782 



THE ENDOCRINE ORGANS, OR DUCTLESS GLANDS 



curred ; that is, if the solution produces inhibition of the intestine along 

 with augmentation of the uterus, it must contain epiiiephrine. 



3'. The fresh carotid artery of the sheep. A ring cut from the artery 

 is suspended in oxygenated Locke's solution and attached below to a 

 small hook and above to a loaded muscle lever, by which the contraction 



Fig. 193. Tracing showing the effect of epinephrine on the intestinal contractions and on the 

 arterial blood pressure. (The preliminary addition of barium to the nutritive fluid may be disre- 

 garded.) (From Jackson.) 



of the muscle fibers can be magnified. Epinephrine causes the muscle to 

 contract, but the test is not so sensitive as the foregoing, especially in 

 the presence of blood serum, because the pressor substances therein con- 

 tained also cause contraction. Blood plasma does not contain the pres- 

 sor substances, so that oxalated plasma should be used in place of serum 



