Adrenal medullary secretion in response to hemorrhage in the dog.

Abstract

In dogs anesthetized with sodium pentobarbital, adrenal venous blood was collected and analyzed for adrenaline and noradrenaline by the fluorimetric method. Four groups of experiments were performed: (1) Bleeding in intact dogs. (2) Infusion of dextran or Ringer's solution after bleeding in intact dogs. (3) Bleeding after section of the splanchnic nerves. (4) Bleeding after section of the buffer nerves for blood pressure. A definite increase in adrenal medullary secretion was observed in intact dogs when over one-fourth of the total blood volume was bled. Infusion of dextran or Ringer's solution after bleeding was found to inhibit the adrenal medullary response to hemorrhage. After section of the splanch is nerves the secretion of adrenaline and noradrenaline of the adrenal gland on that side was not increased by bleeding. After section of the buffer nerves for blood pressure the adrenal medullary secretion was increased after bleeding, though there was a delay in reaching high level of adrenal medullary secretion.