gland. Are any other glands thus innervated? If so what ones? Open the abdomen and place an oncometer on a kidney (left), spleen or an intestinal loop. Close the abdomen with hemostats and arrange all writing points in the following Angle of jaw Trachea Fig. 238. — Dissection showing the position and relation of the hypoglossal and lingual nerves (dotted and colored yellow) beneath the thin, band-like mylohyoid muscle which is to be torn across with a blunt probe (tiot with a scalpel) to expose the nerves (and ducts) beneath. Torn edqe of mylohyoid muscle Diqaslric muscle Vein," in fascid Sublingual duct ( Bartholin's) Submaxillary duct (Whartons) Lingual nerve Mylohyoid muscle displaced mesially Hypoglossal nerve Fig. 239. — The mylohyoid fibers have been torn across and the two ducts and the lingual and hypoglossal nerves are exposed. Fig. 240. — Exposure of the chorda tympani nerve, Wharton's duct and Bartholin's duct. Method of procedure for inserting a cannula into Wharton's duct. I ACTION OF CONIINE 267 order from above do^ai, oncometer, blood-pressure, respira- tion, base line and time signal. Take a normal record, in- cluding a vagus stimulation, and then inject one cubic centi- meter of coniine solution. Watch the pupils as the drug is injected. Do you obtain satisfactory^ results? How did the heart beats appear just after the drug was injected? How do you account for this ? Stimulate the vagus nerve again and record the result. Has any more saliva been secreted ? How do you account for any changes in the oncometer trac- ing. Inject a small dose of adrenaline to see if your appa- ratus, etc., is working satisfactorily. Inject a second dose of coniine. This may be larger or smaller than the first dose depending on the reactions brought about by previous injections. Do you get a fall in blood-pressure? If so how do you explain it? If you get a rise what is the cause of this? Stimulate the vagus again and explain its action on the heart. Observe the corre- sponding pupil while the nerve is stimulated. Stimulate the chorda and see if any change has been produced in it as shown by the salivary secretion. Explain any changes ob- served. From time to time give more coniine as the animal Avill tolerate it. Be ready to apply artificial respiration if necessary. At intervals stimulate the vagi and chorda and if a response fails to be obtained explain its cause. Then follow the course of the chorda tympani back under the jaw bone as far as you can (do not injure the duct) and finally push the electrodes far down into the hilus of the gland and stimulate. Can you cause any visible increase in the flow of saliva by this procedure? What is the purpose of tliis part of the experiment? Give some adrenaline and see if the pupils respond normally. Open the abdomen, follow the right side of the stomach around posteriorly and pick up the duodenum. In the angle between this and the stomach (inferiorih^) is located the pancreas. Refer to Figs. 244 and 245 and find the lower end (tail) of the pancreas. Follow this to the place Avhere 268 EXPERIMENTAL PHARMACOLOGY its attachment to the duodenum begins. The large duct (Fig. 245) opens into the intestine about one-half inch above this attachment. To find the duct take a probe and with great care gently dissect the anterior edge of the pan- creas away from the wall of the intestine. The duct will be found passing from the substance of the pancreas obliquely downward and inward through the intestinal wall. Pass a ligature beneath the duct as shown in Fig. 245 and then open the duct in the substance of the bowel wall. Insert a small cannula and tie it in with the ligature. Attach a short rubber tube to the cannula and bring it outside the abdomen which is now closed with hemostats. Give another dose of coniine and see if you get any secre- tion from the pancreas. Stimulate the vagi nerves and note any effect on pancreatic secretion. Kill the animal with a big dose of coniine. Immediately after death quickly open the thorax, pick up the phrenic nerves and stimulate them with a weak tetanizing current. Does the diaphragm con- tract I What theories do you know concerning the cause of death under coniine (Cushny: Journal of Experimental Medicine, i, 202) ? Dissect out the small duct of the pan- creas. What is the innervation of the pancreas? How is its secretion controlled! EXPERIMENT LIX. Atropine. (Frog: Heart and Vagus Nerve.) 1. Pith a frog and take a normal heart tracing showing the effects of stimulating the vago-sympathetic nerve and the crescent. Then while the drum is going pour two drops of atropine sulphate solution (one cubic centimeter equals one milligram) on the heart. After a few seconds stimulate the vagus trunk again. What do you observe f How do you explain it 1 Now stimulate the crescent. What do you ob- serve ? How do you explain this f 2. Cut out both of the frog's eyes. Examine the size ACTION OF ATROPINE 269 of the pupils carefully. Place one eye in a watch glass full of normal salt solution and the other in atropine solution. Place both glasses aside for ten or twenty minutes. Then again compare the size of the pupils. Do you note any va- riations? Explain the results. EXPERIMENT LX. Atropine. (Frog: Muscle and Nerve.) 1. From the frog used in Experiment LIX prepare two muscle nerve preparations from the sciatic nerves and gas- trocnemius muscles. Fill a watch glass with atropine solution and place the nerve of preparation A and the muscle of preparation B in the solution. From time to time stimulate both nerves with single shocks and determine whether or not atropine affects either nerve trunks or stri- ated muscle. Compare this with the action of curara. Stimulate the muscles directly a few times. What con- clusions can you draw? EXPERIMENT LXI. Atropine. (Turtle: Heart and Vagus Nerve.) 1. Repeat the experiment on the heart and vagus inner- vation described in Experiment LIX, 1, on the turtle. What conclusions can you draw from your results ? EXPERIMENT LXII. Atropine. (Cat, Guinea Pig, Rat, Dog, Pigeon, or Chicken: Pupil.) 1. Secure a dog, guinea pig or rat and a iDigeon or chicken. Into the right eye of each animal pour several drops of a one per cent solution of atropine with a medicine dropper. Place the animals aside and examine from time 270 EXPEKIMENTAL PHAKMACOLOGY to time to see if any changes are produced in the eyes. If so what explanation can you offer. If no change is pro- duced what explanation can you give ? EXPERIMENT LXIII.* Atropine. (Dog, Cat or Rabbit: Blood-pressure, Respira- tion, Heart and Vag^us Nerve, — Dog, Salivary Secre- tion and Chorda Tympani, Sweat Nerves, Pancreatic Secretion.) 1. Anesthetize a dog, cat (two grams urethane by stom- ach) or rabbit (two grams urethane by stomach) and ar- range for recording blood-pressure and respiration. Iso- late and ligate loosely both vagus nerves. The injecting burettes contain atropine (one cubic centimeter equals one- half milligram) and adrenaline (1:10,000). If a dog is used dissect out Wharton's duct and place a cannula in it (Figs. 237, 238, 239, and 240). Also isolate the chorda tyiupani nerve and stimulate it once or twice to observe the normal rate of salivary secretion. Some opera- tors tie a ligature on the chorda and cut the nerve centrally to the ligature. In this manner the ligature can be used to lift the nerve as desired. Generally it will be sufficient to stimulate the nerve in position without ligating it. (The dissection may be tried on a cat or rabbit if the instructor so advises.) Stimulate the vagi and obtain normal records of the ef- fects on the heart, blood-pressure and respiration. Observe the pupils (on the same side) as each vagus nerve is stimulated. If time permits, the student may dissect out the sciatic nerve (in dog) and stimulate it to observe the secretion of sweat on the sole of the foot. To do this take a piece of wet cotton and wash the pads of the foot off well, then dry *If more than one group performs this experiment, the second group may use scopo- lamine — one cubic centimeter equals one milligram — instead of atropine. ACTIOiSr OF ATROPINE 271 them and place the foot in such a manner that a good light can fall at a slight angle on to the pads. A hand lens may be used to considerable advantage. Stimulate the corre- sponding sciatic nerve and watch for minute droplets of sweat to form on the pads. On that side of the animal it is advisable not to place a cannula in the femoral vein but in- sert the cannula in the external jugular vein instead. Do not injure the circulation in isolating the sciatic nerve. Arrange all writing points on the drum (medium speed) and Avhile taking a normal (satisfactory) record begin to stimulate one vagus nerve mth a weak or medium strength of current (tetanizing). The current should be of just great enough strength to slow the heart markedly but not to com- pletely stop it. Do not continue this any longer than neces- sary or the vagus endings may be worn out. While thus holding the heart do^\m to a slow rate by a constant stimula- tion (increase the strength of the current if necessary) of the nerve inject two cubic centimeters of atropine solution (for a dog, — if a cat or rabbit is used inject one-half or one cubic centimeter of atropine solution). Continue the stimulation. Do 3^ou observe any change after the drug has had time to be carried to the heart in the blood? (Remember the circulation is slow and sluggish when the heart beats but slowly and the pressure is low). How do you explain your findings? Now inject another dose of atropine as soon as the animal can tolerate it. Then stimulate the opposite vagus nerve and note the effect on the heart rate and blood-pressure. Stimulate the chorda tympani and note the effect on salivary secretion. How do you explain this? Examine the sole of the foot (dog) carefully for sweat droplets (remove these if any are present) and then stimu- late the sciatic again. What conclusions can you draw? Were you able to get a sweat secretion by stimulation of the sciatic before the drug was injected? If not what does this part of the experiment show? Again stimulate one vagus 272 EXPERIMENTAL PHARMACOLOGY and watch the effect on the (corresponding) pupil. What changes, if any, do yon note? How do yon explain these! What effect has atropine in small doses on the blood- pressnre and respiration! A poisonous drug suddenly in- jected into the circulation often gives a fall of pressure due, according to some authorities, to irritation of the heart. Do you believe this explanation is sufficient to account for such changes! The vasomotor centers and the vessels, etc., may also be specifically involved. ^Hiat action has atropine on the vasomotor apparatus! If the experiment is performed on a cat or rabbit kill the animal with a large dose of the drug and secure a death record. If a dog is used inject a little adrenaline and ob- serve the action of this on the pupil (explain). Open the abdomen and insert a cannula (Figs. 244 and 245) into the pancreatic duct. Inject twenty cubic centimeters of .4% hydrochloric acid into the duodenum with a large hypo- dermic syringe and wait ten or twenty minutes to see if there is any secretion of pancreatic juice. How is the secre- tion of the pancreas controlled ! What action has atropine on this mechanism! What effect will stimulation of the vagus nerves now have on the pancreas! Try this (use slowly repeated single shocks). Inject some adrenaline and see if this affects the secretion. Kill the animal with a large dose of atropine, securing a death record of the blood-pressure and respiration. What is the immediate cause of death! 2. If time permits after the animal is dead, consult Fig. 281 and dissect out the optic nerve at the posterior side of the eye ball. Be careful not to injure the blood vessels. With scissors cut the skin and fascia outwards (backwards) from the outer canthus of the eye. Then seize the fascia over the back of the eye ball with forceps and roll the ball forward (inward). A mass of orbital fat and fascia will be seen behind the eye. Carefully dissect this away and watch for the optic nerve which is about three millimeters in di- SCOPOLAMINE, PILOCARPHsTE, ATP.OPINE Zi 6 ameter as it enters the eye ball. Place the tips of the elec- trodes on the nerve and carefully work the points into the substance of the nerve trunk. Watch the pupil closely and stimulate. Is there any action? Perhaps the animal has been dead too long. Do you think of any other reason? Master the technic of the operation for you will want to repeat it later. What is the innervation of the iris? How do these nerves get into the eye? Can you reach them in the way you have proceeded here? What are mydri- atics ? Myotics ? Cycloplegiacs ? EXPERIMENT LXIY. Scopolamine. (Frog: General Symptoms.) 1. Into the anterior lymph sac of a frog inject one cubic centimeter of scopolamine (one cubic centimeter equals five milligrams). Put the animal in a quiet place and observe the symptoms produced. What conclusions can you draw*? Examine the pupils from time to time and note the action on the lymph heart beats. Give a larger dose if necessary to bring on marked s>anptoms. EXPERIMENT LXV. Pilocarpine, Atropine. (Frog: Heart and Vagus Nerve.) 1. Pith a frog, take a normal heart tracing showing vagus and crescent inhibition and then while the drum is running at a fairly slow speed begin to drop on to the heart pilocarpine (nitrate or hydrochlorate) solution (one cubic centimeter equals one milligram). Watch for a slowing of the beat. The heart may be entirely stopped. How do you account for this? When the slowing has become very marked pour about three or four drops of atropine solu- tion (one cubic centimeter equals one milligram) on to the 274 EXPEKIMENTAL PHAEMACOLOGY heart and note the effect on the heart rate. How do you explain this! Stimulate the vagus and crescent again. 2. Cut out both eyes and place one in a normal salt solu- tion, the other in salt solution containing pilocarpine (one cubic centimeter equals five milligrams). Place the eyes aside for ten or twenty minutes and examine the pupils again. Can you detect any pupillary changes? What ex- planation can you offer? Fig. 241. — Lung tracing from a turtle showing the action of pilocarpine. EXPERIMENT LXVI. Pilocarpine or Arecoline and Atropine. Circulation.) (Frog: Retinal 1. Arrange a frog as shown in Fig. 164 and examine its retinal blood vessels with an ophthalmoscope. Find one or two very small vessels, preferably showing a branching so that the individual corpuscles can be seen moving into each di\dsion. Get a good notion of the rate of this movement for later comparison. Under the skin of the back inject two cubic centimeters of pilocarpine solution (one cubic centimeter equals two milligrams) or arecoline hydrobromide (one cubic centi- meter equals one milligram, Merck and Co.) solution. Descending^ \sympathetic fibres in spinal cord tmaxi Cervical sympathetic Fig. 242. — Schematic representation of the general plan of distribution of the nerves from the medullary centers to the salivary glands. This distribution is typical for a considerable number of other structures, glands, muscles, etc., located in the head. (Partially adopted from Eycleshymcr and Schoemaker.) Fig. 243. — Dissection of the submaxillary and sublingual glands and their ducts, certain cranial nerves and arteries and of the cervical sympathetic trunk and the superior cervical ganglion. (^Modified from Claud Bernard.) PILOCARPINE, ARECOLINE, ATROPINE 275 From moment to moment observe the eye ground and watch for any change in the rate of capillary movement. If you succeed well in getting a change, then with a tine pointed hypodermic syringe inject into the pericardium one-half cubic centimeter of atropine solution (one cubic centimeter equals one milligram). What changes do you observe in the retinal circulation? How^ do you explain this? EXPERIMENT LXVII. Pilocarpine or Arecoline and Atropine. (Dog, Cat, Rabbit, and Pigeon or Chicken: Pupil.) 1. Into the right eye of as many of these animals as may be available inject about twenty droios of pilocarpine (one cubic centimeter equals live milligrams) or arecoline (one cubic centimeter equals three milligrams) solution. Open the lids and fill the conjunctional sac as completely as possible and keep the solution in as long as you can. Into the left eye of each animal drop atropine solution (one cubic centimeter equals four milligrams). Leave the ani- mals alone quietly and at intervals of a few minutes com- pare the two eyes. Do you note any pupillary changes? Explain these. EXPERIMENT LXVIII. Pilocarpine, Atropine. (Dog: Blood-pressure, Respiration, Salivary and Pancreatic Secretions.) 1. Anesthetize a ten kilo dog (ether only) and arrange to record blood-pressure and respiration. Insert a cannula in Wharton's duct (Figs. 237, 238, 239 and 240) and dis- sect out the chorda tympani. Stimulate it and get a nor- mal secretion. Open the abdomen and insert a cannula into the large 276 EXPERIMENTAL PHARMACOLOGY pancreatic duct (Figs. 244 and 245). Stimulate the vagus nerve Avith a series of single shocks repeated at frequent intervals (does this stop the heart?) and see if you can get a flow of pancreatic juice. Keep this up for five or ten minuses if necessary. Thr ^e injecting burettes should be used, one in each iemor. i, vein and one in the left external jugular vein. Fig. 244.-y-A dissection showing the position and relations o£ the pancreatic ducts in a dog. I, intestine; O, omentum; M, mesentery; S, stomach; P, pancreas (tail); BD, position of bile duct (dotted, beneath the pancreas) ; LD, large duct, and SD, small duct of the pancreas. The pancreas is partly cut away to show the position of the ducts. This latter one contains adrenaline, the other two contain atropine (one cubic centimeter equals one milligram) and pilocarpine (one cubic centimeter equals one milligram). Observe the size of the pupils carefully. Then adjust all writing points and take a short normal record. Inject one cubic centimeter of pilocarpine solution. "What is the ac- ACTION OF PILOCAKPINE AND ATROPINE 277 tion of this drug on the heart and circulation? Is there any action on the glands? Be sure no atropine gets into the vein until you are entirely ready for it. When the animal recovers inject more pilocarpine. Be sure you get in enough to bring out the action of the drug well. The animal is not likely to die early if srnal doses are used. Note the action on the pupils, salivary glands and pancreas. How do you explain this? Inject one-half cubic centimeter of adrenaline and see how this counter- acts the action of the pilocarpine. Examine the pads of the feet and see if any small sweat drops are forming. (Re- member the circulatory disturbance you have caused in the hind limbs.) Inject more pilocarpine and try to get as marked action on the heart as possible. In a good typical case a long series of carotid tracings may be obtained in which separate heart beats may have an amplitude of from one-half up to three-fourths of an inch. When this stage is reached quickly observe the rate of salivary and pan- creatic secretion and then inject one cubic centimeter of atropine. This will not reach the heart for some time. Wait and see what happens. Explain all results observed. On what structures does each drug act? If necessary in- ject one cubic centimeter more of atropine. Now inject one-half cubic centimeter of adrenaline to restore the ani- mal. Stimulate the chorda tympani and the vagi. What effect has this on the salivary or pancreatic secretion? How does the vagus stimulation affect the heart, blood- pressure, and respiration? Observe carefully your record of respiration just after the pilocarpine was first injected. Is there a peculiar de- crease in amplitude with some difficulty in either expira- tion or inspiration? What possible explanation can you offer for this? How did the atropine affect it? Inject one cubic centimeter more of pilocarpine. Is the heart slowed? On what structures does atropine antago- nize the action of pilocarpine ? What is the action of pilo- 278 EXPEKIMEJSTTAL PHARMACOLOGY carpine on the adrenal glands? (Dale and Laidlaw: Jour- nal of Physiology, 1912.) Kill the animal with a large dose of pilocarpine and ob- tain a death record. Watch the pupils as the drug is in- jected. What do you observe? What is the immediate cause of death? If time permits open the chest and tit into it a piece of apparatus like that shown in Fig. 255 (or Fig. 256, if you happen to have this). Close the chest with hemostats as shown in Fig. 257. Could you do this in a living animal? Kemove and wash all your apparatus. EXPERIMENT LXIX. Pilocarpine, Arecoline, Adrenaline, Atropine, and Barium. (Dog: Bladder, Intestine, Respiration, Blood-pressure.) 1. Etherize a dog and arrange to record blood-pressure and respiration. Open the abdomen and connect a mercury bulb to the bladder in the manner shown in Figs. 179 and 199 and arrange to record bladder contractions on the upper part of the drum (the tambour pointer will rise when the bladder contracts — allow space for this.) Observe the apparatus shown in Fig. 246 for recording intestinal contractions. Arrange a burette, catheter and finger cot (or rubber glove finger) as shown and make a small longitudinal incision in a loop of tlie small intestine. Slip the end of the catheter over which the finger cot is at- tached about four or five inches down the lumen of the in- testine from the incision. (The tip of the catheter reaches entirely to the end of the finger cot and thus forces the cot along.) Fill the burette half full of water and move the catheter in and out a little to be sure the finger cot is filled ivith water and that the air is expelled. Stitch together the incision in the intestine around the catheter and close abdomen with hemostats. The intestinal tambour should Fig. 245. — Dissection showing the position and relations and the method of isolating the large duct of the pancreas in a dog. The method for inserting a cannula into the duct where it lies within the wall of the intestine is also shown. RECORDIjN^G INTESTIlSTAL COiS^TRACTIONS 279 write just below the bladder (the pointers must be able to pass each other), below this are the blood-pressure, respi- ration and base line. The injecting burettes contain pilo- Fig. 246. — Arrangement of apparatus for recording contractions of the intestine. (For discussion see text.) carpine (one cubic centimeter equals one milligram) and adrenaline. Take two inches (or less) of normal record and then in- ject one cubic centimeter of pilocarpine. A pronounced re- sult should be obtained in all the tracings. Do you get 280 EXPERIMENTAL PHARMACOLOGY this ? Wait for the action of the drug to become well de- veloped. If you are sure the dose was too small then inject a second (but one cubic centimeter is usually sufficient for Fig. 247. — Tracing showing the action of barium, adrenaline and atropine on the blood-pressure and intestinal contractions in a dog. The barium had been given just before this tracing begins. Its action on the inSestine is quite evident but the contrac-_ tions are checked, first by adrenaline (which stimulates the inhibitory endings) and. second by atropine. How do you explain this latter action? BARIUM, ADRENALINE, PILOCARPINE 281 average sized dogs). When the effects are well marked inject one-half cubic centimeter of adrenaline. What pilo- carpine reactions does this counteract? Your records should show marked results. ^ — (2WL.85 Fig. 253. — Tracing showing the action of adrenaline and barium chloride (after atropine) on the heart (myocardiogram) and blood-pressure. 286 EXPERIMENTAL PHARMACOLOGY ^.OuaUA, ™''^lil^ •'?'i''! i ■'■» '.uikii..\» C/^£,>Ax;t(n,yJU "I'M ,'€ift, i .^.OtAoti^ wmmiimMmmiif^^*\ mmm Fig. 254. — Tracing showing the action of a fatal dose of barium chloride on the heart (myocardiogram, right auricle and left ventricle) and blood-pressure in a dog. Note that the auricle continues to beat long after the ventricle has stopped. PILOCARPINE, ADRENALINE, ARECOLINE, ETC. 287 do YOU observe? How do you account for it? Pilocarpine acts very much like arecoline (as does also muscarine) but arecoline is much more powerful. Does atropine counteract all the actions of pilocarpine or arecoline! Do your records show this? Inject one-half cubic centimeter more of atropine. Then empty the atro- pine out of the burette and replace it with barium chloride solution (one-half per cent). Arrange all writing points and inject one cubic centimeter of arecoline to see if it acts as it previously did. Empty out the arecoline and replace it mth adrenaline. If the dog weighs ten kilos or more then inject five cubic centimeters of the barium solution (a smaller dose for a smaller dog). It will take about one- half minute for the action of the drug to become well marked (if the animal was in fair condition when the drug was injected). The reaction should be very marked. When this occurs inject one and one-half cubic centimeters of adrenaline. Does this counteract any of the actions of barium? On what structures does barium act? Did the previous administration of atropine affect this in any way ? Kill the animal with a big dose of barium and just after the death record is made quickly open the chest {with large tinner's snips) and observe the heart action. What is delir- ium cordis? "WTiat is fibrillation? EXPERIMENT LXX.