328 EXPERIMENTAL 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). "When 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 you find these structures in a dis- 

 section of the animal I 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? How do you explain this? Could you 

 prove the truth or falsity of your conclusions ? How would 

 you do this? AYhen 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. 



Injec-t 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. Watch the 

 pupils closely as the adrenaline is injected. Xow stimulate 

 each vagus nerve and see how the heart, blood-pressure 



