THE STIMULATION OF ADRENAL SECRETION BY 

 EMOTIONAL EXCITEMENT. 



By W. B. cannon, M.D. 

 From the Laboratory of Physiology in the Harvard Medical School. 



(Read April 2^2. rgii.) 



Dreyer's demonstration that splanchnic stimulation increases the 

 content of adrenal secretion in blood from the adrenal veins has been 

 confirmed by several observers. Adrenal secretion therefore is under 

 control of the sympathetic system. 



Major emotional disturbances indicate the dominance of sympa- 

 thetic impulses. In the cat, for example, fright causes dilatation of 

 the pupils, inhibition of the stomach and intestines, rapid heart, and 

 erection of the hairs of the back and tail. Do not the adrenal glands 

 share in this widespread subjugation of the viscera to sympathetic 

 control ? 



To try this suggestion the inhibition of contraction in strips of 

 longitudinal intestinal muscle, sensitive to suprarenin i to 20,000,000, 

 was used as a biologic test. From the cat when quiet, and again 

 from the animal when excited by a barking dog, blood was obtained 

 by introducing, through the femoral vein, into the inferior vena cava 

 to the region of the liver, a small vaselined catheter. The blood thus 

 obtained was defibrinated and applied to the intestinal strip at body 

 temperature. 



After an initial shortening the strip contracted rhythmically in 

 blood from a cjuiet animal. In no instance did such blood produce 

 inhibition. On the other hand, blood taken from animals after the 

 emotional disturbance, showed more or less promptly the typical 

 relaxing effect. As the emotional period was prolonged, the eft'ect 

 became prompter and more profound. 



The view that inhibition of the contracting intestinal strip is due 

 to an increased content of adrenal secretion is justified for the fol- 



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