* Pilocarpine, Adrenaline, Arecoline, Atropine, Barium. (Spinal Dog: Blood-pressure and Bronchioles.) 1. Etherize a dog (ten kilos) and arrange for blood- pressure records. Place injecting burettes in both femoral veins and one in the left external jugular. These burettes contain adrenaline (1:10,000), pilocarpine (one cubic cen- timeter equals one milligram) and arecoline (one cubic *Cats may be used for this experiment, but dogs are greatly to be preferred. EXPERIMENTAL PHARMACOLOGY centimeter equals one-half milligram). (Muscarine — one cubic centimeter equals one milligram — may be substituted for one of the last two drugs or be used separately if it is available.) Observe carefully the apparatus shown in Fig. 255. Flancie for sawed edge of sternum Biaphraqmattc ' surface Fig. 255. — A form of apparatus (approximately one-half natural size) made of, sheet brass to place in the chest to hold the walls rigidly wide open and air tight while the records of changes in the caliber of the bronchioles are taken. A dotted circle in the center of the curved plate shows where a window may be placed to great advantage if sufficient shop facilities are available to do this. The window may be made of a sheet of celluloid (such as is used in automobile curtains) or of glass, and if the window is removable this also adds to its usefulness. The curved wire at the base is made 9f 3/16 inch brass rod. Any tinner should easily be able to make up at a very small cost such a piece of apparatus, which can be made of "tin" (tinned iron) or galvanized sheet irori. The instrument may be used for recording bronchial contractions by use of either posi- tive or negative artificial respiration, but the latter (aspiration of the chest) is greatly to be preferred. (For the method of use see text.) KECORDING BRONCHIAL CHANGES 289 This ai3i)aratns works best when the air is intermittently aspirated out of the chest (25 or 30 times per minute — 45 millimeters of mercury negative pressure with the by- pass or inlet adjusted to give |)roper strength of suction to fill the lungs well). In the absence of a machine capable of giving negative interrupted pressure (see Fig. 360) pos- itive artificial respiration ma^^^ be used in the ordinary manner by blowing air into the trachea. Even a hand bel- lows may be used for this, but a i^ower driven machine is /G/asj window -Removeble cap Tube for aspirafion AdjusPeible ''y-P^'frm^^^^^^Flancje for sternum Diaphragmatic -#-!|^^^Bfi ^^^^^Costal surface SOrface tiotdi,for peric&rdi&l sac ^ inf vena cava Fig. 256. — Another form of apparatus for insertion into the chest to record bronchial •changes. About one-third natural size. The three wings at the bottom are placed inside the chest and are adjustable (by the thumb nuts) to fit various sized chests. When the cap (with a glass or celluloid window) is removed, the hand may be passed into the ■chest to massage the heart, etc. The movements and changes in the lungs and heart can be seen through the window. (For the method of use see text.) greatly to l)e i^referred. The ajDpaiatus shown in Fig. 256 may also be used for the lungs. The chest of the animal is now o^Dened by a median lon- gitudinal incision, the apparatus is inserted as sho^m in Fig. 257 and the edges are clamped around air tiglit with hemostats. It is often advisable to sew one or two stitches of heavy twine from side to side through the skin of the upper end of the chest. The flange of the apparatus catches the sawed eds-es of the sternum on each side and 290 EXPEKIMENTAL PHARMACOLOGY thus holds the chest open. As soon as the chest is opened artificial (positive) respiration is begun. Two forms of apparatus for thus giving ether to an animal are shown in Figs. 53 and 107. The artificial respiration thus begun is kept up throughout the experiment if only positive pres- sure is available. But if negative (interrupted) pressure is available this is substituted immediately after the ani- mal is pithed. If positive pressure is used then the closed chest acts as '^^/tdju stable by-pass Fig. 257. — Adjustment of the apparatus shown in Fig. 255 in the chest of a dog.. The sawed edge of the sternum catches against the flange of the apparatus and the skin- and fascia are brought up and clamped tightly with hemostats to the edges of the plate. One or two stitches may be taken to draw the chest together at the front end of the Piiparatus. If vosi ive artificial resvjiration is used this aopa'-atus simply converts the chest into a rigid-walled plethysmograph or oncometer for the lungs and heart. A glass- (or celluloid) window aids greatly by allowing the operator to see when the lungs are being sufficiently inflated. an oncometer and the tube to the recording tambour (which should have a large hoivl) is connected to the tube labeled "aspirate" in Fig. 255. Thus when the lungs are blomi full of air through the trachea and are thus expanded air will be forced out of the chest and into the tambour the pointer of which will rise. Conversely when the lungs col- PRELIMI]!TARY OPEEATIOj!^S 291 lapse air will be drawn into the chest from the tambour and the pointer will descend. If the bronchial muscles contract or dilate the extent of this movement will be cor- respondingly decreased or increased. The extent of ex- pansion or contraction of the lungs can be controlled by the screw clamp on the tracheal cannula (if the volume of air delivered by the respiration machine at each inflation cannot be independently controlled). The extent of move- ment of the tambour pointer, i. e., of the amount of air en- tering or leaving the tambour bowl, can be controlled by the screw clamp on the ''inlet" of Fig. 255. If negative pressure is used this is applied only after the dog is pithed (this being determined by the administration of the ether which is better done by positive artificial respi- ration). Figure 257 shows the way to arrange the tubes to the apparatus. In this case the tiihe to the recording tam- hour is attached to the side tube (or better the end) of the tracheal cannula (the ether bottle is removed, for it is no longer necessary as the animal will then be pithed). The other opening of the tracheal cannula carries a piece of rubber tubing and a screw clamp. This clamp is used to regulate the facility with which air passes into and out of the trachea and lungs. This regulates the size of the tam- bour stroke on the drum. Closing the clamp down in- creases the amplitude of the tambour stroke; opening the clamp decreases the stroke. The attachment of the tam- bour here and the removal of the ether bottle can be done only after the animal is pithed. When the apparatus is adjusted pith the animal. To do this consult Figs. 258, 259, 260, 261, and 262. Unfasten the dog's head and turn it on the left side. The anesthetist watches carefully to see that the cliest or trachea is not compressed and that the animal gets suf- ficient air ivhile this part of the operation is performed. With a scalpel make a median incision over the slmll and with large tin snips cut the skin away in a Y-shaped area 292 EXPERIMENTAL PHARMACOLOGY (Fig. 258). With a scalpel cut close to the hone and dis- sect loose the right temporal muscle. Keflect this upward and hold it up with forceps. Take a trephine instrument Fig._ 258. — Method of making the first incision before trephining the skull. The longitudinal (mesial) edge of the opening is cut with a scalpel. The triangular piece of skin and fascia is then lifted with forceps and cut away with heavy (6 inch) tinner's snips. o Fig. 259. — The trephine opening is made about one-half to three-fourths of an inch outward from the median line to avoid the great longitudinal sinus. (Fig. 100) and ma,ke an opening in the skull (Fig. 259). Be careful to avoid the longitudinal sinus — the opening should he one-half to three-fourths of an inch away from PITHING THE ANIMAL 293 the median line. Place a wad of cotton in the forceps and hold this in the left hand ready to cover the trephine open- ing. Pass a long narrow scalpel blade into the opening K ^^ ^P f ■-% ^^A iii^B i ■ '1im ^w ^^■^^ASi>^$^la\i. 1 ^^M :ri^S ^IVV %BS===S= ^^^^^^Sl Fig. 260. — Method of quickly cutting across the brain stem with a long narrow bladed scalpel while a wad of cotton is held in the forceps ready to crowd into the trephine opening to check all loss of blood. Fig. 261. — The cotton is held down firmly in the trephine opening while a probe is slipped in past the cotton and is moved quickly and thoroughly about in a circular manner to destroy every part of the brain. If the cord is also to be destroyed this is done by passing a long fairly flexible wire (one-eighth inch soft brass rod) through the trephine opening and out through the foramen magnum into the spinal canal. The head and neck may be moved a little to assist in passing the rod down the spinal canal to destroy the cord. and cut ciuickly across the brain stem. Eemove the scalpel and close the opening with the cotton. No blood should escape. Into the upper end of the opening beside the cot- 294 EXPERIMEISTTAL PHARMACOLOGY ton pass a probe (Fig. 261) and Avith a circular motion de- stroy every part of the brain. Kee^D the cotton plugged tightly in the opening. If it is desired to destroy the cord a one-eighth inch soft brass wire slightly curved at the end may l)e inserted past the cotton and forced through the foramen magnum and do^A^i the spinal canal. Bend the animal's neck and head a little to assist in getting the rod to enter the canal easily. Eemove the rod, plug the opening tightly with cotton, and replace the animal's head into its original position. Kemove the ether quickly, the animal will lie perfectly still and the blood-pressure mil Fig. 262. — After the brain (and cord, if desired) is destroyed the trephine opening IS plugged tightly with a wad of cotton forced in by the hooked end of an aneurism needle. The animal's head is then quickly returned to the usual position. fall to a height of about three-fourths to one inch above the base line as seen on the drum. If negative pressure is used change to this now. If pos- itive pressure is used attach the tambour and adjust all writing points on a slow drum, lung tracing at the top, below this the blood-pressure, and then the base line and time signal. The lung tracing should have an amplitude of about three inches. Be sure the manometer pointer will pass up just to the right of the tambour pointer. Take one-half or one inch of normal record. Inject one cubic centimeter of pilocarpine. Wait a little for the ef- fect to develop ivell. Then inject one-half cubic centime- PILOCARPINE^ ATROPINE^ MUSCARIXE, ETC. 295 2. » 3 ^ o cr W '5. o n Si w o fli 3 ^ c/> CI,-. £ 3 — '^ "'oil (U I-" <-! ^S-"" o ra to " n> o o o 3 ^ i i'" m 2 o ta ^ S cr C S- 3* n> ui o 29G EXPERIMENTAL PHARMACOLOGY ter of adrenaline. Wait — the blood circulates slowly. What do you observe? How do you explain it? What mechanical factors are concerned! A second contraction (ZdM^^^OLXlcfv\. Ficj 264— Tracing shcw'ng the action of local (Burroughs, Wellcome and Co.) on the blo°od-pressure and bronchioles in a spinal dog. The animal had received a dose ot pilocarpine a little while before this tracing begins and the bronchioles were Pfrtially contracted (tonus) from the action of the pilocarpine which exercises a prolonged ettect on the broncho-constrictor nerve endings. of the bronchioles will likely come on as the effect of the adrenaline passes off. Wait for this and give a second in- jection of adrenaline. (If the first dose of pilocarpine was ARECOLINE, ADRENALINE, ATROPINE^ ETC. 297 too small — this is seldom the case — then a second may be given but this reduces the vitality of the animal markedly and is best avoided.) Get the animal into as good condition as possible and (take a normal) inject one cubic centimeter {less if the animal is small) of arecoline solution. The response will probably be profound. Wait for the heart to beat slowly again. When the bronchioles are greatly constricted in- ject one cubic centimeter of adrenaline. Wait for the drug to be carried around. The result should be striking. How do you explain this? (If the first dose of arecoline was too small — this is seldom the case — then a second may be given but this is best avoided.) Empty out the pilocarpine {he sure the hull-dog on the vein does not leak) and fill the burette with atropine solu- tion (one cubic centimeter equals one milligram). Take a normal record and inject one cubic centimeter (or one and one-fourth cubic centimeters) of arecoline. When the action is marked inject one cubic centimeter of atropine. Wait for the drug to circulate. What do you observe? Explain all mechanical factors. Inject one-half cubic centimeter of arecoline. What conclusions can you draw? Empty out the arecoline and fill the burette with one- half per cent barium chloride solution. Barium acts pre- sumahly directly on the smooth muscle fibers. Remember the animal has had atropine. Take a normal record (the animal will probably be greatly weakened by this time) and inject five cubic centimeters of barium solution (three cubic centimeters if the animal is small). What do you observe? It will take some time for the action to become marked. Is the heart irregular? Barium acts somewhat like digitalis and in some respects resembles adrenaline. Do the bronchioles contract? If so inject two cubic centi- meters of adrenaline. Do they respond to this? Kill the animal with a big dose of barium. How does barium act on 298 EXPEKIMENTAL PHARMACOLOGY COuLOGCA^-^yJl w. mA^n^x^aJk. -.-/O^d-^UIo^ - C£o-iuiA hA y,,^,^;f(fflt>-''-^.'tvHt-->i^,,f,^if->*lt^^-'''^ \ \ /^ (M£S: if-t^^^^.C^J^^yU^to-^rySL, '^Z^'KrMicA Fig. 266. — Tracing showing the action of arecoline and atropine on the heart -/br washout pulmonary art Fig. 279. Fig. 278. — Special form of separable pointed cannula for the pulmonary artery. Fig. 279. — Special (all-glass) form of cannula for the pulmonary artery. The open- ing in the point should be about one-eighth inch in diameter (the pulmonary artery is large). 316 EXPEEIMENTAL PHARMACOLOGY of the ventricle before the manometer can be connected up. The puhiionary manometer should have its o^vn inde- pendent base line (which can be a wire fastened to the board of the manometer). It is most instructive to the stu- dent to use mercury in this manometer but sometimes wa- ter or salt solution is used instead. The comparison with the carotid pressure is seen at once if mercury is used. Sodium citrate solution is used to prevent coagulation. A T-tube placed in the tube going do^vn from the pressure bottle permits each manometer to have its own supply of citrate solution. When the cannula and tubing are all ad- justed for the pulmonary pressure {the manometer should have been fully adjusted previously) then wash out the tubes and manometer with citrate solution and fill the tubes full hut leave no 'positive pressure in the tubes. This- is of great hnportance. To accomplish best results a slight neg- ative pressure in the tubes is advisable. To g^i this fill the tubes and close both pinch cocks. Then open only the one on the washout. The pressure falls to zero in the manom- eter. Now between the thumb and finger squeeze the tube from the artery to the manometer. A small amount of the citrate solution runs out. Now close the washout and let go the tube. A slight negative pressure shows in the ma- nometer but the tubes are full of solution and no air is left in them. Work rapidly now for the animal may die soon and a clot is very liable to form in the pulmonary cannula. Ad- just all writing points, remove the pulmonary bull-dog and take a short normal tracing. Inject one-half cubic centi- meter of adrenaline and get a record. What effect has this on pulmonary pressure? Does the pressure rise higher in the right lung than it does in the left? Does your experiment demonstrate this? Explain. What nerv- ous structures are involved in this reaction? As soon as the normal is reached inject a dose of nico- tine (three-fourths cubic centimeter). Do you get a satis- PULMONARY BLOOD-PRESSURE 317 factory record? How does nicotine affect the pulmonary blood-pressure? What structures are involved? What mechanical factors are concerned? If you get a pulmonary clot put on the bull-dog and wash Artery. ' Us. ,CaA6tui ^(^^i^V(jLymJL, \.C^^ H-StA-crucU.. Fig. 280. — Tracing' showing the action of adrenaline on the pulmonary pressure, kid- ney volume and blood-pressure (right carotid) in a dog. The straight "line just below the pulmonary pressure tracing is the pulmonary base line. out the blood but be sure no positive citrate pressure is left in the tubes. This is necessary because strong (five to ten per cent) sodium citrate solution is very poisonous to the 318 EXPERIMENTAL PHARMACOLOGY heart and a small amount can easily pass back from the pulmonary artery into the right ventricle. This may kill the heart immediately. Could you use hirudin for this pur- pose! What objections could you offer? The average group of students will not get more than two good pulmonary pressure records from one dog. If the animal is still in suitable condition inject five cubic cen- timeters of barium chloride solution (one-half per cent). What conclusions can you draw? In how many ways may drugs affect the pulmonary blood-pressure? How many of these does your experiment illustrate? What differ- ences are there between the systemic and pulmonary cir- culation? Historically which of the systems was first dis- covered? By whom? Kill the dog with a dose of barium. EXPERIMENT LXXVIII. Nicotine, Pilocarpine, Atropine. (Dog: Intraocular Nerves, Salivary Glands, Oxygen Consumption, Blood- pressure and Respiration.) (For the anatomy of the eye, see Experiment CXVII, page 394.) 1. Give a dog (10 kilos) a moderate or small dose of chloretone and follow this with ether. Arrange to record blood-pressure and respiration. Consult Fig. 281 and dis- sect out the optic nerve in the right eye. (Consult Experi- ment LXIII, 2). Study Fig. 281 carefully and dissect out the orbit until the eye ball can be rolled around forward (in- ward) enough to bring the trunk of the optic nerve into view. The skin around the outer canthus should be cut away and sometimes the bones of the orbit must also be chipped out a little with bone forceps. Try to avoid dis- turbing the blood vessels entering the eye from behind. WTien the nerve is isolated place the platinum electrodes against the nerve sheath and, while Avatching the pupil,, INTRAOCULAll NERVES 319 stimulate the nerve. The pupil may dilate (sympathetic libers), contract (oculomotor fibers) or remain stationary (both sets of fibers or none of either). The electrodes are moved a little and the points can be worked cautiously down into the nerve trunk. Stimulate (for a moment only) at each new position of the electrodes, the pupil being watched carefully all the time. At some point in the stimulation the pupil will show a marked contraction at once. This is striking when properly done and will be well worth the time necessary to do the dissection within the orbit with especial care. Let each member of the group see the con- Fig. 281. — Method of dissecting out the orbital fat and fascia to expose the optic nerve. The position of the electrodes for stimulating the third nerve tibers is shown. The eye-ball is rolled forward (inward) somewhat to bring the optic sheath into view. traction and keep the observation in mind to check your later results. Now turn the dog's head back into the usual position and insert a cannula into AYliarton's duct. Stimulate the chorda tympani nerve and obtain a normal secretion. Arrange the apparatus for recording oxygen consump- tion and if necessary put a small amount of ether into it (but avoid the ether if you can). Into the femoral veins place injecting cannulas, the burettes to which contain nico- tine (%%) and adrenaline. Take some normal record (in- cluding at least one or two notches of the oxygen record). 320 EXPEEIMENTAL PHARMACOLOGY A good nicotine solution can often be made by scraping out the contents of the bowls and stems of two or three tobacco pipes. The material is dissolved in salt solution and filtered before being placed in the burette for injec- tion. The results are often striking. Inject a dose of nicotine (perhaps three-fonrths of a cubic centimeter. This will vary with the size of the ani- mal and also Avith the quality of the drug as usually ob- tained in the open market). Watch the pupils (both) as the drug is injected. Do you get a typical blood-pressure record! If it seems necessary inject some adrenaline to help restore the animal (watch the pupils as the drug is Fig. 282. — Bone cutting forceps. injected). What did your oxygen record show? On what does this depend? Inject another dose of nicotine (esti- mate the size to suit the tolerance of your animal). Stimu- late one vagus nerve and see if the heart is inhibited. If it is, give a little more nicotine cautiously. Stimulate the chorda tympani and see if secretion follows. When, on stimulation, the vagus no longer can inhibit the heart, empty out the nicotine and fill the burette Avith pilocarpine solution (one cubic centimeter equals one milligram). Substitute atropine for the adrenaline in the other burette. Inject one cubic centimeter of pilocarpine. What action has this on the salivary secretion and heart! Have you injured the vessels going to the salivary glands? Wait a little and if the animal Avill tolerate it Avell inject another PlLOCARPllSrE AND ATKOPINE 321 dose of pilocarpine. AVait for the action of the drug to become well developed. How is the heart affected ? Stimu- late one vagus nerve and see if this slows or accelerates the heart. If it beats faster or if the pressure rises how do you explain the result? Is this a natural phenomenon or have the drugs caused it in some Avay? When the action of pilocarpine is well marked (give more of the pilocarpine if absolutely necessary) inject one cubic centimeter of atropine solution (one cubic centimeter equals one milli- gram). Do you get typical results on the heart and blood- pressure f Stimulate the chorda tympani and see if secre- tion follows. Another smaller dose of atropine may be given if the animal will probably tolerate it well. Now stimulate the oculomotor nerve again and see if you get a contraction of the pupil. Stimulate the vago- sympathetic in the neck and see if the pupil dilates. If time permits dissect out the oculomotor nerve on the left side and stimulate it to see if contraction of the pupil will occur. Kill the animal with a big dose of atropine. If 3^ou do not have enough solution to do this (how much does it take?) then inject nicotine in addition. Examine the respiratory tracing just after the pilocarpine was injected. Do you note a decrease in the amplitude of the respiration with some difficulty in either expiration or inspiration? How do you account for this ? Is it central or peripheral f How did the atropine affect this? Did the atropine act centrally or peripherally? Could 3^ou obtain such phe- nomena as this in an animal whose head had been removed from the body? After the animal is dead pick up one vago-sympatlietic nerve trunk in the neck and follow it up toward the base of the skull. Dissect out the superior cervical ganglion and determine its relations to the surrounding structures. From this ganglion sympathetic fil)ers pass to the various organs, glands, involuntary muscles, etc., of the head. (See Fig. 243.) 322 EXPERIMENTAL PHAEMACOLOGY EXPERIMENT LXXIX. Lobeline. (Frog or Turtle: Heart and Inhibitory Nerves.) 1. Pith a frog or turtle and take a heart tracing includ- ing both vagus and crescent stimulation records. Make up a solution of lobeline sulphate containing approximately one milligram of the drug to one cubic centimeter of dis- tilled water. Lobeline sulphate is a dark, thick, viscid sub- stance and is difficult to weigh or measure but dissolves readily in water. While taking a record on the drum pour a few drops of the solution on the heart. Do you note any immediate action? Stimulate the vagus nerve and note the action on the heart. Now stimulate the crescent and see if you ob- tain the usual result. What conclusions can you draw? Have you obtained similar results with any other drug? Could you prove your conclusions in any other way? Ap- ply more of the drug to the heart to see the later results. How does lobeline act? (See Edmunds : American Journal of Physiology, xi, p. 79.) EXPERIMENT LXXX. Lobeline, Pilocarpine. (Turtle: Lung Tracing.) 