320 



EXPERIMENTAL 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-fourths of a 

 cubic centimeter. This will vary with the size of the ani- 

 mal and also with 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 with 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 will tolerate it well inject another 



