336 EXPERIMENTAL PHARMACOLOGY 



testine.) Again add pilocarpine to the beaker and if a 

 contraction is produced then add atropine solution (one 

 cubic centimeter equals five milligrams). Do you obtain 

 satisfactory results ? State in full your conclusions. Add 

 some barium chloride (one-half per cent solution) to the 

 beaker and note the results. 



A part or all of the experiment may be repeated by us- 

 ing a longitudinal strip of the small intestine. What effect 

 does adrenaline have on longitudinal strips? What is the 

 innervation of the small intestine ? (Fig. 318). 



The experiment may be repeated using a ring of the 

 stomach of a frog. 



EXPERIMENT LXXXIV. 

 Muscarine, Atropine. (Turtle: Lung- Tracings.) 



1. Prepare a turtle for taking lung tracings. Inject into 

 the heart one or two cubic centimeters of muscarine solu- 

 tion (one cubic centimeter equals one-halt' milligram) and 

 record the result. Do you get a contraction of the lungs? 

 How do you explain your results? Is the heart beating 

 well? Inject one or two cubic centimeters of atropine solu- 

 tion (one cubic centimeter equals one-half milligram). Do 

 you get a contraction or a relaxation of the lungs ? How do 

 you explain the results ? Perhaps you may want to repeat 

 the injection of atropine on a second turtle. How do your 

 results compare with those obtained in a dog or cat ? 



If the lungs relax after a contraction can the relaxation 

 be recorded if the weight of the liver and intestines is rest- 

 ing on the pulmonary sacs? Could you modify the experi- 

 ment to advantage in any way? It is usually advisable to 

 dissect out the liver and intestines and most of the skeletal 

 muscles before trying to record lung contractions. Do not 

 injure the vessels going to the lungs. 