1. Arrange a turtle for taking lung tracings (consult Experiment LXXIV, 1). When all adjustments are made take one-half inch of the normal (quiescent) record and then inject into the ventricle with a very fine-pointed hypo- dermic syringe one or two cubic centimeters of lobeline solution (one cubic centimeter equals one-half milligram). Do not disturb the lung tracing by manipulating the heart carelessly. Do you get a satisfactory lung record? How do you explain this action of the drug ? On what structures does lobeline act? Where are these structures located in LOBELINE, AKECOLINE, ATROPIISJ'E 323 •-I «, -I „ o cr? ft P H B-3- 324 EXPERIMENTAL PHARMACOLOGY the turtle 1 Do you have any evidence that these structures exist in the turtle? As soon as the curve returns to normal prepare to in- ^^ \\\m\\m\mMm Fig. 284. — Turtle lung tracing showing the action of lobeline. MatJi I I I 1 1 1 1 I n I n i n n nrfiTTn Fig. 285. — Turtle lung tracing showing the action of lobeline. ject pilocarpine (one cubic centimeter equals one-half mil- ligram). The heart may not be beating very strongly and if this is the case it may be advisable to Avait a few minutes for the heart to recover. A few drops of a dilute (1 :10,000) LOBELINE, PILOCARPINE, ADREXALIXE 325 adrenaline solution may be poured on the heart to ad- vantage. Prepare to take a second record and then inject one or two cubic centimeters of pilocarpine solution into the heart. Wait for the drug to act as the heart may be slowed or stopped and the solution may not reach the lung tissues for some time. Do you get a satisfactory record? How do you explain this! On what structures does pilo- carpine act? Do you have any evidence that such struc- tures exist in the turtle's lungs! What general conclu- sions can you draw from the experiment? Fig. 286. — Turtle lung tracing showing the action of pilocarpine. EXPERIMENT LXXXI. Lobeline, Adrenaline, Pilocarpine, Tetramethylammonium chloride. (Dog: Bladder Contraction, Blood-pressure, Respiration, Pupil.) 1. Arrange an eight kilo dog (the animal may be given a small dose of chloretone — 150 milligrams per kilogram of Aveight) for recording blood-pressure, bladder contrac- 326 EXPERIMENTAL PHARMACOLOGY aMnA. 3.r^,aA^l^i^/0<^'-ML^\^'}^^^&>^- ifcSBI^EiiH Fig. 287. — Tracing showing the action of lobeline (three injections) and heroine on the bladder, bronchioles and blood-pressure in a spinal dog that had previously received 3 milligrams (intravenously) of atropine. ACTION OF LOBELINE 327 Fig. 288. — Tracing showing the action of lobeline (two injections) on the bladder, bronchioles and blood-pressure in a spinal dog which had previously received a sufficient amount (135 mgs. ) of heroine to render the animal insusceptible to the specific action oi the drug on the bladder and bronchioles. Evidently here the first dose of lobeline produced ganglionic paralysis as shown by failure of response to the second dose. 328 EXPERIMEISTTAL PHARMACOLOGY tions, and respiration. Isolate and ligate loosely both vagi nerves. Stimulate one and watch the corresponding pupil- lary^ response. Keep this in mind for later comparisons. The three injecting burettes contain lobeline (one cubic centimeter equals one-half milligram), adrenaline (1:10,- 000) and pilocarpine (one cubic centimeter equals one mil- ligram). Take one inch of normal tracing. The bladder record (leave space for an upward contraction) should be on the upper part of the drum; below this are the blood-pressure, respiration and base line in succession. Be sure the blad- der tambour and manometer pointer will just pass each other on the drum (the tambour to the left). AYhen all is ready watch both pupils closely and inject one-half cubic centimeter of lobeline solution. There should be an im- mediate and profound response. Do the pupillary, blad- der and vascular responses all correspond? On what ana- tomical structures does the drug act to produce each of these reactions? Could ^''ou find these structures in a dis- section of the animal! Allow the animal to return to nor- mal. Inject one-fourth cubic centimeter of lobeline. Do you get a response corresponding to that produced by the first dose of the drug! Hoav do you explain this! Could you prove the truth or falsity of your conclusions ! How would you do this! When the records return to normal inject one cubic centimeter of pilocarpine solution. What is the action of pilocarpine after lobeline! Do these drugs coun- teract each other in any respect! Do your records show this! Explain the results fully. Inject a second dose of pilocarpine if necessary to get satisfactory records. Inject one-half cubic centimeter of adrenaline and see if the lobeline and pilocarpine have changed the response of the animal to the adrenaline in any way. A¥atcli the pupils closely as the adrenaline is injected. Now stimulate each vagus nerve and see how the heart, blood-pressure TETRAMETHYLAMMONIT ■ M CM I.ORIDE 329 Fig. 289. — Blood-pressure (and kidney volume) tracing showing tlie action of tetramethylammonium chloride before and after the injection of atropine. The first dose of tetramethylammonium chloride caused a great fall in pressure because the vagus endings in the heart were intact. The second dose, however, following paralysis of the vagus endings by atropine, caused a great rise in pressure. The kidney volume also actiz'cly shrinks. To what is this action due? 330 EXPERIMENTAL PHARMACOLOGY and pupils are affected. Is the respiration changed by the stimulation ? Have any of these phenomena been influenced in any way by the drugs If so, what anatomical struc- tures were involved and how were they affected? Are these structures ever involved in pathological conditions eHKch rubber tubing on the straight end of the tracheal cannula and the large hoivled tambour is adjusted to give a record of about three inches in amplitude placed just above the blood-pressure (which should be about three-fourths to one inch above the base line). Inspiration corresponds to the downstroke of the tambour. When all adjustments are made take three-fourths or one inch of normal record (be sure everything is working all right — otherwise readjust the apparatus). Now with care stimulate each or both vagus nerves and determine exactly what influence these have on the bronchioles. What con- clusions can you drawf Explain in detail. Take another normal and then inject one cubic centimeter {dog) of er- gamine solution. You should get an immediate response. If you do not the dose may have been too small (possibly de- teriorated drug — but this is rare) and you can let the animal recover and then give a larger dose. The right sized dose will give a profound bronchoconstriction. "\^^len this is at its maximum inject one-half cubic centimeter of adrenaline (or four cubic centimeters of hordenine solution) and note 376 EXPERIMENTAL PHARMACOLOGY the results. (See Fig. 312.) What structures are involved and how are they affected 1 As soon as you get one good tracing from the ergamine then empty it out and fill the burette (or connect a third wmmmm\\\ fljb.CcJu^Xd 11 1 1 I M 1 1 1 I I 1 1 1 M I I H M I 1 1 1 I 1 1 1 f 1 1 1 1 Ml 1 1 1 1 III llllllJIJli Fig. 312. — Tracing showing the action of ergamine (histamine, jS-iminazolylethylamine) and hordenine on the bronchioles and blood-pressure in a spinal dog. Curara had been burette to an external jugular vein) with atropine solution (one cubic centimeter equals one milligram). Start the drum and inject one cubic centimeter of the atropine. Then stimulate the vagus nerves and see if the bronchioles or BRONCHIOLE TRACINGS 6i ( 378 EXPERIMENTAL PHARMACOLOGY BRONCHIOLE TRACINGS 379 heart respond. AMiat coiiclusioii.s can yon draw from this ! Replace the ergamine into the burette (if it was emptied out before) and take a normal record. Inject a dose of er- gamine (gauge the size by your previous experience — the dose should be a little larger than that which was previously just sufficient to produce a maximum effect, for the animal becomes a little less sensitive all the time to the drugs). Fig. 315. — Tracing showing the action of arecoline, ergotoxine, (arecoline') and adrenaline on the bronchioles and blood-pressure in a pithed dog. 380 EXPEKIMENTAL PHARMACOLOGY Do you get a satisfactory record? Has the atropine changed the influence of the drug on the bronchioles f What does this prove? How does the action of hordenine com- pare with that of adrenaline? If the animal is still in a suitable condition (which is im- probable) you may try to get another contraction of the bronchioles from ergamine and then follow this with an in- jection of tyramine. This drug is described as acting in many respects like adrenaline. Will it dilate the bron- chioles ? Stop the artificial respiration and kill the animal. Dissect out both eyes and preserve them in fifty per cent alcohol (or ten per cent formalin) for dissection later. EXPERIMENT CVI. Ergotoxine, Erg-amine. (Cat, Guinea Pig", Dog, Rabbit: Uterine Strip.) 1. From one of the animals mentioned prepare a uterine strip and arrange to record its contractions as illustrated in Fig. 292 (or as in Fig. 316 if you have the apparatus). The drum should have a very slow speed. When all is ready take a normal record and see if you can determine whether or not the muscle is in a strong tonus, and if it is properly weighted. A good deal of experience is required to get the best results from the strips. Add one or two cubic centimeters of ergotoxine solution (one cubic centimeter equals five milligrams) to the salt solution in which the strip is suspended. Do you get a contraction ? If not add some more drug. Wait and see what happens. What conclusions can you drawl After a time change the salt solution and allow the strip to record a normal contraction. Do you need to change the weight? Now add two cubic centimeters of ergamine (five cubic centimeters equal one milligram) to the salt solution. What do you observe? Is it necessary to add more erga- XTTERTNE STRIP CONTRACTIONS 381 mine? AVhat conclusions can you draw? Chang-e the salt solution and then see if you can get a contraction of the strip by adding barium chloride (in one -half per cent solu- tion) to the beaker. On what structures does each of these drugs act? Air vent Fig. 316. — Arrangement of apparatus for recording contractions of a uterine strip, intestinal strip, or ring, etc. The metal water bath is made of a cheap metal water pail with a heating rod soldered through the side at the bottom. A short metal tube_ is soldered into a 1-inch opening in the bottom to receive a perforated cork for connecting with the Harvard muscle warmer inside. EXPERIMENT CVII. Ergot. (Cat: Action on Uterus.) 1. Secure a gravid cat as near full term as possible. Un- der the skin of the back inject with a hypodermic syringe two cubic centimeters of a good fluid extract of ergot. Put the animal in a quiet place and observe it carefully from time to time for several hours following. Discuss your con- clusions in detail. 382 EXPERIMEiSTTAL PHARMACOLOGY EXPEEIMENT CVIII. Pituitrin, Ergamine, Adrenaline. (Dog, Cat, or Rabbit: Uterine Contractions, Blood-pressure.) 1. Cats are preferred for the experiment. Observe care- fully the arrangement of the animal and the apparatus Burette in ext jugular vein Tube to- artificial respiration machine Fig. 317. — Arrangement of apparatus for recording contractions of the uterus in situ. (The experiment is difificult and often yields unsatisfactory results.) A somewhat similar arrangement may be used for recording intestinal contractions. shown in Fig. 317. The animal is given .3 to .4 gram per kilogram of body weight of chloretone (dissolved in alcohol) by stomach tube. Artificial respiration may be given throughout the experiment. Arrangements are made for recording the blood-pressure (omit this if sufficient appara- tus is not available), and injecting cannulas are connected with one femoral vein and one external jugular. These con- UTERINE CONTRACTIONS 383 tain ergamine (ten cubic centimeters equal one milligram) and pituitrin (one cubic centimeter to five cubic centimeters of water — Parke, Davis & Company's preparation is usually satisfactory, but several other extracts are on the market). The metal box in which the animal is placed is now filled with 0.9 per cent salt solution which is thereafter kept at 39° C. by a bunsen burner. This prevents exposure of the viscera to the cold air and avoids drying of the tissues. The abdomen is now opened by a long median incision and the intestines and bladder are pulled gently to one side and f£stened beneath the salt solution, thus exposing the uterine horns. One of these is followed up to the ovary which is gently dissected loose from its attachments (using great care not to disturb the blood-vessels) and the distal end of the uterine horn may also be freed a little from the body wall to permit freedom for its movements if contrac- tions occur. A myocardiograph (Cushny's, Wigger's, etc., or Fig. 141) is now placed down over the abdomen. A small round needle is used to pass two stitches of fine thread through the uterine horn about one inch apart. These stitches are used to attach the levers of the myocardiograph to the uterine horn. A very light recording lever (heart lever or light muscle lever) is attached to the myocardio- graph and arranged to write on the drum above (and slightl}^ to the left of) the blood-pressure record. The lever is weighted as nearly as can be estimated to suit the strength and tone of each uterine horn. When all adjustments are made a normal record is taken and then one-half cubic centimeter (for a full groA\m cat) of the pituitary solution is injected. Do you get a rise in blood-pressure? You should do so and this rise lasts for a considerable time. Wait for the curve (blood-pressure) to come back to normal. (Inject a larger dose if necessary to get a good record.) Did you get a uterine contraction? What explanation can you offer! Does this have any clini- cal significance? 334 EXPEEIMEISTTAL PHARMACOLOGY Now inject one-half cubic centimeter of erganiine (cat) and see what effect this has. Do you get a fall in blood- pressure! Will the animal be likely to die ? (If so, give it a small dose of pituitrin.) Did the uterus contract I If so on what tissues did the drug act and how were they affected? Wait a while for the animal to recover and observe any later actions of the drug. After a time more ergamine may be injected to get another record. If the animal is still in suitable condition adrenaline solu- tion may be substituted for one of the solutions in the bu- rette and a dose of this drug injected. How does the action of adrenaline on the uterus compare with, that of the other drugs given? AVhat is the innervation of the uterus ? (See Fig. 318.) Kill the animal by giving a large dose of one of the drugs you have. AVhat can you say about changes in the innervation of the gravid uterus in the cat? Does this hold also in the human uterus? Can you find this point in the literature ? This method of recording uterine contractions is some- times used to standardize ergot preparations by comparing the strength of the unknown solution with that of a standard preparation. (For literature, see Edmunds and Hale: loc. cit.; Dale, Dixon, Laidlaw, Barger: loc. cit., p. 363; Pitten- ger, P. S. : Biochemic Drug Assay Methods, P. Blakiston's Son & Co. ; also Dale : Biochemical Journal, iv, p. 427.) EXPEKIMENT CIX. Pituitrin, Erg-amine, Levulose, Adrenaline. (Dog: Thoracic Duct, Blood-pressure, Bladder Contractions, Respiration.) (Give the dog one-half pint of cream to drink three hours before the experiment.) 1. .Arrange a dog for recording blood-pressure, respira- tion and bladder contractions. Do not disturb the viscera Pilo motor muscle Lachrymaj^and Ndsal mucosa ..- -\ >^-^^ - - - ' ' !Spheno-palafigang. Sublingual yA—^^ P^''°^i^ g/aod^ gland r/j Submaxillary glancA^ U-.0 5ubmaxlllary(5ublingual} ^» ganglion Oall bladder and ducts. \ Cranial and Sacral nerves \^ motor = red nhibitory •-' Ttioracico-lumbar nerves inhibitory=green ^^ \^ Postganglionic fibers ' are dotted, thus— - c. N.XI Sup. cervical ganglion Thyroid gland Inf.cervical ganglion j;-Ansa subclavia 5tejlate (i?*- Thoracic) ganglion Sweat gland Small infest Pancreas lliocecal sptiincter Bladder Vesical sphincter Urethral sptiincter, Va so-motor fibers Pilo motor muscle Celiac (Semilunar) ganglion{Solarplex) Splanchnic nerves '^Sympsthetic chain Lumbar splanchnics Sup. Mesenteric ganglion Inf. Mesenteric ganglion hypogastric nerves Pelvic(tlYpoqa5tricJnferiHdc) ( sphincter plexus. [YeSical S( rectal portions) Pelvic'nerves (Nervus eriqens) 7? P HailecK Fig. 318. — Schematic representation of the involuntary nervous system. Fig. 319. — Dissection showing the method of isolating the thoracic duct at the root of the neck. Care should be taken not to perforate the parietal pleura at the apex of the chest if it can be avoided in making the dissection. RATE OF LYiMPH FLOW dOO any more than can be helped in putting in the bladder can- nula. Clamp the penis or vulva with a hemostat to prevent urination. Consult Figs. 319 and 302 and dissect out the thoracic duct. Place a cannula in it and collect the lymi)h as it drops from the small rubber tube placed on the cannula. The cannula must be very small, the opening in the end should be about the size of a ver}^ small thread and the outside of the tip of the cannula should not exceed %2 or %4 of an inch in diameter. Try to avoid penetrating the chest cavity at the apex in dissecting out the duct. If the chest is opened it may be necessary to give artificial respiration during the rest of the experiment. If the cream has reached the in- testine and is being absorbed well (two to three hours after meal) the thoracic duct in the neck should be of a whitish or 5^ellowish-white color and in an average sized dog will be about YiQ or %2 of an inch in diameter. The duct is com- posed of exceedingly thin and delicate tissue and can be easily torn off and lost in the dissection, the student per- haps not seeing it at all at any time. A little pressure mil compress the duct and check all out-flow from it. (Those students who have sufficient technical skill may also insert a cannula in the l^miphatic duct coming from the head and collect l3miph from both ducts at the same time. There is a very marked difference and the experiment is well worth doing.) The injecting burettes contain pituitrin (1 to 5 — Parke, Davis & Co.), ergamine (ten cubic centimeters equal one milligram) and adrenaline (1:10,000). When all adjustments are made take a normal tracing, watch the pupils and inject one cubic centimeter of pituitrin solution (dog, eight kilos or more). Do you get a rise in pressure, contraction of the bladder and a change in the rate and depth of respiration? If the dose was sufficient, as it probably was, allow the animal to return to normal and wait until the normal rate of hmipli flow is determined 386 EXPERIMENTAL PHAEMACOLOGY (number of drops per minute). The rubber tube or cannula may become clogged. If so pass a stiff twine string down the cannula and try to remove the clot. The pituitrin is now emptied out and the burette is filled External jugular vein Precava Axillary gi Bronchial glands receiving lymph lungs Lymphatic vessels from liver 5mall intestine Large intestine Vessel from abdominal wall Inguinal glan ■MailecH —Superficial lymphafics from head Submaxillary lymph glands Laryngeal glands Tracheal trunks Cervical glands ^Superficial lymphatics from limb Junction of thoracic duct with , , . . tracheal trunk Subclavian vein Lymphatic trunk eep lymphatic vessels from limb Lymphatics from thoracic wall — Vessel from diaphragm Thoracic duct Pancreas Aselli Lymph trunk from pancreas Aselli to thoracic duct -Receptaculum chyli Lacteal vessels and glands of mesentery Lumbar glands Iliac glands Vessels from limb Lymphatics from skin of leg Fig. 320. — Diagrammatic representation of the lymphatic system in a cat. (Partially adopted from Davison.) LYMPH FLOAV PITUITRUST 387 with levulose solution (five or ten per cent). In small re- peated doses (one-half or one cubic centimeter) several cubic centimeters of the levulose solution are injected. Wait then and see how the rate of lymph flow is affected. (How is the lymph flow from the head affected? Is this rate of flow maintained or does it decrease after a time!) After some time note the rate of lymph flow and adjust all writing points. Observe the pupils and inject one cubic centimeter of ergamine. Do you get satisfactory records"? If the dose was too small wait a while and inject a larger one to get good results. How did the bladder respond? How does this compare with pituitrin ? Inject adrenaline and see how this affects the lymph flow, bladder, pupil and respiration. With what other lymphogogues are you acquainted ? You may try some of these on the animal if it is still in suitable condition. Kill the animal with an injection of some of the drugs you have. Always get a death record in such cases and see which stops first, the heart or the respiration. How may drugs affect the rate of secretion or of flow of l^rniph? How is the formation of lymph controlled? What can you say about the innervation of the lymphatics 1 How does atropine affect lymph secretion? EXPERIMENT CX. Pituitrin. (Frog: Capillary Circulation.) 1. As in Experiment C, page 361, arrange a frog for ob- serving the capillary circulation in the web of the foot (Fig. 305). Observe carefully (for comparison) the normal rate of capillary flow and then inject one-half cubic centimeter (or more) of pituitrin under the skin of the frog's back. From moment to moment again observe the circulation in the web and see if any change occurs. If you note a change keep a careful w^atch on the animal from time to time for EXPERIMENTAL PHARMACOLOGY two or three hours and see if there is a return to normal. Keep the animal covered with a thin layer of wet cotton. EXPERIMENT CXI. Pituitrin. (Frog or Turtle: Heart Tracing.) 1. Pith a frog or turtle and take a normal heart tracing shomng vagus inhibition. Irrigate the heart with some pituitrin solution (1 to 5) and determine the action of the substance on the heart. Is the inhibitory apparatus in- volved in any way? How is the nmsculature of the heart af- fected? EXPERIMENT CXII. Pituitrin. (Turtle: Lung Tracing.) 1. Arrange a turtle for recording lung tracings. Stimu- late one vagus nerve and see if you get a contraction of the i^^^^-^a^Ayr^. mulummnmnaiummuiiumam Fig. 321. — Turtle lung tracing showing the action of pituitrin. lung. The magnification of the tambour tracing should be large. Take a normal and inject into the heart one cubic centimeter of pituitrin solution (1 to 5), What conclusions can you draw from your results ? ACTION OF PITUITRIjST 389 j9jiU2^^ /-r. i^c^;- /SM^:-(%^&tJUayudiuU ^^diAAAA. 2'^ .A>ii<^' Mmw^iMtmmmml^ Fig. 322. — Tracing showing the action of pituitrin on the uterine contractions and blood- pressure in a dog. Made by Barbour's method. 390 EXPERIMENTAL PHARMACOLOGY EXPEEIMENT CXIII. Pituitrin. (Guinea Pig, Cat, Dog, Rabbit: Uterine Strip.) 1. Cats or guinea pigs are preferred. Prepare a uterine strip and record its contractions. (See Experiment CVI, also Figs. 292 and 316.) After the strip is properly weighted and a short record has been taken add to the solu- tion surrounding the strip one cubic centimeter of pituitrin (1 to 20). Do 3'ou get a satisfactory contraction? Wait a while, the drum runs at a very slow speed. If after some minutes no change has been produced replace the salt solu- tion with a fresh supply and inject a larger dose of pituitrin. Could you standardize the size of the dose by the size of the contraction the uterine strip gives 1 If you had a standard preparation of pituitary extract could you com- pare ^\ith this the strength of an unknown sample ? If one- half as large a dose of the unknown sample were required to give a tracing three inches high, as was required of the standard preparation, what could you say of the relative strengths of the two samples? How much would you dilute the unknown preparation to bring it to the same strength as the standard"? This is essentially the method commonly used to standardize (assay) pituitary preparations for the market. (For literature, see Dale and Laidlaw: Journal of Physiology, 1910-11, xli, p. 318; Dale and Dixon: ibid, 1909, xxxix, p. 25 ; Dale and LaidlaAv : Journal of Pharma- cology and Experimental Therapeutics, 1912, iv. p. 75; Hamilton, H. C. : Journal American Pharmaceutical Asso- ciation, 1912 ; Roth, G. W. : Bulletin Hygiene Laboratory, No. 100; also Journal Pharmacology and Experimental Therapeutics, 1914, v. p. 557; Fenger: Journal Biologic Chemistry, 1916, xxv, p. 417 ; Frankl-Hochwart und Froh- lich: Archiv fiir experimentelle Pathologic und Pharma- kologie,. 1910, Ixiii, p. 347 ; Hamilton and Rowe : Journal of Laboratory and Clinical Medicine, 1916, ii, p. 120.) PITUITRIlSr, ADRENALINE, ATROPINE 391 EXPERIMENT CXIV. Pituitary Extract, Adrenaline, Atropine, Barium. Bronchial Contraction.) (Dog: 1. By one of the methods previously used arrange a dog for recording bronchial contractions. When all adjust- ments are made stimulate the vagus nerves and see how the SSfju^t^l-Qj^fli^'^tXia't'^ iiiiiiiimiiiiiiiiiiiiiiiiiiiiiiifiiiiiiffliml^rmT^^ I IHI Itlllll Fig. 323. -Tracing showing the action of pituitrin on the bronchioles and blood-pressure in a spinal dog. bronchioles react, then inject two cubic centimeters (dog — eight to ten kilos) of pituitrin solution (1 to 5). Do you get a satisfactory record! AVhat is the action of pituitary extract on the bronchioles? Is this a muscular or nervous affair? What action has pituitrin on the sympathetic nervous system? How does this compare A^dth adrenaline and tyramine? 