ACTION OF CURARA 259 



the reaction of the pupil when the vago-synipathetic trunk 

 is stimulated 1 ? 



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 with the natural nervous im- 

 pulse? 



Now 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 with more 

 injections as fast as the animal can well tolerate the drug. 

 Watch for convulsions. Do you get these? What muscles 

 are affected by curara ? What ones are not affected ? Does 

 the action of strychnine extend to any of those not affected 

 by curara? If so what 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 with the action of strychnine in a noncurarized 

 animal? Explain this. Stimulate the vagus and sciatic 

 nerves 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 with 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 submaxillary and sublingual ducts. Also dissect out the 

 chorda tympani 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 240. 

 Stimulate the chorda tympani nerve and see if you can ob- 

 serve any effects on the rate of salivary secretion. What 

 action has curara on the salivary apparatus? Have you 

 demonstrated this? Kill the animal with a large dose of 



