Stimulation of Adrenal Secretion. 79 
After an initial shortening the strip contracted rhythmically 
in blood from a quiet 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 effect 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 
following reasons. (1) The effect was obtained in blood from the 
vena cava near the liver when that from the femoral vein taken 
simultaneously produced no inhibition. (2) Removal of the 
adrenal glands after tying the adrenal vessels resulted in a 
failure of excitement to produce the effect. (3) Adding varying 
amounts of adrenalin to inactive blood evoked all the degrees of 
relaxation that have been observed in excited blood. (4) Excited 
blood which produced prompt inhibition lost that power on stand- 
ing or on being agitated by bubbling oxygen. These conditions 
together with the evidence that sympathetic impulses increase 
the secretion of the adrenal glands, and that during such emotional 
excitement as was here employed signs of sympathetic discharge 
were observable in the animal from the eye to the tip of the tail, 
prove that the effect was due to adrenal secretion. 
Injected adrenalin is capable of inducing an atheromatous 
condition of the arterial wall in rabbits, especially in elderly in- 
dividuals, and is also capable of evoking hyperglycemia with 
glycosuria. As Ascher has shown, by prolonged stimulation of the 
splanchnic nerves, prolonged secretion of the adrenal glands with 
maintained high blood pressure can be produced. In the light of 
the results here reported the temptation is strong to suggest that 
some phases of these pathological states are associated with the 
strenuous and exciting character of modern life acting through the 
adrenal glands. This suggestion, however, must be put to experi- 
mental test. 