392 experime:ntal pharmacology This dose was probably large enough (for some animals too large — the instructor may advise you about this) but if you think advisable try another dose to see if you can get more satisfactory results. When the animal recovers give one cubic centimeter of atropine, then stimulate the vagi and see if the heart is inhibited (how are the bronchi affected!). Give a little adrenaline to revive the animal and inject another dose (estimate the size) of pituitrin. How are the bronchioles affected now after the atropine? Would you advise the iise of pituitrin in bronchial asthma ! How do your results in this experiment compare with those obtained on the turtle lung? Kill the animal Avith a large dose of barium chloride solution (one-half per cent). How does this affect the bronchi? EXPERIMENT CXV. Pituitrin, Adrenaline, Aconitine. (Dog: Urine Secretion, Intestinal Contractions, Blood-pressure, and Respiration.) 1. Arrange a dog for recording the blood-pressure, res- piration and intestinal contractions (by the fingercot-bu- rette method). The injecting burettes contain pituitrin (1 to 5) and adrenaline (1:10,000). Carefully isolate both ureters (Fig. 162) and place a ureteral cannula (Fig. 213) in each. Arrange the cannulas to collect the urine flow in a beaker. Record on the drum the rate of drop flow with a signal magnet (worked by a simple key in circuit Avith a dry cell). Close the abdomen Avith hemostats and Avait ten or twenty minutes to get the normal rate of urine flow. (The drum should have a very sIoav speed.) When the normal rate of urine flow has been determined (if no urine is excreted after twenty minutes go on AAdth the experiment and Avatch for the flow to begin), take a nor- mal record and then inject one cubic centimeter (for eight PITUITRIX AND ACONITINE 393 to ten kilo dog) of pituitrin solution. How does this affect the blood-pressure? What happens to the respiration? Is this a central or a peripheral action? After the records return to normal (see that all pointers are recording properl}^) inject a second dose of one cubic centimeter and compare the results produced b}^ this with those obtained from the first injection. As soon as the records again reach the normal (keep the anesthesia regular) inject a third dose of one cubic centimeter. Does the animal become more or less sensitive to the drug? Is the rate of urine flow affected in any way? If so how do you explain it? Is the change as great as you expected? How does it compare with caf- feine or sodium sulphate? Continue giving pituitrin until five or six (or more) cubic centimeters have been given, watching for changes in the rate of urine flow in the mean- time. Do the intestines show any signs of increased ac- tivity? If so is this a nervous or muscular affair? Inject some adrenaline and see how this affects the urine flow and intestinal records. Do you see any signs of a tolerance being developed for the pituitrin? If so to what is it due? Does this occur with any other drugs? Could you stand- ardize an unkno"s\ai pituitary extract by comparing the ac- tion of various sized doses of the unknown mth a standard dose of a standard pituitary extract on the blood-pressure? This method is sometimes used to assay pituitary extracts. In that case small sized doses are given and a considerable period of time (fifteen minutes or more) is allowed to elapse between each two injections. If the animal is still in fair condition place a solution of aconitine "potent" {ten cubic centimeters equal one milli- gram) in the burette and determine what is tlie very least amount of the substance required to kill the animal. The injections must be made cautiously. AVatcli for postmortem intestinal contractions. Open the chest and see if the heart is fibrillating. 394 EXPERIMEiSTTAL PHARMACOLOGY EXPERIMENT CXVI. Pituitrin, Adrenaline, Vanadium. (Dog: Pulmonary Blood-pressure.) 1. In the manner described in Experiment CIV, p. 369 (also in Experiment LXXVII, p. 310) arrange a dog for recording pulmonary blood-pressure. The injecting bu- rettes contain pituitrin (1 to 5) and adrenaline (1:10,000). When all adjustments are made take a normal record and then inject one cubic centimeter pituitrin solution. Do you get a change in pulmonary pressure? Would you advise the use of pitnitary extract in a pulmonary hemorrhage from a tuberculous lesion? What structures are affected by the drug in the lungs 1 Would the drug be advisable in bronchial asthma! After a record showing the action of pituitrin on the pul- monary pressure has been obtained get the animal into as good condition as possible and fill one burette with a solu- tion of sodium ortho vanadate (two per cent — when the drug is dissolved in the water the solution is slightly alkaline). Add a very small amount of hydrochloric acid to neutralize the alkalinity, A bright, clear, orange-yellow solution will be produced. Take a normal record and inject two cubic centimeters of the vanadium solution. Was the dose large enough! If not, possibly you can still get another record with a larger dose. Kill the animal with the vanadium solution. What conclusions can you draw from the experi- ment? On what structures does the vanadium act? EXPERIMENT CXVII* Dissection of the Eye. — Its Anatomy and Pharmacology. Consult Figs. 324 and 325. It is advisable to read the section on the anatomy of the eye in some good text-book on anatomv. *It is expected that this experiment may be performed on a day when no other experi- mental material is available. 6phmder iridis Pupil Radial _, (dilator) ^ muscle of iris To ciliary muscle ciliary muscle \ Long aUary Dilatation of pupil Contraction of pupil mil Ciliary muscle (accommodation) '^- Kill (Contraction of pupil) "^ Electrodes (Dilatation or constriction of pupil; contraction of ciliary muscle) Electrodes' {Dilafafion of pupil, openinq wider of eyelids, or bulqinq forward of eyeball) Out'Qoinq sympathetic rami communicantes^ Sensory qanq/ion cell (Sensory nervesfrom eye reqior) ^'"^ ' ^Nucleusof^ origin iE— nerve Corpora ' Quadrigemina ■Position (:') of pupillodilator center N.vn N.VIIl \ N.VI Medulla oblongata Descending symp- athetic fibres in the 3pindl cord (sp.medulla) C at, dog, rabbi t I Thoracic n Ul itallesk Fig. 324. — Schematic representation of the innervation of the eye. Postganglionic fibers are shown as broken lines. y Endings of N. V (Sensory) in tissues of the eye Endings of N. Ill in \ /Cornea sphincter pupillae musde\ / /Anterior chamber (Aqueous humor) 5inus venosus sclerae W^==='''"~^"=^ /Posterior chamber {Canal of5chlemrn)-jO<^''~~'~^fS^^ fiber in ber bands around the tube to prevent unrolling. The eye is placed in the end of the tube with the opening in the sclerotic and choroid coats turned outward, i.e., the cornea and lens are directed to look through the tube. Point the open end of the tube to- ward an incandescent light or bright window and watch carefully in the exposed area at the back of the eye for an image of the light or window. If you detect any image state fully its characteristics and peculiarities. 396 EXPERIMENTAL PHARMACOLOGY Examine the cornea and pupil. Place the eye in a pan of water and make an incision around it in the line of the equator so as to separate the front half from the rear half. The incision may go through all three coats, but the vitre- ous humor should not be disturbed. Lift off the rear half of the coats and look into the cup thus formed. What color is the retina? Of what is it composed I What drugs act on the structural elements of the retina? What particular parts of the retina are involved in this action? Define the optic disc and the central artery of the retina. What is meant by the optic cup? What relation does it bear to the macula lutea ? Separate the sclerotic from the choroid and define the lamina fusca. Hunt for the ciliary nerves (and vessels) between the sclera and choroid. How do these nerves get into the eye-ball? Define the lamina cribrosa sclerge. Now take up the anterior half of the eye to which the vitreous humor probably remains attached. Look for the hyaloid membrane. What are its functions ? To Avhat is it attached? Gently separate the vitreous humor from the lens and ciliary processes and let it float in the water. De- scribe its color, consistency and functions. Have you seen anything of the ora serrata? Noav examine the ciliary processes and discuss their relations to the choroid and to the lens. Where are the ciliary muscle fibers ? What is the innervation of this muscle? What are its points of origin and of insertion ? What are its functions ? What drugs act on it and how do they act ? AVith care dissect away a small sector of the suspensory ligament of the lens. What is the canal of Petit? Where are the spaces of Fontana located and what is their func- tion? What drugs may influence this function and how? What is the canal of Sclemm ? Eemove the entire lens. If it is sufficiently transparent lay it over some small print and see if the letters can be seen through the lens. How many forms of lenses do you know? To which of these does the THE EYE AMYL XITRITE 397 crystalline lens belong"? How is the eye focused for vary- ing distances! What part does the lens play in this joroc- ess? Make two diagrams to show these actions. AVhat drugs may influence these processes and how do the drugs act! Examine the iris. Locate the anterior and posterior chambers. With what is each filled? May drugs influence these chambers in any way? If so how? Can 3^ou find any evidence of the existence of dilator muscle fibers for the pupil? Where would you look for these? What is the in- nervation of this set of fibers? What drugs act on the dilator mechanism and where and how do these drugs act ? How is the intraocular pressure controlled? How may drugs influence this ? Can you find the sphincter muscle of the iris? How is this muscle innervated? What part does it play in accommodation? What drugs may affect this muscle and how and Avhere do they act? Compare the iris of a bird with that of a mammal as regards the action of atropine, pilocarpine and cocaine. Make a diagram show- ing the structure and innervation of the eye and indicate thereon Avith ledger lines the points where all drugs which atfect the eye and with which 3^ou are familiar act. Indi- cate the nature of these actions with a plus ( + ) sign for stimulation and a minus ( — ) sign for depression and paral- ysis. Describe all nervous paths and elements involved in the pupillary light reflex. What is an Argyll-Robertson pupil ? EXPERIMENT CXVIII. Amyl Nitrite. (Student: Plethysmographic Record, General Action.) 1. Arrange your apparatus for taking a volume record of the arm as shown in Fig. 326. When all adjustments are made fold a handkerchief over a three (or five) minim amyl nitrite pearl and prepare to break the pearl by squeezing 398 EXPEEIMENTAL PHAKMACOLOGY it with a pair of pliers. (Pearls, or ampoules, are now pre- pared by several firms already covered by cloth so that glass particles can not fly off from the ampoule when it is broken.) Bring the pearl (or ampoule) up close to the sub- ject's nose and allow the vapors of the drug to be breathed in at once as the glass container is snapped by the pliers. Be sure you already have a normal plethysmographic record started (on a slow drum) before the pearl is broken. Fig. 326. — Plethysmograph for recording volume changes in the hand and forearm. The rubber band that connects the plethj'smograph to the arm may be made of the wrist or arm portion of a rubber glove (which may be bought in a ten cent store). The subject should be sitting (or lying) in a perfectly com- fortable position so that he will not move the hand into and out of the plethj'smograph while the record is being- taken. The drug is very volatile and in a few seconds it will have practically all disappeared. What does your record show? How do you explain the results? What general sensations does the subject feel? W^atch his face and neck closely for any flushing of the skin ACTIOiSr OF AMYL NITRITE 399 that may occur. Count his pulse and compare with the normaL Be sure to observe his rate and depth of breath- ing as the drug is inhaled. How do you account for the changes observed? EXPERIMENT CXIX. Amyl Nitrite. (Student: Pulse Tracing.) 1. Attach a sphygmograph to the wrist as sho^vn in Fig. 327. Take one or tw^o normal tracings and then prepare a strip of paper ready to record the action of amyl nitrite on Fig. 327. — Dudgeon's sphygmograph arranged for recording tracings from the radial pulse. the pulse. The subject should be in a perfectly comfort- able position. When all is ready break the pearl or am- poule and let the subject inhale the vapors. When the ef- fects come on markedly (in about ten seconds) start the clock work and run the paper through rapidly to record the changes in the form of the pulse curve. What can you say about the dicrotic wave? What is its origin and sig- nificance? HoAv does amyl nitrite affect it? What other 400 EXPERIMENTAL PHARMACOLOGY ■ rJ/otAn^ Fig. 328. — Tracing made with Dudgeon's sphygmograph showing the normal pulse record and a pulse record as affected by inhaling amyl nitrite. changes are produced in the pulse curve? How does the drug produce these? EXPERIMENT CXX. Amyl Nitrite. (Student: Corpuscles in Retinal Vessels.) 1. Obtain a piece of blue glass about four inches square. (It is often better to use two pieces of glass placed together to intensify the color.) Let the subject of the experiment lie down at perfect rest on his back before a large window through which he can see a large expanse of clear blue sky. (The sun should not shine on the student's face or on the blue glass plate.) The student now holds the glass near his face and looks through the glass up into the clear sky. He accommodates his eyes for a long distance and remains as perfectly at rest as possible. Presently a considerable number of small, almost circular, shadoAvy, ill-defined ob- jects will begin to appear in the field of vision. These ob- jects have a rapid, squirming motion, reminding one of the movements of an angle worm in water. The objects flit into sight suddenl3^ squirm about for an instant and then suddenly disappear. These objects are believed to be the ACTIOIT OF AMYLJ NITRITE 401 shadows of the corpuscles circiilgitiiig in the capillaries of the retina in front of the rods and cones. Observe carefully (but do not try to fix the eye on any given point) about how numerous these objects are in the field of vision. If the number were suddenly doubled or reduced by half, could you detect the difference f Do not strain your eyes in watch- ing for the objects as efforts in this direction will avail nothing and may even appear to decrease the number of shadows visible. Can you make out the shape of individual corpuscles? Do the shadows appear to move in set paths, i.e., within the lumen of the capillaries? Do any two or more shadows follow the same course as near as you can judge? When the student has learned the appearance of these shadows well and can readily estimate an}^ consider- able change in their number then, as the subject keeps watching the shadoAvs, an amyl nitrite pearl is broken near his nose and he quickly breathes in its vapors. A¥atch his respiratory movements closely. Does his face flush? The subject should not know what change to expect in the num- ber or movement of the corpuscle shadows seen by him. In what ways may amyl nitrite influence the appearance of these shadows? Explain in detail. EXPERIMENT CXXI. Amyl Nitrite. (Student: Retinal Blood Vessels.) 1. Through the center of a stiff, opaque card (calling card, or smoked, varnished drum paper) a pin hole is made. The card may be about two by three inches in size. The subject sits down at perfect rest in front of a window through which he can see a considerable expanse of clear, blue sky. A few objects, as the top of a building or a tree, may well be located about 200 to 400 feet in front of the window, so the subject by lowering his field of vision a little can see the upper part of these objects. The purpose of 402 EXPERIMENTAL PHARMACOLOGY this is to give the student a chance to knoAv when he has his eyes focused for a long distance (with which point most students are unfamiliar). The subject looks out into the clear sky (avoid sunlight) and holds the card in his right hand in front of and near to his right e^^e. The left eye is closed. The right eye looks through the pin-hole in the card and is focused for a long distance, i.e., the ciliary muscle is completely relaxed and the pupil is dilated. The card is now moved in a rotary manner in such a way that the pin-hole will describe a small circle in front of the pupil. The diameter of this circle should be about one-eighth of an inch or less and the circu- lar movement should be repeated at the rate of about two or three times per second. Thus a small ray of light will pass from the window through the pin-hole in the card, through the pupil and back on to the retina. Since the pin- hole is being constantly moved in a circle this ray of light will also be continually traveling round and round in a circle over the region of the fovea in the retina. This is a very unusual manner for light to enter the eye. As a result the blood vessels which are located in the anterior layers of the retina cast back their shadows on to the rods and cones in the posterior layers of the retina in such an unusual man- ner that these shadows are recognized by the subject. Their form and general distribution can be easily made out. It usually takes a long time for a student to learn to recognize these shadows correctly. He should focus his eyes for a long distance and keep moving the pin-hole round and round as he gazes through it up into the clear sky. The vessels, when finally recognized, will appear very much like the leafless tops of a number of trees ranged in a circle in such a manner that the tops all point toward the center but do not quite reach it, so that a small clear space is left en- tirely free from vessels in the center. This clear space cor- responds to the macula lutea or yellow spot. What do you know about this area? ' ACTION OF AMYL NITRITE 403 When the subject has learned to recognize clearly the size and appearance of these retinal vessel shadows he may determine the action of amyl nitrite on them. He should sit (or lie) at perfect ease, and his right hand should be free to keep up the circular movement of the card. While the card is moving and the vessels are being closely ob- served an amyl nitrite pearl is broken near the subject's nose and the vapors are rapidly inhaled. The subject watches carefully for any change in the size or distribu- tion (extension toward the macula or withdrawal there- from) of the retinal vessel. How may amyl nitrite affect these vessels? Explain in detail. EXPERIMENT CXXII. Amyl Nitrite. (Student: Effect on Vision.) 1. On the white, glazed surface of a sheet of drum paper make a circular spot one-fourth inch in diameter with black India ink. Behind the drum paper place several sheets of perfectly white writing paper (or a sheet of Avhite card- board) to give a perfectly Avliite background to the drum paper. The subject now sits quietly and looks at the black spot while amyl nitrite vapors are administered to him. Around the black spot the subject watches for rings of dif- ferent colors to appear. If these are observed how many are there, what is their arrangement, and what colors are seen? How long do they last? How does amyl nitrite act to produce this effect ? What is the embryological origin of the retina? If time permits it will be instructive to make a white spot on a black background and repeat the experiment by inhal- ing amyl nitrite vapors Avhile looking intentl}^ at the white spot. Do you know of any other drugs which will affect color vision? On what nervous structures may such drugs act? What relation does the retina l)ear to the cerebral cortex ? 404 EXPERIMEiSTTAL PHARMACOLOGY EXPERIMENT CXXIII. Amyl Nitrite, Nitroglycerine, Sodium Nitrite. (Dog: Blood-pressure, Respiration, Spleen or Intestinal Loop Volume, Blood.) 1. Prepare a dog for recording blood-pressure, respira- tion and the volume of either the spleen or a small loop of the intestine. The injecting burettes contain nitroglycerine (one-fourth per cent — the U. S. P. form is one per cent) and sodium nitrite (one per cent). Place a straight cannula in one femoral artery pointing toward the heart. Into a test tube draw off through this cannula five cubic centi- meters of blood and add to the blood two cubic centimeters of two per cent sodium chloride solution. Set the tube aside and draw off five more cubic centimeters of blood into a second test tube. Add to this tube two cubic centimeters of two per cent sodium nitrite solution. Shake up both tubes and let them stand for some time. Do you note any changes in either one? If so what and how marked is the change? If a spectroscope is available a one-half or one per cent solution of each may be made and compared as regards their spectra after the remainder of the experi- ment is finished. Take a normal record and prepare to give the animal some amyl nitrite. Proceed with this as follows : Keep the anesthesia as regular as possible. Open the side tube of the tracheal cannula and let the animal breathe mainly through this. Place a pearl on a towel and seize the pearl with a pair of forceps through the towel from below. In- vert the towel so as to form a ver}^ small tent-like chamber over the end of the side tube of the tracheal cannula. Be sure glass particles do not fly into the wind pipe. When all is ready (a good normal record is being taken) snap the pearl and let the animal breathe the vapors. The effect should come on promptly. It will not last long and after ACTION OF jSriTEITES 405 the animal fully recovers another set of records may l)e taken hj administering a second pearl. (Under special con- ditions yon may sometimes want to administer amyl nitrite to the animal by placing the drug in an empty ether bottle through which the animal is allowed to breathe tem- porarily.) Do you note any effects on the spleen or looj) of .0^ .Cay^-^ytCoL Fig. 329. — Tracing showing the action of nitroglycerine on the carotid pressure and the respiration in a dog. intestine? If so how do you account for the action? Is it an active or a passive affair ? AVhat mechanical factors are involved ? Explain ^\\j changes observed in the blood-pres- sure and resjDiration. When the animal fully recovers take a normal record and then inject two cubic centimeters of the nitroglycerine solution. Do you get a satisfactory record? (If not a sec- 406 EXPERIMENTAL PHARMACOLOGY ond dose may be given later.) Explain your results in de- tail. Let the animal recover, take a normal and then inject one cubic centimeter of sodium nitrite solution. Do you get a satisfactory record! (If not a second dose may be given later.) Explain your results in detail. For what purpose do you infer nitrites might be used clinically? If the animal is now in poor condition kill it with a large dose of nitrite. How much is required? But if the animal is in fair or good condition (as it probably will be) then al- low it to recover as fully as possible and proceed to per- form the next experiment on it. EXPERIMENT CXXIV. Nitrites, Pilocarpine, Adrenaline. (Dog: Bronchial Action.) 1. Arrange to record bronchial contractions by one of the methods previously given. (If the animal from Experi- ment CXXIII is used remove the spleen or intestinal onco- meter and close the abdomen tightly.) The injecting bu- rettes contain one per cent nitrogh^cerine, pilocarpine (one cubic centimeter equals one milligram) and adrenaline (1: 10,000). Pith the animal, adjust the recording instruments and take a short normal record. Inject one cubic centimeter of pilocarpine. This should produce a bronchoconstriction which will last for several minutes if no other drugs are given. When the bronchoconstriction becomes marked then inject two cubic centimeters of nitroglycerine solution. What action has this on the bronchioles? Would you ad- vise nitrites for bronchial asthma? Give one-half cubic centimeter of adrenaline. If the animal is still in suitable condition a further in- jection of pilocarpine (to produce an initial bronchocon- ACTIOX OF DIGITOXIN 407 striction) may be given and this can he followed hj an in- jection of sodium nitrite to determine the action of this body on the bronchial musculature. This is a point of con- siderable clinical interest. How does adrenaline compare with the nitrites as regards its power to dilate the bron- chioles! Would it make any difference whether the bron- choconstriction was due to nervous origin (as is the case with pilocarpine) or to a direct muscular stimulation (as occurs with ergamine) ? Which of these conditions exists in clinical bronchial asthma? Stop the artificial respira- tion and kill the animal. After the animal is dead open the chest, dissect out the heart and study carefully the position and relations of both auricles and both ventricles. Inflate the lungs and see how much these would be in the way in taking myocardiograms. EXPERIMENT CXXV. Digitoxin. (Frog: General Action.) 