338 EXPERIMENTAL PHARMACOLOGY 



strong tonic contraction! If it is, can it contract any 

 further? Adjust the weight and pour into the beaker one 

 or two cubic centimeters of eserine solution. (Add more 

 drug if necessary.) What conclusions can you draw? Add 

 some atropine to the beaker and note the results. 



The experiment may be repeated (a fresh stomach ring 

 may be needed) and after the eserine action has been well 

 developed sodium nitrite solution (one-half per cent a 

 few cubic centimeters) can be added to the beaker. What 

 do you observe? What conclusions can you draw? On 

 what structures and in what manner does each drug act? 

 Of what clinical significance is each of these actions? 



EXPERIMENT LXXXVII. 

 Physostigmine. (Turtle: Heart Tracing.) 



1. Repeat Experiment LXXX.V using a turtle instead of 

 a frog. Does the drug act in any way on the crescent 

 ganglia or the post ganglionic fibers? Compare this with 

 nicotine and arecoline. 



EXPERIMENT LXXXVIII. 



Physostigmine, (Adrenaline, Atropine). (Turtle: 



Lung Tracing.) 



1. Arrange a turtle for recording lung tracings and then 

 inject into the heart one or two cubic centimeters of eserine 

 solution (one cubic centimeter equals one-half milligram). 

 What action has the drug in this case? Is this a ganglionic 

 or nerve ending reaction? Could you prove your conclu- 

 sion? Now make a second injection of eserine into the 

 heart (if it has not already become too weak or stopped) 

 and follow this with an injection of adrenaline (1:1000). 

 Atropine may be used instead of adrenaline (or better a 

 second experiment on a fresh animal may be performed). 



