310 EXPERIMENTAL PHARMACOLOGY 



drug to act. When the effects are well marked inject one- 

 half cubic centimeter of adrenaline. What conclusions can 

 you draw from your records! 



Inject one-fourth cubic centimeter more of adrenaline (if 

 necessary) to get the animal into as good condition as pos- 

 sible. Then empty out the adrenaline (save it) and fill the 

 burette with atropine solution (one cubic centimeter equals 

 one milligram). 



Inject another dose (estimate the size to get the results) 

 of pilocarpine and Avhen the reaction comes on inject one 

 cubic centimeter of atropine. Do you get what you should 

 get? What conclusions can you draw? Stimulate the va- 

 gus nerve and see if your eye record is affected. What is 

 the relation between the cervical vagus nerve trunk and the 

 eye in the dog? How does this compare with a man? If 

 you get any eye records study and explain carefully the 

 exact cause of these records. Are they due to local or 

 remote actions of the drugs concerned? 



Empty out the pilocarpine and put barium chloride solu- 

 tion in the burette. Inject five cubic centimeters (one-half 

 per cent) of the solution. Obtain as good records as you 

 can. Then inject sufficient barium to kill the animal. Dis- 

 cuss the action of the drugs used in this experiment. Com- 

 pare your results with those obtained by other members 

 of the class. 



EXPERIMENT LXXVII. 



Nicotine, Adrenaline, Barium. (Dog: Pulmonary Blood- 

 pressure, Carotid Pressure.) 



1. Etherize a dog (twelve or fourteen kilos preferred). 

 A small dose of chloretone may be given to some advan- 

 tage. Arrange for a perfectly reliable artificial respira- 

 tion (a power driven machine is greatly to be preferred). 

 Isolate and ligate loosely both vagi. Arrange to record 

 carotid blood-pressure. The injecting burettes contain nic- 