1. Destroy the cerebrum only of a frog and inject one cubic centimeter of digitoxin solution (one cubic centimeter equals one milligram — dissolve the digitoxin in a few drops of alcohol and then dilute with water, adding more alcohol if necessary to prevent precipitation of the drug. Use as little alcohol as possible.) Put the frog in a quiet place and see if any generalized s3miptoms appear. Does it have con- \u.ilsions? If the frog dies at any time immediately cut open the chest and observe carefully the condition of the heart. Has it just stopped beating or is it still pulsating? Digitalis solutions are often standardized by giving just a sufficient dose of the preparation to stop the heart of a frog in one hour. This dose of the standard solution is taken as a basis, by comparison with Avhich newly prepared solu- tions are standardized. Examine carefully the condition of the ventricle and of the auricles. Are these chambers in sys- tole or diastole? How do you account for the condition? 408 EXPERIMENTAL PHARMACOLOGY EXPERIMENT CXXVI. Digitoxin. (Frog: Heart Tracing.) 1. Pith a frog and take a normal heart tracing showing both vagns and crescent inhibition. Then drop onto the heart slowly a solntion of digitoxin (five cubic centimeters equal one milligram — dissolve the drug in a little alcohol and dilute to the desired strength, adding more alcohol if absolutely necessary.) After the drug has acted for a little time stimulate the vagus nerve and see if the inhibitory apparatus is paral- yzed. How is the tone of the heart affected? Is this a nervous or a muscular action? Continue the application of the drug and record the entire action on the heart. When this heart stops compare its condition with that of the heart of the frog used in the preceding experiment. A'\Tiat con- clusions can you draw? EXPERIMENT CXXVII. Digitoxin. (Turtle: Heart Tracing.) 1. Repeat Experiment CXXVI using the turtle's heart instead of that of the frog. Is the inhibitory apparatus af- fected? EXPERIMENT CXXVIII. Digitoxin. (Dog or Cat: Blood-pressure and Respiration.) 1. Etherize a dog or cat and take a normal record of blood-pressure and respiration. The injecting burette con- tains digitoxin solution (ten cubic centimeters equal one milligram — dissolve the drug in alcohol and dilute with water to the proper strength, adding more alcohol if abso- lutely necessary). When the normal is recorded (be sure the manometer pointer can pass just to the right of the re- ACTION OF DIGITOXIN 409 spiratory tambour) inject sloAvly and cautiously one-hall" cubic centimeter of the drug. Caution : Digitoxin preparations on the market are exceedingly variable in strength and composition. Each preparation must be tested before the size of the dose for an animal can be determined. The object here is to give very small doses and bring on the action of the drug very slowly. Sl-CoAa^^ \m!^\m\\\m\m\\\m\mM^{mm\\ Fig. 330. — Tracing showing the action of one milligram of digitoxin on the blood-pressure and respiration in a dog. Slow drum. AVatch for any slight changes in the amplitude of the manometer tracing. The drug should first slow the heart slightly. The pressure may be somewhat elevated during this period which corresponds to the therapeutic (1st) stage. As the action of the drug becomes more marked the heart is greatly slowed (2nd stage) provided the inhibitory apparatus is Avorking normally. The center is stimulated by the drug and this indirectly slows the heart by inhilntion. Give a few small injections slowly from time to time at first 410 EXPERIMENTAL PHARMACOLOGY CO •n C °'^ 2-a actiojST of digitoxin 411 to avoid killing the animal too quickly (some preparations are exceedingly poisonous). As soon as you determine the tolerance of the animal to the solution make larger and more frequent injections, watching carefully for the marked jAaiiiiiiar .&;u JS^^. i«.«. J9,i^ct6^^^ AiAfttlMAiiiiililllTiiiiiiiiiliiiiiiiil c/'-cJ^-e-o-***^. c/^ Fig. 332. — Tracing showing the blood-pressure and respiration of a dog under the iniluence of di.gitoxin at the time when the second stage passed over into the third stage. Several small doses of the drug were given from time to time to bring on this action. slowing of the second stage to appear. AYhen once you see clearly that this slow stage is beginning then stop all in- jections and wait for the drug to act. There Avill then prob- ably be sufficient drug in the animal to cause death and it 412 EXPERIMENTAL PHARMACOLOGY ACTION OF DIGITOXIN 413 ■5 rt 414 EXPERIMENTAL PHARMACOLOGY is desirable to prolong the later stages as much as possible to bring out the action of the drug well. When marked slowing is present (vagus center stimu- lated) the blood-pressure may be considerably loAvered. After a time irregular heart beats appear and the elevation of the pressure varies from moment to moment. Watch carefully now, for great irregularity of the heart ma}^ sud- denly appear at any time, i.e., the vagus may lose control of the heart whose muscle fibers become so irritable that the organ breaks loose from the inhibition and begins to beat very rapidly, and irregularities, extra systoles, etc., soon appear. When this very rapid (3rd) stage appears the pressure may continue high for a little while but de- lirium cordis (fibrillation) is likely to appear at any mo- ment. When it does the pressure will fall to zero at once, perhaps from a considerable height. The respiration will stop at about the same time as a rule. Watch carefully for the animal to die, and as soon as the pressure suddenly falls to zero {and remains there) open the chest quickly with large tinner's snips and observe the condition of the heart. It should be fibrillating. Are the chambers in sys- tole or diastole. Place your hand on the heart and note the character of the movements. How long does the fibrilla- tion last? Can you determine the three stages of the drug's action on the heart as shown by 3^our record? What con- clusions can you draw from the experiment? How much drug is required to kill the animal? Could you assay the strength of an unknown preparation of digitalis by compar- ing the size of the lethal dose of the preparation with the size of the fatal dose of a standardized preparation? On this basis a number of methods for assaying the strength of preparations of digitalis and related bodies have been proposed. (For literature, see Houghton, E. M. : The Lancet, 1909, June 19; Hatcher and Brody: Journal of Pharmacology, 1910, August, p. 362 ; Famulener and L^^ons : Proceedings of the American Pharmaceutical Association,, DIGITOXIN, STEOPHANTHIN, NITROGLYCERINE 415 1902, p. 417; Vanderkleed and Pittenger: Journal of the American Pharmaceutical Association, 1913, xi, p. 558; Edmunds: Hygienic Laboratory Bulletin No. 48; Hatcher: Journal of the American Medical Association, 1910, ii, p. 1697 ; U, S. P. ix, p. 606 ; Pittenger and Vanderkleed : Jour- nal of the American Pharmaceutical Association, 1915.) EXPERIMENT CXXIX. Digitoxin, Strophanthin, Nitroglycerine. (Dog: Pulmonary Blood-pressure, Carotid Pressure.) 1. Arrange a dog for recording carotid and pulmonary blood-pressure tracings according to the method learned previously. Place cligitoxin solution (five cubic centimeters equal one milligram) in one injecting burette and strophan- thin solution (five cubic centimeters equal one milligram) in the other. When all adjustments are ready take a short normal rec- ord and inject one cubic centimeter of digitoxin. Wait for the animal to recover. When the records return approxi- mately to normal inject one cubic centimeter of strophan- thin. Do you get satisfactory records from both drugs? How is the pulmonary blood pressure affected f Does this correspond with the systemic circulation? Do the two drugs act alike on the pulmonary vessels! Which is the more powerful? If these doses were too small to produce any noticeable result give another larger injection of each one to secure satisfactory tracings. Now empty the digitoxin out and fill the burette (or, bet- ter, connect a third burette to a neck vein at the start) with one-half per cent nitroglycerine. Take a normal quickly and then inject one cubic centimeter of the nitroglycerine solution. Do you get a satisfactory record! If so how is the pulmonary pressure affected? Does this have any special clinical significance? How does it compare witli digitoxin? 416 EXPERIMENTAL PHARMACOLOGY Eeplace the digitoxin in the burette and continue the re- cords. Inject more digitoxin and strophanthin from time to time and slowly bring on the action of the drugs. Watch that the animal does not die suddenly from some unknown cause and the drugs be accepted as the cause of death. Ani- Detail of rubber baqs Glass tube Bdnd to attach bowls to lobe of liver Tube to ( tambour li Ha I feck. Fig. 335. — Schematic illustration showing the principles involved in the construction of Edmunds' liver oncometer. The two curved spoon-shaped pieces are made of dental impression compound. This is a brownish substance (resembling sealing-wax) which softens and becomes easily moulded with the hands when placed in hot water for a while, but hardens on cooling. Obtainable from dental supply houses. Thin flat rubber bags fit inside the curved pieces and these bags tit just over the outside of the left lobe of the exposed liver. Records are made by air transmission to a tambour. mals arranged for recording pulmonarj'' blood-pressure often do not live long and it is important to work rapidly and accurately. Can you detect any evidence that the heart has been especially stimulated or strengthened by the drugs ! Do you know of any other drugs previously studied DIGITOXIN AND STROPHANTHIN 417 that resemble the effects of digitalis in certain features of their action? Crowd on enough digitoxin or strophanthin to kill the animal after a few minutes. If you detect the marked slow- iiiiii 1 ! / X /-J0,OOO mill'*''* ^a^:-7S^aU.Stl^. . iff iinmiiiTmTilmiiMiiiiiffiiiff^^ mill 1 Fig. 336. — Tracina; shewing the action of adrenal ne on the volume of the left lobe of the liver and on the blood-pressure. Made with the apparatus shown in Fig. 338. ing of the heart indicative of the second stage then stop giving drugs and wait for the full effects of the substances to develop. Do you get the third stage of great irregular- ity followed b}^ delirium cordis and death? 418 EXPERIMENTAL PHARMACOLOGY After a time kill the animal with a large dose of one of the drugs if it has not already died as indicated above. Watch the heart closely throughout the experiment and see if you can follow the changes occurring in the auricles and ventricles. If delirium cordis sets in which chambers are affected by it first? Is this of any clinical significance? Can you detect this on the carotid record? Would this signify anything of importance from a clinical standpoint? Are the vagus endings in the heart paralyzed during the third stage? Could you determine this point during your experiment in any way? EXPERIMENT CXXX. Dig-itoxin. (Dog: Heart Tracings, Carotid Pressure.) 1. Arrange a dog for recording tracings from both auri- cle and ventricle as was done in previous experiments. If simple heart levers are used the right auricle and right ven- tricle will probabl}^ be the easier for the student record. If a Cushny myocardiograph is available the left ventricle can very well be used. If only one chamber can be recorded then the left ventricle is preferred. The records should be arranged with the auricular tracing at the top of the drum, below this the ventricular tracing, then the carotid pressure, and finally the base line (show- ing the time also). The injecting burette contains digitoxin (five cubic centimeters equal one milligram). When all adjustments are made take a normal record and begin to inject digitoxin in very small repeated doses, wait- ing a little while between each dose to see what its effect will be. The object now is to bring on the action of the drug slowl}^ and to watch to record the changes in each chamber as the three stages develop. When the marked slowing of the second stage first begins to appear (due to stimulation of the inhibitory center in the medulla) Avatch carefully to see whether the auricles or ventricles first ACTIOj!^ of DIGITOXIN 419 sliow the retardation. Do the two auricles beat in alternate rhythms or synchronously I Does this hold true for the ventricles also? Stimulate one vagus nerve from time to time (do not injure the nerve by drying, etc., or by too strong a current) and see if its connections with the heart muscle are destroyed at any time. Inject more drug from time to time until the second stage is well developed. AVait then and do not give any more drug unless it appears to be absolutely necessary to bring on the last stages. When the stage of irregularity appears (third stage) ob- serve carefully Avhich chambers of the heart first take up the rapid rhythm. Is this due to paralysis of the vagus endings 1 CavMon: Sometimes the second stage of marked slowing is not developed in the heart (inhibitory mechanism weakened or paralyzed) and the pulsations take on a rapid character early in the intoxication and the stage of irregularity may follow after a brief interval. Slow administration of the drug at tirst is best calculated to bring on the stage of marked inhibition. When the heart becomes very irregular observe the cor- responding changes in pressure. Watch for the sudden de- velopment of delirium cordis (fibrillation) and note which chambers first show this phenomenon. Do the other cham- bers begin fibrillating at once or only after a considerable interval! How does delirium cordis affect the blood-pres- sure? What can you say about delirium cordis in the frog or turtle? Do you get satisfactory tracings from the heart showing all the stages of the poisoning! Do you believe it would be possible to standardize digitalis preparations according to the amount of the drug necessary to bring on the different stages in the heart action ! On what do you base your con- clusions! What is the cause of death in digitoxin poison- ing! The administration of the drug should be continued (at long intervals) until the animal dies — which will prob- ably be rather suddenly. Judging from your experiment what should be the clinical symptoms of the first or thera- 420 EXPERIMENTAL PHARMACOLOGY peutic stage of the action of digitoxini Discuss the action of the drug on the heart in detail. '■t) EXPERIMENT CXXXI. Digitoxin, Strophanthin. (Dog: Diuresis, Spleen Volume, Leg Volume, Blood-pressure and Respiration.) 1. Arrange a dog for recording hlood-iDressure and leg volume. Then open the abdomen and isolate both ureters near the bladder. Place a cannula in each ureter and ar- range to collect the urine secreted. Now place the spleen in an oncometer and arrange to record the volume changes of the organ. On the drum the s^Dleen volume should be at the top, next below the leg volume, then the blood-pressure and respiration with the time marked on the base line. The Tate of urine flow may be recorded mth a signal magnet by a hand key and dry cell if desired. The injecting burettes ■contain digitoxin (ten cubic centimeters equal one milli- gram) and strophanthin (ten cubic centimeters equal one milligram). When all is ready wait a while to get a record of the nor- mal rate of urine secretion. Then take a normal record and inject one cubic centimeter of digitoxin solution. Is the dose too small? Give one cubic centimeter of strophanthin. Which affects the animal the most? Inject a few more doses very cautiously and then wait for some time to see if the rate of urine flow is changed. If it is how does this com- pare with the action of caffeine or sodium sulphate? After time has been given for an action on the kidney to develop (is this certain to occur?) then adjust all writing points and take a normal. Then inject a good sized dose of digitoxin as estimated from your previous experience with the drug and with the animal. How does this affect the spleen and leg? Do the other records show a correspond- ing action?. Wait a while and give a similar injection of strophanthin. How does the action of this drug compare SPLEEN ONCOMETER 421 3Tiap / Noich for Meseni-erv of Spleen. Fig. 337. — Spleen oncometer made of crimped sheet brass soldered together. Nearly natural size. (For a dog.) 422 EXPERIMENTAL PHARMACOLOGY with the cligitoxin? Are the vessels of the internal organs and of the leg both affected in the same Avay and in corre- sponding degrees by these two drugs? (See Edmunds: Fig. 338. — Liver oncometer, for the left lobe of the liver of a dog. Made of crimped sheet brass. The lid (raised up) is slipped under the lobe and the cup-like part closes over the lobe to inclose it. The "pedicle" of the lobe passes through the large notch at the right in the picture. The spout is connected to a tambour and the abdomen is closed air tight. American Journal of Ph^^-siology, xviii, p. 129.) What can you say about the action of the digitalis series of drugs on the medullary centers 1 ( See Hatcher and Eggieston : Jour- LIVER VOLUME CHAjSTGES 423 nal of Pharmacology and Experimental Therapeutics, iv, p. 113.) . Do these large injections of the drugs affect the kidneys? Fig. 339.— Tracing showing the action of tetramethylammonium chloride on the liver volume and blood-pressure in a dog. The respiratory movements show in the oncometer tracing. The animal was breathing deeply. Made with the oncometer shown in i-ig. 3Jt-. In what ways might they influence the secretion of urine? When satisfactory records have been obtained inject a large dose of one of the drugs and get a death record. 424 EXPERIMEiSTTAL PHARMACOLOGY Have you shown all three stages of the heart action in your experiment 1 What general conclusions can you draw from the experiment? EXPERIMENT CXXXII. Adrenaline, Potassium Chloride, Digitoxin, Strophanthin. (Cat, Rabbit, Dog: Heart Perfusion — Langendorff Method.) 1. Set up your apparatus with great care in the manner shown in Fig. 340. Prepare several liters of stock salt solu- ,tion (Locke's preferred). Place two liters of the solution in the pressure bottle and heat the water bath to 39 de- grees centigrade. Place water in the heart warmer (a hot water funnel may be substituted for the cheap heart warm- er here shown) and heat the warmer to 39 degrees centi- grade. When all apparatus is arranged, including the adjust- ment of the cannula (lower end of a glass T-tube with a neck drawn on it) for insertion into the aorta, then etherize the animal and connect a burette to one femoral vein. A straight cannula is placed in one carotid pointing toward the heart to bleed the animal. Draw off as much blood as will flow readily out of the carotid and whip this until the fibrin is all removed. Meanwhile siphon off a liter and a half of the warmed salt solution from the pressure bottle and inject a liter or more of the warm solution into the femoral vein. This will revive the animal somewhat and it may then be bled further from the carotid. All the blood is carefully saved, whipped free from clots, filtered through cloth or cotton and placed in the pressure bottle (which con- tains now one-half liter of warmed salt solution). This mixture of whipped blood and salt solution forms the stock perfusion fluid. More salt solution can be added to it to bring the volume up to four or five times its original amount or more. HEART PERI'^USIOIS^ APPARATUS 425 Funnel (refilling 5- air vent) Stock solution (Diluted blood -h a salt solution) l^eral pan Hot water batti Fig. 340. — Arrangement of apparatus for recording tracings from an excised heart (Langendorff method). The heart warmer is made of two cheap metal pails held together by a. metal tube soldered between them at the bottom. Through this tube passes the thread attached by a pin hook to the heart. The space between the pails is filled with water heated by the flame of a Bunsen burner applied to the heating rod. 426 EXPERIMENTAL PHARMACOLOGY lAHien no more blood can be obtained from the animal (by injecting salt solution) then quickly open the chest by a median incision with tinner's snips and carefully excise the heart and lungs. Do not injure the vessels or tissues of the heart and Avatch that the auricles are not cut away. The aorta should be left an inch or more long. Cut off the lungs and free the heart as much as possible from fascia but do not tear the vessels. Tie all the large branches of the aorta, slip the main aortic trunk over the perfusion cannula (do R. Ventricle H./\urjcle Precava Brachiocephalic Art. R.Subdavian Art. R.CarotidM Postcava L.ventricle jj^/^a/f. LAurJcie Pulmonary vein LCarotid Art L.SubclavlanArt Aorta Ductus arteriosus Pultnonary Art Fig. 341. — Cat's heart. not insert the cannula far enough to interfere with the semilunar valves or the coronary arteries) and tie the can- nula in. Let the air all out of the perfusion tubes (by open- ing the outlet and running doAvn some of the perfusion fluid while the aorta just below the cannula is closed by a bull- dog). Remove the bull-dog and start the perfusion. Oxy- gen should be started to bubbling slowly through the stock solution. (Compressed air may be used instead of oxygen.) The temperature of the perfusion solution should be kept at about 39 degrees centigrade. The heart may not beat at first, but after a time the beats will begin and soon become PERFUSION OF THE HEART 427 strong and vigorous. Then take a normal record. Return the fluid which has already passed through the heart to the stock solution and prepare to inject some adrenaline with the hypodermic syringe through the wall of the rubber tube just above the heart. Two cubic centimeters of 1:10,000 solution may be injected slowly and steadily. How does this affect the record? How long does the action on the heart last! Do not return the solution into ivliich any drug Apex Vessels ^ faf in left or ventral ~^ loncjituclinal qroove ^Ricjhf ventricle Lef-t veniricle Left auricle — Posterior vena cava Pulmonary Veins Conus arteriosus Pulmonary Artery Riqht auricle Anterior vena cava Brachio- cephalic Art. Left Brachial Artery Li(famentum arteriosum Left Pulmonary Artery Fig. 342.— Dog's heart. has passed to the stock solution. Change beakers to catch the outflow as soon as the drug has all passed out. When the heart returns to normal inject some potassium chloride solution (one per cent) and get a record of the re- sult. Follow this with a solution of digitoxin (five cubic centimeters equal one milligram). Do not inject too much. How does this affect the heart? AYhen a satisfactory record has been obtained (give more digitoxin if necessary) then inject a second dose of potassium chloride and follow this 428 EXPERIME2TTAL PHARMACOLOGY with strophantliin (five cubic centimeters equal one milli- gram). How does this affect the heart ? Do you get satis- factory records? If the heart is in a suitable condition other drugs which may be tried are camphor, strychnine, pilocarpine, atropine, adonidin, calcium chloride, caffeine, chloroform, aiDomorphine, nicotine, cocaine, etc. It may be advisable to kill the heart with digitoxin. If this is done watch carefully to see if delirium cordis is produced and if so what chambers are first aifected. Also in what part of the cardiac cycle does the heart stop! Does it stop in systole or diastole in the intact animal? What explanation can you offer? What general conclusions can you draw from the experiment? What x)art do the coronary arteries and veins play in the experiment? What are the sinuses of Valsalva? AVhat is their function? Will the absence of intraventricular or intra-auricu]ar pressure in any way in- validate your observations? There are several other methods for studying the action of drugs on the isolated heart, e.g., those of Frank, Martin, Bock, Starling, Heymans and Kochman, etc. (See Heinz: Handbuch der Pathologie und Pharmakologie, i, 2, pp. 669 and 846 et seq.; also Sollmann: A Text-book of Pharmacol- ogy, 2nd edition, 1906, W. B. Saunders Co., pp. 895 and 953.) EXPERIMENT CXXXIII. Aconitine. (Frog: General Action.) 1. Destroy the cerebrum only of a frog, wait for the shock to wear off and then inject one cubic centimeter of aconitine solution (aconitine "potent," five cubic centi- meters ec[ual one milligram) into the dorsal lymph sac. Watch the symptoms carefully and see if there is any stimu- lation of the central nervous system. Are the muscles af- fected? What .general conclusions can you draw? ACTION OF ACONITIXE 429 EXPERIMENT CXXXIV. Aconitine. (Frog: Heart Tracing.) 1. Determine tlie action of aconitine on the heart and in- hibitory apparatus of a frog. Leave the meclidla intact. Inject the drug- into the dorsal lymph sac with a h^qoodermic syringe. The action on the heart is of some s^Decial interest because of the peculiar behavior of the organ under the ac- tion of the drug. This heart action has been thought to be of some value in identifying aconitine. What can you say regarding the chemical tests for the identification of aconi- tine? Do you know of any other drugs that act on the frog's heart in a manner similar to that of aconitine? EXPERIMENT CXXXV. Aconitine. (Turtle: Heart Tracing.) 1. Repeat the above experiment using a turtle instead of a frog. Apply the drug directly to the heart. What gen- eral conclusions can 3^ou draw? EXPERIMENT CXXXVI. Aconitine. (Dog: Blood-pressure, Respiration, Temperature.) 1. Arrange to record the blood-joressure, respiration and temperature (rectal thermometer). After the experiment starts make a record of the temperature reading every three or five minutes. Place aconitine solution (aconitine "potent," ten cubic centimeters equal one milligram) in the injecting burette. Isolate and ligate loosely [hut do not injure) both vagus nerves. When all is ready take a normal tracing and then inject one-half cubic centimeter of aconitine solution. Some samples of aconitine are exceed- 430 EXPERIMENTAL PHARMACOLOGY ingly poisonous and the doses must at first be small and guarded or the animal may be killed immediately and the details of the action of the drug cannot be made out. The object now is to give small, repeated injections and bring on the action of the drug very sloivly. If everything is working satisfactorily you should ob- serve after a time a slight slowing of the heart. This is manifested by" a gradual increase in the amplitude of the manometer tracing. The pressure will slowly become low- er. Do not crowd on the drug but wait patiently for the vagus center to be roused to greater and greater activity. Meanwhile the heart muscle is becoming slowly more and more irritable. But if the inhibitor}^ apparatus is normal it will at first get the upper hand and the heart should fi- nall}^ be greatly slowed. Is there any way by which you could prove that the heart slowing is due to stimulation of the vagus center? Continue the injections very cautiously and when the heart becomes noticeably slower then stop the in- jections and wait to see if the action of the drug does not become progressively more marked without further injec- tions. In some experiments the heart may become so slowed that the manometer tracing will show an amplitude of one-half to three-fourths of an inch for each separate heart beat. When this stage is approached then carefully lift up both vagus nerves and quickly cut them with the scissors. What effect has this on the blood-pressure and heart beat? Caution: Do not mistake the carotid artery and cut it instead of one vagus nerve as the author has seen a student do. What would you do if this accident occurred ? Wait a while now and see if the action of the drug de- velops further without giving any more of the poison. How does the heart beat? Can you determine the true action of the heart by watching the mercury manometer? Does the pressure become exceedingly irregular? It should do so and then after a longer or shorter period (usually only a ACTION OF ACONITINE 431 few iiiiniites) the heart suddenly goes into delirium cordis and the pressure quickly falls to zero. It may be necessary to give a little more of the drug to produce the final effects within a sufficiently short time. How did section of the vagi affect the respiration! What was the very first abnormal action which your animal showed as seen in your tracing? Examine the respiratory record closely. What general conclusions can you draw? If the vagi had not been cut what Avould have happened to the heart! If two or more experiments are performed at the same time one group of students should cut the vagi, a second group should give one milligram of atropine and a third should let the action of the aconitine proceed without interfering in any way. Immediately after the animal dies open the chest quickly and see if the heart is fibrillating. EXPERIMENT CXXXVII. Aconitine. (Dog: Heart Tracing's, Blood-pressure.) 1. As in Experiment CXXX under cligitoxin, arrange to record blood-pressure and heart tracings from a dog. Place aconitine solution (ten cubic centimeters equal one milli- gram) in the burette. AVhen a normal record has been taken then very slowly and cautiously inject small repeated doses of aconitine. The object is to bring on the action very slowly and to let each phase of the heart reaction be fully developed. Watch the chambers of the heart and see which ones first show ab- normalities. Over what chambers of the heart do the vagus nerves exercise the fullest control! Can you see any evi- dence of this by watching the heart as the action of the drug comes on? Do you get the stage of marked slowing as in the previous experiment! Do the two auricles beat together or in dif- ferent rhythm! Is this true for the ventricles also ! Does 432 EXPERIMENTAL PHARMACOLOGY /o^^A rm\ Fig. 343. — Tracing showing the final action of aconitine on the heart (myocardiogram, right auricle and right ventricle) and blood-pressure in a dog. The contractions are very- fast and irregular. ACONITINE AND VERATPJNE 433 this hold ill the case of the frog? Watch for the sudden ap- pearance of irregular heart heats, extra sj'stoles, etc. In what chainbers are these first developed? Can 3^ou get satisfactory records of the heart movements when the rate is exceedingly fast? Watch for the sudden development of delirium cordis. What happens to the blood-pressure ■when this occurs ? After the heart begins to fibrillate stimu- late the vagi and see if you can stop the fibrillation. What conclusions can you draw? Feel of the heart and describe the nature of the fibrillary contractions. EXPERIMENT CXXXVIIT. Aconitine. (Student: Local Action.) 1. Saturate a piece of filter paper one-fourth inch square with a solution of aconitine (ten cubic centimeters equal one milligram) and place the filter paper on the tongue. Do not swallow any of the solution. After a little while re- move the paper and note the sensation produced on the tongue. What conclusions can you draw? (If the solution was too weak a stronger one may be used.) EXPERIMENT CXXXIX. Veratrine. (Frog: General Action.) 1. Destroy the cerebrum only of a frog, wait for the shock to disappear and then inject one cubic centimeter of vera- trine sulphate solution (ten cubic centimeters equal one milligram) into the dorsal lymph sac. Place the animal on a table and wait a little while for the drug to be absorbed. From time to time touch the animal gently and get it to jump. Do you notice anything unusual about its move- ments? Does it have trouble in extending or relaxing its muscles? Does it have spontaneous convulsions? Examine the skin to see if there is an increased cutaneous secre- 434 EXPERIMENTAL PHARMACOLOGY tioii. The animal after a time will be able to jmiip very well but will alight with the hind legs extended and the fore legs passed back along the flanks. Only with difficulty can the animal then draw up its hind limbs. What is the cause of this difficulty! After some time (if the dose was large enough) the animal becomes completely paralyzed and dies. Then expose the heart and note whether it stopped in systole or diastole. In what condition does the heart usu- ally stop ! Is this true for a mammal also ? What can you say of the general action of veratrine '? EXPERIMENT CXL. Veratrine. (Frog or Turtle: Heart and Inhibitory Apparatus.) 1. Arrange a frog or turtle for taking heart tracings. Make a normal record (showing both vagus trunk and cres- cent inhibition). Pour a few drops of veratrine (sulphate or hydrochloride) solution (ten cubic centimeters equal one milligram) on the heart and record the effect. After the drug has acted a few moments stimulate the vagus nerve again and see if the heart is inhibited. Also stimulate the crescent and see what happens. What conclusions can you draw? Apply more of the drug and record the full action on the heart. Is there any visible difference between the action on the ventricle and that on the auricles? Would your method of suspension obscure the appearance of the behavior of the heart under the drug ? EXPERIMENT CXLI. Veratrine. (Frog: Skeletal Muscle.) 1. Set up your apparatus as shown in Experiment XL VII, p. 245 (see also Experiment XCVI under cocaine), for re- cording muscular contractions. Then pith a frog and ligate ACTION OF YERATRIXE 435 the left thigh tightly. Under the skin of the back inject two cubic centimeters of veratrine solution (five cubic centi- meters equal one milligram) and attach the animal to the frog board as illustrated. Connect the secondary wires to the tendo Achillis and to the carpet tack. Do not stimulate the muscle as the first contraction is the one which will in ^(^^ti^ ^^e.t(le^/t>»«'toi^i''^'T^. Fig. 344. — Frog heart tracing showing the action of veratrine. The vagus trunlc was stimulated as indicated. Inhibition occurred before but not after veratrine was applied. What action did the drug have here? How would you prove your conclusions? all likelihood shoAv the action of the drug the best and this one should be recorded. Adjust the inductorium connec- tions for single shocks and use only the hreak shock to stimulate the muscle. About ten or fifteen minutes should be allowed for absorption of the drug. AVhen everything is entireli) ready start the drum (medium speed) and when 436 EXPEEIMENTAL PHARMACOLOGY the muscle lever has recorded a line half an inch long (be sure the lever is properly weighted and adjusted) stimulate the muscle with one single shock. The muscle should con- tract quickly but the relaxation is much prolonged and usually shows certain peculiarities. Let the drum run and Fig. 345. — Arrangement of apparatus for spinning tlie drum a single round at a time and stimulating a muscle or nerve with a single shock during the revolution of the drum. (See Jour. Amer. Med. Assoc, 1911, 56, 1705.) record the full relaxation but as soon as the lever again reaches the base line stimulate the muscle again mth one single shock. Eecord this contraction and when the lever again comes down to the base line repeat the stimulation. A series of contractions will thus be secured. The charac- ACTIOi^ 01' YERATPJNE 437 ter of these contractions clianges rapidly Avitli eacli sncceed- ing- curve until a perfectly normal record may he secured. Exj)lain the nature of this change in the contraction curves. AVhy are there undulations at the top of the curves ? What effect has fatigue on the action of the drug f Let the muscle rest a while and see if you can get a second series like the first. Now take a few contraction records from the normal (left) gastrocnemius muscle to compare with the curves showing the drug action. EXPERIMENT CXLII. Veratrine. (Turtle: Lung Tracing.) 1. Arrange a turtle for recording lung tracings. Inject two cubic centimeters of veratrine solution (ten cubic centi- meters equal one milligram) into the ventricle and note the action on the lungs. If this does not give 3^ou a record then pour some of the solution over the lungs (local application). Do you get a record I If so on what structures did the drug act to produce the result? (It is very acMsable to remove all the intestines, liver and bladder and as much as possible of the skeletal muscles from the turtle before making a test on the lungs, for sometimes the skeletal muscles suddenly contract and obscure the results. The cord should also be thoroughly pithed. One can then look at the lungs closely and see if they contract.) EXPERIMENT CXLIII. Veratrine, Adrenaline. (Dog: Blood-pressure, Respiration, Intestinal Contraction.) 1. Arrange a dog for recording blood-pressure, respira- tion and intestinal contractions. The burettes contain verat- rine (ten cubic centimeters equal one milligram) and adrenaline (1:10,000). 438 EXPERIMENTAL PHARMACOLOGY ACTIOIs^ OF veratrijs:e 439 AVlien all adjustments are made take a normal and in- ject one cubic centimeter of veratrine solution. Do you get an intestinal record? The dose was probably too small but the toxicit}^ of commercial preparations varies greatly and some samples are exceedingly poisonous. AVhen once you have determined the dose which your animal can withstand then inject a larger amount and watch for intestinal con- tractions. (One group of students should also record the bladder contractions.) The respiration should be affected rather earh^ Watch for the heart to become slower. This will be seen in the increased amplitude of the manometer tracings. The action of the drug should now be brought on slowly as with aconitine and digitoxin. This is the best way to bring out the central vagal stimulation which slows the heart. The beating of the heart should finally become very slow and the amplitude of each beat as recorded by the manometer may reach half an inch or more in length. If you succeed in getting this action then suddenly cut both vagus nerves and see if the heart accelerates as after aconi- tine. Does veratrine make the heart more irritable! Do you get a stage of irregular heart beats as occurs Avith aconitine f Kill the animal by repeated injections of the drug. What general conclusions can you draw from the experiment? If another group of students are performing the experiment at the same time then one group can give the animal an injection of one cubic centimeter of atropine (one cubic centimeter equals one milligram) instead of cut- ting the vagus nerves. A third group may let the veratrine take its regular course of action, neither cutting the vagi nor giving atropine. The groups can compare their results. Examine your respiratory record closely and see whether any indications of a Cheyne-Stokes type of lu'eathing are present. Is the respiratory disturbance due to a central or a peripheral action ! 440 EXPEEIMENTAL PHARMACOLOGY EXPERIMENT CXLIV. Veratrine. (Dog: Heart Tracings, Blood-pressure.) 1. Record heart tracings from a dog showing the action of veratrine. Proceed as in Experiment CXXXVII, p. 431^ or Experiment CXXX, p. 418. (Cardiometer tracings, from the ventricles, may also be recorded in another animal.) EXPERIMENT CXLV. Apomorphine. (Dog: Vomiting Center.) 1. Inject snbcutaneonsly into a dog (eight to ten kilos) one or two cnbic centimeters of apomorphine hydrochloride (one cnbic centimeter eqnals five milligrams). Leave the animal in a cpiiet place and observe its actions from time to time for three or fonr lionrs. Is there any noticeable action on the cerebrnm or cerebellnmf What general symptoms are prodnced? What conclnsions can yon draw from the experiment! Are the pnpils affected! Is there salivation! If so how do you explain it! EXPERIMENT CXLVI. Ipecac. (Dog: Emesis.) 1. Administer by stomach to a dog (eight to ten kilos) three cnbic centimeters of the flnid extract of ipecacuanha. Leave the animal in a cpiiet place and observe its actions from time to time for three or four hours. What general symptoms are produced! What conclusions can you draw from the experiment! What are the chief differences be- tAveen the actions of apomorphine and ipecac! ACTION OF CYAiSriDi:S 441 EXPERIMENT CXLVII. Sodium Cyanide, (Hydrocyanic Acid), Sodium Sulphide, Hydrogen Peroxide. (Dog: Respiration, Blood-pres- sure, Oxygen Consumption, Blood, Glycosuria.) 1. Arrange a dog (give a small dose of cliloretone) for recording hlood-pressure, respiration, and oxygen con- sumjDtion. The injecting burettes contain either sodium cyanide (one-half per cent) or hydrocyanic acid (one-half per cent — the official form is supposed to be two per cent^ but is usually much weaker and often unreliable) and so- dium sulphide (one per cent). When all adjustments are made take a normal record showing at least one or two notches for the oxygen con- sumption tracing. Then inject one-half cubic centimeter of the cyanide solution. Marked results should be shown on all three tracings. The dose may be too small if 3^our drug was deteriorated (as is very often the case — ouly fresh preparations should be used). Very small doses of the cyanides do not affect, or possibly, may even slightly in- crease the rate of oxygen consumption. Large doses de- crease the rate and your records should easily show this action. When the animal returns to normal again inject a dose (perhaps one cubic centimeter) of cyanide and note the ef- fect. Get the oxygen consumption record over three or four notches to see the prolonged action of the drug on this function. Let the animal recover and give a third injection of cyanide. When the symptoms become marked inject one cubic centimeter of the sodium sulphide solution (sodium liyposulphite may be substituted) and determine Avliether or not this aids materially in the recovery of the animal. What antidotes do you know for cyanide poisoning? How are these administered! How quickly could tbis be done? Hov.' quickly will the cyanide act ? 442 EXPEEIMENTAL PHARMACOLOGY Fig. 347. — Tracing showing the action of sodium cyanide on the rate of oxygen con- sumption, blood-pressure and respiration of a dog. Oxygen was given in ISO c.c. quantities at a time. ACTION OF CYANIDES 443 Allow the animal to recover and watch carefully for the appearance of an irregular form of respiration. Cheyne- Stokes respiration is often produced by cyanides. Inject some more sodium sulphide after a time to see how the drug acts then. How does the sulphide affect the oxygen consumption ? Fig. 348. — Tracing showing the action of potassium cyanide on the blood-pressure and respiration of a dog anesthetized with nitrous oxide. If the animal is still in fair condition (as it probably is) insert a straight cannula into one femoral artery and draw off five cubic centimeters of blood into a test tube. Then pour one cubic centimeter of your cyanide solution into the blood, shake up the mixture and examine its color closely. 444 EXPERIMENTAL PHAEMACOLOGY r- C ACTION OF CYANIDES 445 Set the tube aside and see whether or not clotting occurs. What action have cyanides on the coagulation of blood! How is this brought about? Draw off another five cubic centimeters of blood and i-i'A,iii^^ X miuMu Fig. 350. — Myocardiogi-arhic and biood-pressure tracings showing tlie action of 2 c.c. of a dilute sodinm cyanide solution. 446 EXPERIMENTAL PHARMACOLOGY then pour a few drops of hydrogen peroxide into the test tube. What happens when the peroxide mixes with the blood? Is the color of the blood changed? Now draw off another five cubic centimeters of blood and pour two cubic centimeters of cyanide solution into the test tube. Shake up the mixture and then add hydrogen peroxide to the test tube. Do you get any frothing of the mixture? Why? Does the solution remain bright red? How do you explain this? Save the test tubes and examine each (in one-half cr one per cent solution) spectroscopically (if you have a spectroscope) after the animal dies. A tube of normal blood to which a little (one per cent) sodium citrate solution has been added may also be saved for comparing the spectra of the different samples. Now pass a catheter into the bladder (if you can) and draAv off some urine. If you cannot pass the catheter, open the abdomen, isolate the bladder, and insert a large hypo- dermic needle through the bladder wall and draw off some urine. Test this urine with Fehling's or Haine's solution for sugar. If you get a positive test, how do you explain the cause of the glycosuria ? What factors are involved and what is the mechanism of their action? Do you know of any other drugs that have a similar action? Give a large dose of cyanide and as soon as the respiration stops start artificial respiration to see if you can revive the animal. This is often successful when the dose is not too large. Re- covery usually occurs fairly rapidly if the dose is of moderate size. Kill the animal with cyanide. What is the size of the fatal dose ? How does this compare with aconi- tine or strychnine ? Discuss in full your observations on the blood-pressure, cardiac inhibition, nutrition, treatment, res- piration and coagulation of the blood. It will be instructive to keep the dead animal for a few hours to see if the blood clots in the vessels. The color of the blood should also be noted after a few hours. Is rigor mortis hastened or delayed in its appearance? ACTiox OF quininp: 447 EXPERIMENT CXLVIIT. Quinine. (Frog: General Symptoms.) 1. Destroy the cerebrum of a frog and inject into the anterior lymph sac one cubic centimeter of quinine hydro- chloride solution (one cubic centimeter equals ten milli- grams). Put tlie frog in a quiet place, count the rate of lymph heart beats and of the heart beats. Observe the ani- mal carefully as the action of the drug comes on. Are there any signs of central nervous stimulation f How is the rate of beat of the heart and of the lymph hearts affected! Do the reflexes persist? Can you elicit a pupillary light re- flex ? Save the animal to see if it survives the action of the drug? What conclusions can you draw from the experi- ment ? EXPERIMENT CXLIX. Quinine. (Frog or Turtle: Heart Tracing.) 1. Arrange a frog or turtle for taking heart tracings. Make a normal record showing vagus stimulation. Then irrigate the heart with quinine hydrochloride solution (one cubic centimeter equals ten milligrams). What effect has the drug on the heart muscle and on the nervous inhibitory apparatus 1 EXPERIMENT CL. Quinine. (Frog: Action on White Corpuscles — Binz's Experiment.) 1. Pith a frog and make a longitudinal incision in one side of the abdomen. Carefully pull a loop of intestine {leaving the mesentery intact) out through the incision. Place the frog on a thin board similar to that illustrated in Fig. 305, but which lias a circular hole about one inch in 448 EXPERIMEISTTAL PHARMACOLOGY diameter in the side nearest the microscope. This hole should be near the middle of the length of the board and about one-fourth inch from the side of the board (next to the microscope). A cork is passed into the hole (tightly) and then a second hole about one -half inch in diameter is bored through the cork so that the mesentery of the frog can be stretched out over the hole in the cork and thus brought under the objective of the microscope. Pin down the loop of the intestine to the upper surface of the cork and thus secure a flat surface of the mesentery for observations. The upper surface of the cork should be about one-fourth inch above the surface of the board. Use the low power ob- jective and observe the blood flow through the mesenteric capillaries. Examine the white corpuscles carefully. Ob- serve how they move along next to the capillary walls or pass out slowly into the tissues. Do you see any lympho- cytes? The exposure and manipulation of the tissues of the mesentery will produce sufficient inflammation to cause an accumulation of leucocytes in the area involved. After you have fully familiarized yourself with the appearance and action of these leucocytes then inject into the anterior lymph sac of the animal two cubic centimeters of quinine hydro- chloride solution (one cubic centimeter equals ten milli- grams) and watch the actions and distribution of the leu- cocytes as the drug is absorbed. Do the white corpuscles still cling to the lining of the vessels, or do they pass out into the neighboring tissues'? What conclusions can you draw! What relation does the action of the quinine on the white corpuscles bear to the action of quinine on the Plas- modium of malarial fever! What general conclusions can you draw from the experiment! Quinine is often injected intravenously in severe cases of malarial infection in man. This form of treatment is effec- tive, and rapid results ma^'' be obtained. From the above experiment what action do you infer the quinine thus thrown rapidly into the blood will have on malarial organisms (pro- vided the concentration of the drug is great enough) ! ANTIPYRINE AND /?-TETRAHYDROISrAPHTHYLAMINE 449 EXPERIMENT CLl. Antipyrine. (Frog: General Action.) 1. Into the anterior lymph sac of a frog inject two cubic centimeters of antipyrine solution (one cuhic centimeter equals ten milligrams). Put the frog in a quiet place and observe its actions closely. Are the reflexes stimulated or depressed! Is there developed somnolence or convulsions? How is the central nervous system atfected? EXPERIMENT CLII. Antipyrine, /3-tetrahydronaphthylamine Hydrochloride. (Dog: Respiration, Blood-pressure, Leg Volume.) 1. Arrange a dog for recording blood-j)ressure, respira- tion and the volume changes of the left hind leg (plethys- mograph). Take the animal's temperature at ten minute intervals. Place antipyrine solution (one cubic centimeter ecpials ten milligrams) and j8-tetrahydronaphtliylamine hy- drochloride (one cubic centimeter equals live milligrams) in the two injecting burettes (in the right femoral and left external jugular veins). Take a normal record and then inject one cubic centi- meter of antipyrine. How is the heart affected! The res- piration? Do you get a change in leg volume? If so what does this signify? Wait for the animal to return to normal. Inject two cubic centimeters of /^-tetrahydronaphthjda- mine solution (watch the pupils and eyelids closely as this is done). Do you get a change in leg volume? (The rub- ber cuff must fit tightly to the skin of the leg which must be shaven closely — you cannot make the cuff hold air if the hair is left on the leg. Avoid vaseline for this purpose.) How does the action of the /?-tetrahydronaplitliylamine com- pare with that of antii^yrine on the blood-pressure, res- Xjiration, temperature controlling mechanism and leg vol- 450 EXPERIMENTAL PHARMACOLOGY ume? Is it possible to determine the action of such drugs as antipyrine or /S-tetrahydronaphthylamine on the heat regulating mechanism in a brief interval of time, e. g., in ten minutes? On what do you base your conclusions? From time to time inject more antipyrine and see what later actions the drug has. Further injections of jS-tetra- Fig. 351. — Tracing showinor the action of pilocaroine and j8-tetrahydronaphthylamine hydro- chloride on the bronchioles and blood-pressure in a spinal dog. hydronaphthjdamine may also be made to get satisfactory tracings. Kill the animal with antipyrine. A¥hat s^anptoms are produced and what is the immediate cause of death ? iS-tetrahydronaphthylamine belongs to a class of drugs to which the name ''sympatho-mimetic" has been applied. Adrenaline is the best known member of this group. These drugs act on one or more parts of the involuntary nervous system (see Fig. 318). ANTIPYRETICS 451 EXPERIMENT CLIII. Antipyrine, Peptone. (Two Rabbits: Temperature Regulation.) 1. Four hours before the class meets administer hypo- dermically to each of two rabbits (one for a control) one- tenth of a gram per kilogram of weight of Witte's peptone (in twenty per cent solution). Record the temperature of both rabbits and then give one by stomach one-tenth gram per kilogram of w^eight of antipyrine. Record the tem- perature of each animal at fifteen minute intervals, and de- termine whether or not the temperature is affected by the antipyrine. EXPERIMENT CLIV. Quinine, Peptone. (Two Rabbits: Temperature Regulation.) 1. Repeat the above experiment but substitute quinine hydrochloride (one-tenth gram per kilo) for the antipy- rine. Does this affect the temperature in any Avay? Dis- cuss the manner of action of antipyrine and of quinine on the heat regulating meclianism and on the reduction of fever temperature. EXPERIMENT CLV. Phenacetine, Acetanilide or Aspirin (Acetylsalicylic Acid). (Fevered Animal: Temperature.) 1. Watch the stock of animals during the period when the antipyretics are being studied and if an animal be- comes ill with a rise in temperature then administer to it by stomach one-tenth gram per kilogram of weight of phe- nacetine, acetanilide, or aspirin. Record the temperature at fifteen minute intervals and see if any change occurs. 452 EXPERIMENTAL PHARMACOLOGY How long will it probably be before the fever returns if the drug lowers the temperature to normal? Which of these three drugs is most effective in lowering the temperature? EXPERIMENT CLVI. Acetylsalicylic Acid (Aspirin). (Student: Headache.) 1. Watch for a student or other person who has a head- ache due presumably to "migraine." Consult the instruc- tor and if the person affected with the headache is other- wise normal give him by stomach a five grain tablet of acetylsalicylic acid. Observe the action of the drug and see if the headache is not decreased in about fifteen or twenty minutes. The drug, in reasonable doses, is not dan- gerous and often entirely stops certain types of headache. Mter half an hour another five grain tablet may be taken if absolutely necessary. Do you know of any other drugs that might be used here instead of the acetylsalicylic acid ? If so what sized doses should be given? EXPERIMENT CLVII. Phenylsalicylate (Salol). (Student: Excretion, Absorption.) 1. Take by mouth a capsule containing five grains of salol. This is decomposed, on reaching the intestine, into phenol and salicylic acid. Test the urine for salicylic acid by adding a few drops of ferric chloride when a violet color- ation appears. A positive test should be observed in one to one and one-half hours. This is Ewald's test for the motility of the stomach but a dose as large as one gram has been recommended for this purpose. The U.S.P. dose is five grains. (For literature, see Hanzlik, P. J.: Reports of Therapeutic Research Committee, A. M. A., 1914, 3, 131.) iS-TETRAHYDEONAPHTHYLAMlNE AND PILOCARPIJSTE 453 EXPERIMENT CLVIII. /?-tetrahydronaphthylamine Hydrochloride, Pilocarpine. (Dog: Oxygen Consumption, Blood-pressure, Respiration.) 1. Arrange a dog (eiglit or ten kilos) for recording oxy- gen consumption, blood-pressure and respiration. (Give a small dose of cliloretone.) The injecting burettes contain )5-tetrahYdronaplithylamine hjTlrochloride (one cubic cen- timeter equals five milligrams) and pilocarpine (one cubic centimeter equals one milligram.) When all adjustments are made take a normal record (showing at least two notches of the oxygen record). Then inject tAvo cubic centimeters of the /?-tetrahydronaplitliyla- mine (watch the pupils) and record the results. How is the rate of oxygen consumption affected? Wait for the drug to act and see if all records return again to normal. Then give one cubic centimeter of pilocarpine. Watch the rate and depth of the respiratory movements as the drug begins to act and wait a little while for this to develop. The action of pilocarpine is rather prolonged and may in- crease in intensity for about one minute, or in some organs for even a longer period. Is there any difficulty in either expiration or inspiration? What did the oxygen record show just after the pilocarpine was injected? How do you account for this? What kind of an effect on the oxygen record Avould a drug show if it acted in a manner exactly the opposite to that of pilocarpine ? When the pilocarpine action becomes well marked (give another one cubic centimeter if absolutely necessary) then inject a dose (probably three or four cubic centimeters of iS-tetrahydronaphthylamine — estimate a good sized dose by your previous result) and see how this drug counteracts the pilocarpine. How is the oxygen record affected? How do you account for this? Do you know of any other drug that resembles jS-tetrahydronaphthylamine in action? 454 EXPERIMEN^TAL PHARMACOLOGY Record the temperature of the animal from time to time and see if you can produce a hyperthermia by injecting /?-tetrahydronaphthylamine. Will the narcosis prevent this rise in temperature in your animal ? How does the drug act to produce a fever temperature! Kill the animal by injecting /8-tetrahydronaphthylamine. After death test the urine for reducing bodies. What conclusions can you draw from the experiment! Are the adrenal glands espe- cially involved in any wa^^ in this exi^eriment ! If so, how ? Are there any other drugs that have this action! EXPERIMENT CLIX. Carbolic Acid (Phenol). (Frog: General Action.) 1. Into the anterior lymph sac of a frog inject one cubic centimeter of a one per cent solution of carbolic acid. Put the frog in a quiet place and observe its symptoms. Do you note depression or are there convulsions! What struc- tures are involved in the action of the drug! EXPERIMENT CLX. Carbolic Acid, Sodium Sulphate. (Dog: Local Action, Respiration, Blood-pressure, Spleen Volume, Antidote.) 1. Arrange a dog for recording blood-pressure, respira- tion and the volume changes of the spleen. The injecting burettes contain carbolic acid (one-half per cent) and so- dium sulphate (three per cent). With a razor shave the hair off of a spot on the dog an inch or more in diameter. In the center of this spot put a drop of phenol liquef actum (U.S.P. about 90 per cent — make this from the crystals by adding a very little water to some of the substance in a test tube and heating gently till solution is effected. How does this preparation differ from CARBOLIC ACID 455 Fig. 352.— Two tracings (joined together) showing the action of a drug which markedly lowers blood-pressure, on the intestinal volume, spleen volume, blood-pressure and respiration. See if you can find a drug which produces this kind of a tracing and determine the difference between active and passive effects on oncometer tracings. 456 EXPERIMENTAL PHARMACOLOGY a simple solution of the crystals in water f Only about five per cent of the drug can be dissolved in water.) Watch the action of the drug on the skin closely, noting color changes, etc. After a short time wipe off the phenol and see what kind of a scar is left. Quickly sponge 95 per cent alcohol thoroughly over the spot and see how the color and appearance of the area are affected. Of what practical use may this be to you 1 What antidote would you apply if carbolic acid had been swallowed 1 In Avhat strength would you use the antidote and what precautions would you take to prevent its absorption? Proceed quickly with the ex- periment. When all adjustments are made take a normal record and inject five cubic centimeters of carbolic acid solution. A¥ait for the drug to act. When the records return to nor- mal again inject five cubic centimeters of the phenol solu- tion. What differences do you note between the effects produced by the two injections? After a time inject more of the phenol and bring on a marked reaction (be sure the sodium sulphate is ready and that the injecting cannula is not closed off by a clot). When the animal is greatly de- pressed note its condition (muscular twitchings, etc.) closely and begin to inject the sulphate solution (in two cubic centimeter doses frequently repeated). What effect has this on the animal? How do you explain the result? See if you can get the animal to return to normal. After a time stimulate one vagus nerve and see if the heart is inhibited. Does this affect the respiration? Now take a very small pledget of cotton, soak it in phenol lique- factum and place it on the vagus trunk for one minute. Remove the cotton and stimulate above the poisoned area. Repeat the stimulation below the area. How does each stimulation affect the heart and respiration? What con- clusions can you draw ? With a stomach tube inject fifty cubic centimeters of five per cent carbolic acid into the dog's stomach and wait PHLORIDZIjST, ADREiSrALINE, POTASSIUM IODIDE 457 for the animal to die. After death pass a trocar into tlie bladder (or catheterize) and draw off some urine. Test this for albmnen (nitric acid test) and for reducing bodies (Fehling's test). Put five cubic centimeters of urine in a test tube and add a few drops of ferric chloride solution. If you get a color reaction what does it mean? Put some of the urine in a beaker and set it aside until next day to observe any later changes in color. Open the stomach care- fully (over a sink) and examine closely the condition of the gastric mucosa. What would the stomach lining show if sectioned and examined histologically? Do this if you can. What conclusions can you draw? How is carbolic acid excreted ? What is the fate of the drug in the tissues ? (See Sollmann, Brown, Clarke: Journal American Medical Association, 1906, March 17, and 1907, March 23 ; also Jour- nal of Pharmacology, i, p. 409.) EXPEEIMENT CLXI. Phloridzin, Adrenaline. (Rabbit: Glycosuria.) 1. Dissolve one-fourth gram of phloridzin in warm water, and inject it subcutaneously into a rabbit. Obtain a sam- ple of the urine at the end of two hours, by pressure on the abdomen with the thumb or by passing a catheter, and test for sugar. If none is present wait some time longer and again test the urine (Stewart). Glycosuria may also be produced by injecting subcutaneously into a rabbit one or two cubic centimeters of adrenaline (1:1000). The rab- bits should be placed in a cage where the urine can be col- lected. EXPEEIMENT CLXII. Potassium Iodide. (Student: Absorption, Excretion.) 1. Take by mouth a capsule containing five grains of potassium iodide. (Iodides have to be used with care in cases of pulmonary phthisis.) 458 EXPERIMEI^TAL PHARMACOLOGY At one minute intervals after the drug is swallowed test the saliva (on a white pill tile or glass plate on a sheet of paper) by adding saliva to three per cent starch paste (slightly acidified by HNO3). A positive test should ap- pear within ten to fifteen minutes if absorption be normal. Test the urine by adding a few drops of chlorine water and starch solution. What conclusions can you draw ? EXPERIMENT CLXIII. Alkalies, Acids, Sodium Nitrite, Adrenaline. (Frog: Per- fusion of Vessels.) 1. Pith a frog, expose its heart and tie a fine cannula into one aorta (pointing away from the heart) including the other aorta in the ligature. Hang the frog up by the lower jaw and place a graduated cylinder beneath the animal. By means of a Y-tube connect two funnels (or small bottles with outlets at the bottom) to the cannula in the aorta. Suspend the funnels or bottles at a height of six or seven inches above the heart. One funnel (or bottle) is filled with NaOH solution (one-tenth per cent in Ringer's or tapwater saline solution) and the other with HCl solution (one-tenth per cent in Ringer's or tapwater saline solution). Snip the sinus venosus so that the fluid can pass through the entire system of blood vessels from the beginning of the aorta. Be sure all the air is out of the tulles and that the flow of each solution can be stopped or started b}^ means of clips on the connecting tubes. Fill the tubes with the acid solution and start the perfusion. Catch the outflow below the frog in the graduated cylinder and determine its amount for three or five minute intervals. Then change to the alkali solution and measure the out- flow for a corresponding length of time. Which substance dilates the arterioles? Empty out the acid solution and substitute therefor Ringer's solution containing one-half per cent sodium ni- PERFUSION OF FROG 's VESSELS 459 trite. Perfuse tliis tliroiigli tlie vessels of tlie animal and see how the outflow is affected. Empty the alkali solution and place Ringer's solution in the funnel (or bottle) and add one-half cubic centimeter of adrenaline solution Fig. 353. — Arrangement of apparatus for perfusion of the vessels of a brainless frog. 460 EXPERIMENTAL PHARMACOLOGY (1:1000) to the Einger's solution. Perfuse this solution through the animal and compare the outflow with that from the other solutions. What conclusions can you draw f How do acids and alkalies compare with adrenaline and nitrites as regards their effects on the arterioles? EXPERIMENT CLXIV. Magnesium, Calcium. (Rabbit: Anesthesia, Antagonism. — Meltzer and Auer.) 1. Into a rabbit inject subcutaneously 1.7 grams of mag- nesium sulphate (in twenty-five per cent solution) per kilo- gram of weight. Watch the animal closely and observe that in thirty or fort}^ minutes deep anesthesia is produced. A ten cubic centimeter hypodermic syringe with a very fine point is now filled with three per cent calcium chloride solution. Place a bull-dog on the lateral margin of the rabbit's ear near the head and block the flow of blood in the marginal ear vein which will become engorged with blood. Insert the syringe point into the vein (pointing to- ward the heart), remove the bull-dog and inject about eight cubic centimeters of the calcium chloride solution. Handle the animal carefully and observe what effect the calcium has. What conclusions can you draw? What explanation can you offer? Could you use magnesium chloride instead of the sulphate? Would it simplify the conditions if cor- responding salts (chloride) of the metals were used? EXPERIMENT CLXV. Arsenic. (Dog or Rabbit: Respiration, Blood-pressure, Peristalsis, Renal Action, Blood.) 1. Prepare a dog (or rabbit — two grams of ure thane) for recording blood-pressure, respiration and intestinal con- tractions. Insert a bladder cannula (avoid hemorrhage into ACTION OF ARSEN-IC 461 tlie bladder) or pass a catheter and draw off all the urine in the bladder. Test this for glucose, albumen and casts (centrifuge and use the precipitate for microscopic observa- tions). The injecting burette contains sodium arsenate so- lution (one per cent). Draw off one cubic centimeter of blood from the femoral artery and add to it one-half cubic centimeter of one per cent copper sulphate solution. Draw off another cubic cen- timeter of blood and add to it one-half cubic centimeter of sodium arsenate solution (one per cent). Shake up both tubes and observe them carefully. What conclusions can you draw? Of what immediate importance is this to you? When all adjustments are made take a normal, record the time of day and inject one cubic centimeter of arsenic solution. How are the blood-pressure and respiration af- fected! Wait a while and then inject another cubic centi- meter. How does the reaction to this dose correspond with that produced by the first dose ? Continue the injections (small) slowly and allow the drug to be fully distributed to all the tissues. The drug should act for a long time (several hours) to produce the most marked lesions. Keep the animal alive as long as you can and from time to time inject as much of the arsenic as the animal will tolerate. Obtain specimens of urine occa- sionally and test for albumen and for reduction of Fehling's solution. Do you detect any indications of an action on the alimentary tract ? How does the drug act here ! What renal structures are especially affected by the substance? Near the end of the exercise kill the animal with the drug. Test the urine for albumen, glucose, and casts. Are there any blood cells in the urine (centrifuge and put a drop of the sediment on a slide, cover with a cover slip and examine microscopically) ? Open the abdomen, pick up the small intestine and incise it longitudinally. What is the nature of the contents? Examine tlie mucosa care- fully for congestion and hemorrhages. Save a piece of the 462 EXPERIMENTAL PHARMACOLOGY intestine and examine it histologically for changes in the mucosa, etc. Is the stomach similarly affected? How did the drug reach these organs! Excise one kidney, preserve and section it for microscopic examination. Examine the liver, lungs, spleen, mesentery, etc., and see if 3^ou can de- tect any abnormal changes in them. What general con- clusions can you draw from the experiment? EXPEETMENT CLXVI. Antimony (Tartar Emetic). (Dog: Emesis.) 1. Stir up forty to fifty milligrams of tartar emetic ( Anti- monii et Potassii Tartras) in thirty cuIdIc centimeters of water and administer through a stomach tube to a dog. Put the animal in a quiet place and observe its symptoms for half an hour. What conclusions can you draw? Ex- plain in detail the action of the drug. Do you know of any other substance having a similai' action? EXPERIMENT CLXVII. Vanadium, Sodium Hydroxide, Ammonia. (Dog: Blood- pressure, Respiration, Spleen Volume, Reflex and Local Actions, Intestinal or Bladder Contractions.) 1. Arrange a dog for recording blood-pressure, respira- tion, spleen (or kidney) volume and intestinal or bladder contractions. Do not insert a tracheal cannnla at first hut carry on the anesthesia by dropping ether on a toivel wrapped around the dog's nose and mouth. The injecting burettes contain ammonium chloride solution (two per cent) and sodium ortlio vanadate solution (one per cent, — dissolve the vanadium in water and neutralize with a small amount of hydrochloric acid. .A deep golden yellow solution is pro- duced). ACTION OF VANADIUM Fig. 354. — Tracing showing the action of adrenaline sodium orthovanadate, amyl nitrite and adrenaline on the kidney volume, leg volume (hind limb), blood-pressure and respiration of a dog. The first injection of vanadium usually produces a more marked reaction than those following. 464 EXPERIMEE^TAL PHARMACOLOGY When all adjustments are made take a normal record and then pour a few drops of ammonium hydroxide solu- tion on the towel so that the animal inhales the vapors. How does this affect the respiration, bladder, spleen vol- ume and heart rate? How do you explain the results? What nerves are involved in the reactions? Remove the ammonia and insert a tracheal cannula. /OjSju:^JA, Lever onia-tnloour bowl. Fig. 355. — Tracing showing the action of vanadium on the volume of an excised, perfused segment of the small intestine of a dog. Take a normal record and then inject one cubic centimeter of the ammonium chloride solution. Is this action identical in its origin with that produced by the inhalation of am- monia fumes? Inject a larger dose of ammonium chloride to get satisfactory records if the first ones were not good enough (but save the vitality of the animal as much as pos- sible). Empty out the ammonium chloride solution and place adrenaline (1:10,000) in the burette. Allow the animal to recover as fully as possible. Take ACTION OF VANADIUM 465 a normal record (see that all writing pointers are properly adjusted) and inject two cubic centimeters of vanadium solution. Wait for the action of the drug to wear off and then inject one-half cubic centimeter of adrenaline. How do the two sets of records compare? Do you know of any other metal having an action similar to vanadium ? If nec- essary (to get good records) inject another (perhaps larger) dose of vanadium. On what structures does vanadium act ? Can you determine this point from your experiment? (Could you separate the possibility of actions occurring on perfusion wH^ ??in^er-»- Blood. ^og = /0.!i/ to show pulmonary artery, 312 Diuresis, catfeine, 247 Diuretine, 253 Do'g, action of, alcohol on, 136 cannabis indiea on, 205 carbon dioxide on, 131 chloroform on, 77 dose of chloretone for, 233 ether on, 77 ethyl bromide on, 77 heart levers for, 154 spinal, 206 Dog boards, 43 Dog's brain, base of, 175 motor areas of, 106 Dog's heart, 427 Double pole double throw knife switch, 35 Dreser's method for measuring ex- pired air, 187 Drill chuck, Jacob's, 488 Drill, hand, 479, 481 Drill press, 488 Drills, 479, 488 Drum, Harvard long paper, 45 Hiirthle, 45 records, varnish for, 62 stethograph, 41 Drum spinning attachment, 436 Drums, smoking, 61 Duct, Bartholin's, 257, 267, 274 Stenson's, 257 thoracic, collection of lymph from 356, 384 thoracic, dissection for, 144 thoracic, in a cat. 386 Wharton's, 257, 267. 274 Ducts, Ivmphatic, thoracic, 356, 384^ "386 pancreatic, 226, 252. 268, 278 Dudgeon 's sphygmograph, 399 E Ear, rabbits, vessels in shock, 16(5 Edmund's liver oncometer, 417 Electric tuning fork, 145 Electric wiring system, 471 Electrodes, shielded, Harvard, 38 526 GENERAL INDEX Embolism, air, 226 Emery wheel, 487, 495 Emesis, 440 Emodin, 468 Epinine, 124 Equipment and supplies, list of deal- ers in, 515 Equipment of shop, 470 Equipment, list of, for shop, 479 Ergamine, 363 action of, on bronchioles, 373, 378 on lymph flow, 384 " on oxygen consumption, 268 on pulmonary blood-pressure, 369, 372 on respiration, 367 on turtle lung-^ 363 on uterine strip, 380, 381 OIL uterus in situ, 382 Ergot, action of, on capillary circu- lation in frog, 361 on rooster's comb, 360 on uterus of cat, 381 Ergotoxine, 363 action on uterine strip, 380, 381 effect of, on bronchioles, 377, 378 Erigens nerve, 282 Eserine, 342 Esophageal contractions, 136, 137 Ether, action of, on blood-pressure and respiration, 125 on conductivity and irritability on nerve, 57 on dog or cat, 121 on frog, 53 on frog's heart, 65 bottle, milk bottle, 59 bottle, with by-pass, 111, 126 bottle, Woulff, 38 Etherization of dog, method of, 77 of frog, 53 Ethyl bromide, action on dog, 110 on dog or cat, 121 Ethyl chloride, action of, on blood- pressure and respiration, 127 on dog or cat, 121 administration, 121 and bromide, action on conductiv- ity and irritability of nerve, 57 containers, 60 local anesthesia, 64 Experiment, Paul Bert's 120 Expired air, Dreser's method for measuring, 187 Exposures photographic, 502 External jugular vein, 142, 194 Extra drums for records, 101 Eye, dissection of, 394 innervation of, 394 pharmacology and anatomy of, 394 symptoms, certain ones following adrenaline and cocaine, 354 Eyes, excision of, 260 Fatigue of vagus endings, 133 Fatigue tracings, apparatus for re- cording, 245 Fehling's test for glucose, 176 Femoral artery, 107 Fermentation tube, 157 Ferric chloride, 452 Fever, 451 Fibrillation of heart, 287 Files, 479 First thoracic ganglion, 142 Fish tail burner, 485 Fittings, gas pipe, 485, 486, 487 Fixing plates or slides, 504 Fluid, cerebrospinal, action of alco- hol on, 158 recording changes in, 158, 159 Foot bellows, 472 Foot of a dog, sweat secretion in, 271 Forceps, blunt pointed, 49, 50 bone cutting, 320 small sharp pointed, 48 Fork, tuning, electric, 145 Former, for wood, 488 Frames for blue printing, 511 Frog, action of, alcohol on, 133 caffeine on, 241 carbon dioxide on, 113 cocaine on, 350 curara on, 255 morphine on, 172 nicotine on, 300 nitrous oxide on, 113 oxygen on, 113 capillary circulation in, 362, 363 destruction of cerebrum in, 238 exposure of brain, 54 gastrocnemius muscle, 54 injection into anterior lymph sac, 134 method of exposing the heart of, 65 method of pithing, 56 retinal circulation, 171 sciatic nerve, 54 vagus nerve, 65 Frog board, 54 GENERAL INDEX 527 Frog f'li])s, method for making, 495 Frog heart, action of, cocaine on, ;3r)i curara on, 256 nicotine on, 300, 301 method of applying drugs to, 68 Frog heart and nerves, action of lobeline on, 322 Frog heart lever, 66 Frog's blood-vessels, perfusion of, 458, 459 Frog's stomach, ring of, 336 G Gag, mouth, 235 Ganglia, spinal, 349 Ganglion, first thoracic, 142 inferior cervical, 142 Meckel's (spheno-palatine), 265 superior cervical, 265, 274 Ganglionic paralysis by lobeline, 322, 323, 326 Gas reservoir, 186 Gauge drill, 487 pressure, 474 screw thread, 487 wire, 487 Gebauer's ethyl chloride container, 60 Generating oxygen, method for, 185 Gland, thyroid, 142 Glands, lachrymal, innervation of, 265 salivary, innervation of, 257, 266, 274 Glass blowing, 492-495 Glucose, action of yeast and alco- hol on, 157 in urine, 176 Glycogen stores, action of strych- nine on, 224 Glycosuria, from adrenaline, 457 from cyanides, 441 from phloridzin, 457 Green 's method of irrigating the heart, 221 Grouping of students, 33 Guinea x>ig, uterine strip of, 332, 333 Gutherie carbon dioxide generator, 116 H Hack saw, 479, 488 Hale's signal magnet, 36 Hammers, 479, 487 Hand bellows, 107 Hand bracket saw, 485 Hand drill, 479, 481 Hand emery wheel, 487 Hand saw, 479 Handy valve, 474 Hatchet, 479 Harvard, gas chamber, 58 inductorium, 35 membrane manometer, 139 moist chamber, 57 muscle lever, 58 signal magnet, 36 simple key, 35 time clock, 81 Heart, action of, arecoline and at- ropine on, 299 atropine on, 271 barium on, 285, 286 cocaine on, 351, 352 digitoxin on, 408, 418 ether on, in frog, 65 affected by high blood-pressure, 211 and vagus nerves, action of nico- tine on, in frog, 300, 301 action of nicotine on, in turtle, 301 cat's, 426 dog's, 427 effect of respiration of, 110 frog, action of alcohol on, 133 frog, anatomy of, 69 method of irrigating, 221 nerves to, in a dog, 142, 154 revival of, 113 slowing by picrotoxine, 236 turtle, exposure of, 73 turtle's, 74 Heart beat, reflected on lung trac- ings, 216 Heart lever for frog, 66 Heart levers, for dogs, 154 Hearts, action of chloroform on, 70 lymph, frog, 70 Heart tracings, method of recording, in a dog, 152 Heater, electric, 487 Heavy end cutting pliers, 485 Hemostat, 48 Heroine, 346, 348 action after lobeline, 326 action of, on bronchioles and blad- der, 206, 212 Hirudin, to prevent coagulation, 197 Hordenine, action of, on bronchioles, 373, 376, 377 Hydrastinine, action of, on bron- chioles, 242 Hydrastine, action of, on frog, 238 on frog 's heart, 240 on nerves of frog's heart, 240 on nerves of turtle's heart, 241 528 GEIiTERAL INDEX Hydrastine — Cont 'd. convulsions, record of, 239 Hydrochinon, metol, develoiaer, 504 Hydrocyanic acid, general action, 441 Hydrogen peroxide, 441 Hydrophobia, danger of, 78 prophylaxis against, 78 Hyoscine, 342 Hyoscyaniine, 342 Incision for femoral artery, method of, 208 Incision for femoral vein, method of, 208 Independence of bronchial changes, 198 Inductorium, Du Bois-Eej'mond, 36 Harvard, 35 holder, 64 Inferior cervical ganglion, dog, 142 Inferior (recurrent) laryngeal nerve, 142 Inhibition of frog's heart, 133, 134 Injecting burette, 93 method of connecting vein, 93 Injecting pipette, glass, 135 Innervation of, frog's heart, 240 heart, 142, 154 intestine (small), 336, 384 pancreas, 268 retractor penis muscle, 282 salivary glands, 257 vessels in rabbit's ear, 166 Insertion of bladder cannula, 188 Insertion of cannula, carotid, 85, 91 femoral vein, 93, 95 tracheal, 85 Insertion of cannula into pancreatic duct, 278 Insertion of lung shield, 208 Internal jugular vein, 194 Intestinal contractions, action of, adrenaline on, 353 barium on, 353 cocaine on, 353 physostigmine on, 339 apparatus for recording, 279 method for recording, 278 Intestinal loop, action of nicotine on, 307 Intestinal loop oncometer, 223 Intestinal segment, action of adre- naline, lobeline, nicotine, pilocarpine and atropine, 334 method of recording contractions of, 334 Intestine, action of adrenaline, atro- pine, arecoline, barium and pilocarpine on, 278 innervation of, 336, 384 Intestines, action of arsenic on, 460' Intraocular pressure, action of co- caine, barium and adrena- line on, 353 action of nicotine on, 308 method of recording, 308 Intrathoracic pressure, action of arecoline on, 282 method for recording, 282 Intratracheal insufflation, 129 Involuntary nervous system, dia- gram of, 384 Iodide of potassium, 457 Iodine, tincture of, 358 Ipecac, vomiting, 440 Iris, innervation of, 384, 394 Iron rods, etc., supply of, 487 Irrigation of heart, 221 Jack plane, 484 Jacobson's nerve, 256, 274 Jaquet chronograph, 82 Jar, specimen, 46 Jars for anesthetizing cats, 148 Jugular vein, dissection for, 91, 142, 194 external, 85 K Kelene tube, 60 Key, double pole double throvi-, 35 simple, 145 simple Harvard, 35 Kidney, action of, agurine on, 253 ammonium acetate on, 254 ammonium chloride on, 254 arsenic on, 460 caffeine on, 247, 249 diuretine on, 253 Matthews' solution on, 254 sodium chloride on, 254 sodium iodide on, 255 sodium nitrate on, 254 sodium phosphate on, 254 urea on, 254 dissection for, 128 left, exposure of, 164 perfusion of, 342 Kidney oncometer, 41, 162, 163 Eoy's, 42 Kidney volume, action of nicotine on, 307 Kits for plate holders, 505 GENERAL INDEX 529 Kymograph drum, method of smok- ing, 61 Kymograph, long paper, 478-480 Kymograph records, blue prints, 511 prints of, on developing paper, 513 Kymographs, 45 Laboratory supplies and equipment, dealers in, 515 Laboratory table, Avith sink at- tached, 79 Lachrymal gland, innervation of, 2G5 Lacquering, 498 Lamp, blast, 482 spirit, 489 Langendorff method for perfusion of the excised heart, 424, 425 Lantern slides, 51, 500, 502, 505, 506 frame for making mats for, 507 staining of, 508 Laryngeal nerve, superior, 139 Latent period of cardiac sympathetic nerves, 157 Lathe, 477, 488 Left pulmonary artery, dissection for, 110, 166 Left pulmonary vein, dissection for, 110, 166 Leg volume, action of digitoxin and strojjhanthin on, 420 Lenses, 500 Lever, frog heart, 66 Levers, heart, for dog, 154 Levulose, action of, on Ivmph flow, 384 Light, arc, for copying, 501, 502, 506 Light, arc, for laboratory, 472 Lingual nerve, 266, 274 Liquor cresolis compositus, 357 List of apparatus, permanent, 34 List of dealers in supplies and equipment, 515 List of equipment for the shop, 479 Liver, 166 action of adrenaline on, 417 tetramethylammonium chloride on, 423' innervation of, 384 Liver oncometer, brass, 422 Edmund's, 416 Lobcline, action of, after heroine, 327 on bladder, blood-pressure, res- piration and pupil, 325 on frog or turtle heart, 322, 323 on intestinal segment, 334 on turtle lung, 322, 324 on uterine strip, 332, 333 Local anesthesia, etliyl chloride, 64 Locke's solution, 52 Lodal, 337 action of, on blood-pressure and bronchioles, 296 Long paper kymographs, 478, 479, 480 Longitudinal sinus, 105 Lung, left, position of, 166 movements of, 110 turtle, action of codeine on, 215 turtle, action of pilocarpine on, 274 Lung shield, 208, 209 Lung tracings from a turtle, 260-264 Lung volume changes, recording, 196, 206, 210 Lungs, inflation of, 197 innervation of, 384 Lungs of turtle, 260-264 innervation of, 260, 261, 263, 264 Lymph hearts, action of chloroform on, 70 Lymph heart beats, action of curara on, 255 Lymph sac, injections into, 134 Lymphatic system in cat, 386 Lysol, 357 M Machine for artificial respiration, 473-477 Machine, milling, 488 Magnesium, anesthesia, 460 antagonism of calcium, 460 Magnesium sulphate, 466 Mammary artery, 194 Mammary vessels, 109, 166 Manometer, membrane, 139 substitute for, 141 mercury, 37 Mat trimming frame, 507 Material supplied by dealers, 515 Mats for lantern slides, 507 Mechanical procedures, 489 Meckel 's ganglion, 265 Mediastinum, 166 Mediastinum, anterior, 110, 207 Medicine dropper, 68 Medicine, method of giving to dog, 234 Meningitis, 360 Mercury bulb, 206 Mercury vapor lamps, 506 Method, Barbour's for recording uterine contractions, 363, 364 Langendorff, for perfusion of heart, 424, 425 530 GEl^ERAL INDEX Method for, adjusting plethysmo- graph on hind limb, 304 generating oxygen, 185 recording, pulmonary blood-pres- sure, 310-318 oxygen consumj)tion, 180-184 Method of, observing capillary cir- culation, 262, 263 perfusing excised kidney, 342, 343 pithing a dog or cat, 291-294 Metol hydrochinon developer, 504 Metronome, 80 Migraine, action of aspirin on, 451 Milling machine, 488 Moist chamber, Harvard, 57 Monkey wrench, 485 Moreau's experiment, 466, 476 Morphine, action of, on blood-pres- sure and respiration, 177 on bronchioles, 194, 199 on cat, 177 on dog, 175, 204 on frog, 172 on oxygen consumption, 177, 191 on pupils, 175 do not give to animals without special reason, 354 dose of, for dog, 175 excretion of, 175 Motor areas, action of, chloroform on, 103 ether on, 103 ethyl bromide on, 103" exposure of, 103 in dog's brain, 106 stimulation of, 104 Mouth gag, 235 Muscarine, action of, on bronchioles, bladder and blood-pressure, 214, 295 on intestinal contractions, 335 on turtle's lung, 336 Muscle, action of veratrine on, 434 arid nerve, action of, atropine on, 269 action of caffeine on, 243 longus colli, 193 nerve preparation, 243 Muscular work, action of, caffeine on, 245 cocaine on, 352 Muzzle, for dog for anesthesia, 357, 358 Mydriatics, 273 Mylohyoid muscle, 267 Myocardiograph, 149 Myocardiographic tracings, action of, alcohol, 147 brandy, 147 Myocardiographic tracings, action of — Cont'd, whiskey, 147 wine, 147 Myotics, 273 N Nails, 480 Narcotine, action of, on bronchioles, 194, 203 Needle holder, 50 Needles, large, 195 Nerve, cervical sympathetic, 142 chain, sympathetic, 282, 384 conductivity and irritability, 57 depressor, in rabbit, 247 erigens, 282, 384 inferior laryngeal, 142 muscle preparation, 243 optic, 272, 319, 384 phrenic, in a dog, 142, 193 pudic, 282 superior laryngeal, 139, 247 vago-sympathetic, in dog, 142 in frog, 133 vagus, 142, 154, 166, 247 vagus, in frog, 65 Nerve supply to intestine, 336, 384 Nerves, cardiac sympathetic, 142, 147, 154, 155 intraocular, 318, 319, 394 action of nicotine, pilocarpine, and atropine on, 318, 320 of brachial plexus, 142 of frog's heart, 65, 240 thoracic sympathetic, 166 to lachrymal gland, 265, 384 to salivary glands, dog, 257 Nervous system, involuntary, dia- gram of, 384 sympathetic, diagram of 384 Nicotine, action of, on blood-pres- sure, respiration, limb vol- ume and intestinal contrac- tion, 304, 305, 307, 309 on heart and vagus nerves in frog, 300 on heart and vagus nerves in turtle, 301, 337 on intestinal segment, 334 on intraocular pressure, 307, 308 on pulmonary blood-pressure, 310-318 on pupil, 306 on turtle's lungs, 302, 303 on uterine strip, 332, 333 general action on frog, 300 Nitrite, amyl, general action, 404 of sodium, action of, on frog's blood-vessels, 458 sodium, general action, 404 GENERAL INDEX 531 Nitrites, action on bronchioles, 400 Nitroj^en, cffoct on anesthesia, 124 Nitro<>lycerine, action of, on i)ul- nionary blood-pressure, 415 general action, 404 Nitrous oxide, action of, in closed anesthesia, 121 on frog, 113, 117, 118 on guinea pig, 117, 118 on kitten, 117 on pup, 117 on rat, 117 on respiration, 126, 131 apparatus for administering, 130 method for making, 115 some dogs do not take well, 357 tank yoke, 115, 116 Normal salt solution, 52 Note book, permanent, 50 Novocaine, local anesthetic action, 351 spinal anesthesia, 356 Nulling tool, 488 O Oesophageal contractions, 137 {see Esophageal contractions) Oil can, 484 Oncometer, 128, 129, 160 brass, 422 brass, for spleen, 421 Edmund's 416 for intestinal loop, 223 kidney, 41, 162 Eoy's, 42 spleen, 160, 161 Oncometers, method for making, 491 Opening of chest, 102, 108, 109 Operating, table arranged for, 123 Ophthalmoscope, 169-171 Optic lobes, removal of, in frog, 56 Optic nerve, dissection for, 272, 319 Oxygen, action of, on frog, 113 method for generating, 185 Oxygen consumption, action of, j3-tetrahydranaphthylamine on, 453 cyanides on, 441 morphine on, 228 nicotine, plioearpine and atro- jjine on, 318 recording rate of, 180, 181 strychnine on, 226, 229 Oxygen tanks, i^ressure in, 113 yoke for, 115 Pancreas, dissection of, for ducts, 267, 276, 278 Pancreas — Cont M. dissection for, 128 innervation of, 384 Pancreatic ducts, insertion of can- nula in, 276, 278 Pancreatic ducts, 252, 276, 278 Pancreatic secretion, action of at- ropine on, 270, 272 Pantopon, action of, on bronchioles, 194, 200 Paraldehyde, action of, on frog, 168 dose of, for cat or rabbit, 254 Passing catheter, 217 Paul Bert 's experiment, 120 Pelvic (erigens) nerves, 282, 384 Pelvic organs in dog, 216 Penis muscle, retractor, innervation of, 282 Peptone, action on temperature, 451 Perfusion of excised kidney, 342 apparatus for, 343 Perfusion of frog's vessels, 458 Perfusion of heart, Langendorff, 424, 425 Pericardium, 110 opening of, 166 Permanent note book, 50 Peronine, action of, on bronchioles, 194, 201 Pharmacology and dissection of eve, 394 Phases, two, of adrenaline action, 166 Phenacetine, action on fever, 451 Phenol, antidote for, 454, 456 general action of, on dog, 454 general action of, on frog, 454 Phenylsalicylate, absorption and ex- cretion, 452 Phloridzin, glycosuria, 457 Photography, 500 Phrenic nerve, in dog, 193, 207, 268 Phrenic nerves, dissection for, 110, 143 Phrenic nerves, section of, 102 Physostigmine, action of, on blood- pressure, respiration and bladder contractions, 346 on blood-pressure, respiration, intestinal contractions, 339 on frog's heart, 337 on ring of frog's stomach, 337 on the pupil, 350 on turtle's heart, 338 on turtle's lung, 338 Picrotoxine, action of, on blood- pressure, 233 on frog, 231, 232 on respiration, 233 532 GE^^ERAL IISTDEX Pigeon, brain of, 173, 174 semicircular canals of, 174 Pilocarpine, action of, on adrenal glands, 278 on bladder, 278 on bronchioles, 287, 295 on frog's heart and vagus nerves, 273 on frog 's retinal circulation, 274 on intestinal contraction, blood- pressure and respiration, 283 on intestinal segment, 334 on pancreatic secretion, 275 on pupil, 275 on rate of oxvgen consumption, 283 on salivary secretion, 275 on turtle lung, 274 on uterine strip, 332, 333 Pipe cutter, 487 Pipe, gas, fittings, 485-487 Pipe stock and dies, 485 Pithing a dog or cat, method for, 291-294 Pithing a frog, method of, 56 Pituitrin, action of, on bronchioles and blood-pressure, 391 on capillary circulation, 387 on frog or turtle heart, 388 on intestinal contractions, 392 on lymph flow, 384 on pulmonary blood-pressure, 384 on turtle lung, 388 on urine secretion, 392 on uterine strip, 390 on uterus in situ, 382, 389 Planes, 484 Plethysmograph, 398 action of amylnitrite with, 397 Plethysmograph for dog's hind limb, 304 Pleura, parietal, 208, 209 Plexus, Auerbach's, 336 Meissner's, 336 pelvic, 384 vesical, 384 Pliers, 479, 485 Points, writing, adjustment of, 98 Potassium chloride, action of, on heart, 424 Potassium iodide, absorption, excre- tion, 457 Preparation, (gastrocnemius) muscle and nerve, 243 Pressure, air, negative, 474, 475 positive, 474, 475 Pressure — Cont 'd. intraocular, method of recording, 308 of air for intratracheal insuf- flation, 132 pulmonary, action of nicotine, ad- renaline, barium on, 310-318 method of recording, 310-314 Pressure bottle, on pulley, 97 Print, paper, blue, 510, 511 Printing blue prints in sunlight, 511 Printing frames for blue prints, 511 Printing paper, 508 Prints, blue, 51, 510 bromide solution for, 509 developer for, 508, 509 developing, 509 drying and mounting, 510 fixer for, 509 fixing, 510 Print trimmer, 63 Probe, dissecting, 49 Prussic acid (hydrocyanic), 441 Pudic nerve, 282 Pulmonary artery, dissection for, 306, 312, 313, 314 special cannulas for, 315 Pulmonary blood-pressure, 415 action of ergamine on, 369, 372 Punch for metal, 485 Puncturing spinal canal, 349, 356, 359 Pupil, action of, adrenaline on, 272 atropine on, 269 cocaine on, 350 nicotine on, 306 physostigmine on, 350 pilocarpine on, 275 sympathetic on, 100 Pupils, action of morphine on, 190 Pyro developer, 503 Q Quinine, action of, on fever, 451 on frog or turtle heart, 447 on white corpuscle, Binz's ex- periment, 447 E Eabbit, action of, agurine on, 253 diuretine on, 253 caffeine, diuresis in, 247 cervical nerves in, 247 depressor nerves in, 247 doses of urethane for, 247 etherization of, 247 uterine strip, 332, 333 CxENERAL INDEX Hat, uetion of, curbou dioxiilc on, 117 ethyl cliloridc on, 117 increased atiiios])heric pressure on, 117 nitrous oxide on, 117 Rate of oxygen consumption, appa- ratus for, 180, 181 Reaction time, action of, caffeine on, 244 strychnine on, 230 whiskey on, 144 Recorder for- drops of urine flow, 249 Recording, bladder contractions, mercury bulb for, 188, 206 bladder contractions, apparatus for, 207 contractions of intestinal segment, 334 convulsions in a frog, 218 turtle lung tracings, 260-264 uterine strip contractions, appara- tus for, 333 Records, apparatus arranged for several on drum, 165 Rectum, innervation of, 384 Reducing bath for slides or nega- tives, 505 Reducing bodies, Fehling's test for, 176 Reservoir for gas, 186 Respiration, action of, carbon diox- ide on, 117 nitrous oxide on, 126 Cheyne-Stokes, 176, 355 recording, 97, 98 recording, Cushny 's method, 99 Resuscitation of dog, 102, 140 Retinal circulation, action of, chlo- ral on, 169 pilocarpine, arecoline and atro- pine on, 274 seen with ophthalmoscope, 170, 171 Retinal corpuscles, action of amyl- nitrite on, 400 Retinal vessels, action of amylni- trite on, 401 Retractor penis muscle, innervation of, 282 Rhubarb, 466 Ring of frog's stomach, 336 Ringer's solution, 52 Risus sardonicus, 224 Rods, brass, 480, 482 Room for the shop, 470 Rooster's comb, action of ergot on, 360 Rouge, 498 li'uhlxT dam, attaching to stetlio- graph, 484 attaching screw or tack to, meth- od of, 484 S Salivary ducts and nerves, 257, 266 Salivary glands, action of nicotine, pilocarpine, and atropine on, 318 dissection to show, 274 general plan of innervation, 274 Salol, 452 Salt solution, 52 Saphenous nerve, 93 Saw, hack, 479, 488 hand, 479 hand bandage, 108 Scalpel, 49 Sciatic nerve carries sweat nerves to foot, 271 Sciatic nerve stimulation, effect on blood-pressure, 249 effect on respiration, 249, 258 Sciatic nerves, dissection for, 237 stimulation of, 237 Scissors, dissecting, 49 Scopolamine, action of, on frog, 273 Scratch awl, 485 Screw, wood or metal (machine), 485 Screw drivers, 479 Secretion of pancreas, how con- trolled, 268 action of atropine on, 270 Secretion of salivary glands, action of atropine on, 270 Section of the phrenic nerves, 179 Sensation not prevented by curara, 258 Serrefine, 48 Shaper (planer), 488 Shield, lung, 208, 209 Shielded electrodes, 38 Shock, action, vaso-constrictor cen- ter in, 166 Shock, rabbit 's ears in, 166 Shop work, 470 Signal magnet. Hale 's, 35 Harvard, 35 manometer, 37 Simple key, 145 Simplex heater, 487 Sinus, longitudinal, 105 Skull of cat, mesial section of, 179 u])per surface of, 178 Small electric heater, 487 Small vise, 479 Smoking drums, 61 534 GENEKAL INDEX Snips, tinners, 104, 479 Sodium citrate solution, 53 cyanide, general action, 404, 441- 445 hydroxide, 462 nitrite, action of, on frog's blood- vessels, 458 action of on perfused kidney, 342 action of on ring of frog's stom- ach, 337 orthovanadate, action of, on per- fused kidney, 345 sulphate, 454 diuresis, 249, 251 sulphide, 441 Sodium-theobromine-acetate, 253 Sodium- theobromine-salicylate, 253 Soldering, 483, 489-492 acid, 483, 489 aluminum, 489 tracheal cannula, 490 Solution, Locke 's, 52 NaOH for closed anesthesia, 122 normal salt, 52 Ringer's, 52 sodium citrate, 53 Tyrode's, 52 Solutions, injection of, 94 Somnoform, 121 Special apparatus, 52 for obtaining bronchiole tracings, 288, 289 Speed lathe, 488 Sphygmograph, action of amylni- trite on, 400 Dudgeon's, 399 Spinal anesthesia, 356 Spinal canal, puncture of, 349, 359 Spinal dog, method of preparing, 194, 291-294 Spinal ganglion, 349 Spinning attachment for drum, 436 Splanchnic nerves, dissection for, 166, 167 functions of, 167 Spleen, dissection for, 128 innervation of, 384 oncometer, 160, 161, 421 method of applying, 161 volume, action of nicotine on, 307, 309 Squares, try and carpenter 's, 485 Staining lantern slides, 508 Stand, copying, 501 Stands, castings for, 496 making, 496, 497 Starch granules, injected into ca- rotid artery, 197 Stellate ganglion, 154 Sterilization of hands, 358 Stethograph drum, 41 Stillson wrenches, 487 Stimulation of motor areas, 104 Stocks and dies, 485 Stomach, innervation of, 384 Stomach tube, passing in a dog, 234 Straight cannula, glass, 107 Strophanthin, action of, on perfused heart, 424, 425 on pulmonary blood-pressure, 415 general action, 420 Strychnine, action of, on blood-pres- sure, 222 on frog, 217 on frog's cardio-inhibitory nerves, 220 on frog's heart, 220 on oxygen consumption, 226 on reaction time, 230 on respiration, 222 on special senses, 231 on turtle's heart, 220 on vagus nerve in turtle 's heart, 220, 222 and eurara, action of, on blood- pressure and respiration, 257 gastrocnemius contraction records, 218, 219 Subclavian ansa, 154 Subclavian artery, dissection for, 143 Subclavian vein, 142, 194 dissection for, 143 Substitute for membrane manometer, 141 Superior cervical ganglion, 154, 245, 265, 274, 394 Superior laryngeal nerve, 139 Superior mesenteric ganglion, 384 Supplies and equipment, dealers, 515 Supplies of brass, 480 Supplies of iron rod, etc., 487 Sweat secretion, action of atropine on, 270 Sympathetic, cervical nerves and ganglion, 142 ganglion, inferior cervical, 154 nerve, cervical, in rabbit, 246 nerves, cardiac, in cat, 155 cardiac, in frog, 66 cardiac, in turtle, 75 in neck of rabbit, 247, 248 to frog's heart, 240 to heart, 154 nervous system, diagram of, 384 thoracic trunks, 166 System, electric wiring, 471 GENERAL INDEX 535 T Table, arranged for operating, 123 laboratory, 79 Tables, small supporting, 47 Tambour, adjustable, 40, 483 cheap form, 484 Marey, 40 Tanks, carbon dioxide, 116 nitrous oxide, 113 oxygen, 113 Tape worms, 230 Tartar emetic, 462 Taste organs, 351 Technic for inserting bladder can- nula, 188 Telephone, for reaction time, 145, 146 Temperature, rectal, 148 Tetramethylammonium chloride, ac- tion of, before and after at- ropine, 329 on blood-pressure, respiration, bladder and pupil, 325, 330, 331 on bronchioles, 331 Thebaine, action of, on bronchioles, 194, 377 on frog, 173 Thoracic duct, 356, 384, 386 Thoracic sympathetic, 166 Thyroid gland, 142 Time clock. Harvard, 81 Time recording metronome, 80 Time recording watch, Lieb-Beckcr, 80 Tincture of iodine, 358 Tinner's snips, 479 Trachea, dissection to expose, 86 Tracheal cannula, attachment of other bottle to, 89 brass, 39 insertion of, in dog, 89 soldering, 490 Tracing trimmer, 63 Tracings from turtle's lungs, 260, 264 Transverse scapular artery, 194 Trephine, 105 Trimethylamine, action of, on blood- pressure, respiration and in- testinal contractions, 339, 340, 341 Tripoli, 498 Trocar and cannula, 359 Try square, 485 Tube, stomach, passing in a dog, 234 into larynx, 235 to pass through chest, 196 Tubing, brass, .480 Turning attachments, 488 Turning lathe, 477, 488 motor driven, 488 Turtle board, operating, 46 Turtle lung tracings, method for making, 260-264 Turtle's heart, 74 action of, alcohol on, 135 chloroform on, 76 ether on, 71 hydrastine on, 241 and vagus nerves, action of atro- pine on, 269 exposure of, circular saw for, 73 method for recording heart trac- ings, 72, 73 sympathetic nerves to, 77 Turtles, list of dealers supplying, 515 Turtle 's lungs, action of, lobeline on, 323, 324 nicotine on, 302, 303 physostigmine on, 338 dissection to show, 261 Turtle's vagus nerve, 71, 73, 75 Tyramine, 371 action of, on blood-pressure, 370 on capillaries, 363 Tyrode 's solution, 52 U Ureter, innervation of, 384 Ureteral cannula, glass, 225 Ureters, dissection for, 226 Urethane, action of, on frog, 168 dose for cat, 254 dose for rabbit, 247, 254 Urine, action of curara on secretion of, 257 collecting from bladder cannula, 188 testing for glucose, 189, 248 Urine flow, action of, caffeine on, 247, 249 chloral on, 252 Matthews' solution on, 254 sodium iodide on, 255 sodium sulphate on, 251 urea on, 254 drop recorder for, 249, 250 normal rate of, 250 Uterine contractions, Barbour's method of recording, 363, 364 method of recording, 333 method of recording in situ, 382 Uterine strip, action of, lobeline, nicotine, and pilocarpine on, 332, 333 536 GENERAL INDEX Uterine strip, action of — Cont 'd. pituitrin on, 390 method of recording contractions of, 333, 380, 381' Uterus, action of, barium on, 284 erganiine and ergotoxine on, 363, 366 ergot on, 381 dissection for, 230 innervation of, 38-1 V Vacuum, pump, 473, 474 Vagi, action of, on turtle's lung, 260-264 section of, effect on respiration, 236 Vago-sympathetic nerve in frog, 65, 66, 133 Vagus and sympathetic nerves in the turtle, 75 Vagus and sympathetic nerves to the heart, 154 Vagus nerve, dissection for, in dog, 85, 90, 142, 194 in frog, 65 in turtle, heart, 71, 135 method of stimulating in turtle, 72, 75 Vagus nerves, action of atropine on, 269, 273 Valves for artificial respiration ma- chiues, 473-477 Vanadium, action of, on pulmonary blood-pressure, 394 general action, 462-465 Varnish for tracings, 62 Varnishing pan for varnishing long tracings, 63 Varnishing rack and pan, 62 Vein, external jugular, 91 femoral, dissection for, 94 left pulmonary, 112 saphenous, 93 insertion of cannula in, 93 subclavian, 142, 143, 155, 194 Veins, jugular, 142, 192, 194 ligation of, 193 Veratrine, action of, on blood-pres- sure, respiration and intes- tinal contractions, 437 Veratrine, action of — Cont 'd. on frog's skeletal muscle, 434 on turtle's lung, 437, 438 frog, general action, 433 frog or turtle heart, action on, 434, 435 heart tracings and blood-pressure, 440 Vertebral artery, 193, 195 Vessels, blood, of a frog, perfusion of, 458, 459 Vieussenii, annulus of, 143 Visceral organs, dissection of, dog, 167 Vise, large, 487 small, 479 Vision, action of amylnitrite on, 403 Vitality of spinal dog, 205 Vomiting, apomorj)hine, 440 ipecac in, 440 tartar emetic in, 462 W Wharton's duct, 257, 259, 266, 274 dissections for, 266, 274 Wheel, emery, 487, 495 Whiskey, action of, on blood-pres- sure and respiration, 136 Wine, action of, on blood-pressure and respiration, 136 Wire, copper, 484 Wire gauge, 487 Wiring system for electric current for laboratory, 471 Wood former, 488 Wood lathe, 488 Work bench, 485 Worms, tape, 230 Woulff, ether bottle, three necked, 38 Wrenches, 485 Stillson, 487 Writing points, adjustment of, 98 Y Yeast, fermentation by, 157 Yokes for gas tanks, 115, 116 Zinc sulphate solution, for boot elec- trodes, 59 Date Due ^(kl^ ^ ifirw iBw ^>