Adrenal Cortical Hormone and Tissue Respiration.

Abstract

Aub, Forman, and Bright reported a 25% decrease in basal metabolism in totally adrenalectomized cats. Injections of extracts at that time available were without effect in increasing this diminished metabolism. Variable results have been reported by others.3-6 Swingle, Pfiffner, and Webster have shown that the basal metabolism of bilaterally adrenalectomized cats falls progressively from the 6th day postoperative to a level approximately 50% below normal when the animal becomes prostrated. Administrations of adrenal cortical extract to prostrate animals raises the metabolism within 24 to 48 hours, this may reach a point from 10 to 18% above normal in 48 to 72 hours. Upon discontinuing the injections the metabolism returned to normal. These same changes occurred in animals previously thyroidectomized. Subcutaneous injections of large amounts of cortical hormone were without effect in increasing the respiratory metabolism of normal cats or rabbits, but similar injections in thyroidectomized animals increased metabolism 15 to 30% in 80% of the animals. They suggest that the cortical hormone possibly acts directly on the oxidation-reduction processes which occur within the tissues themselves, an action which is more rapid than that of thyroxin. Engle, Britton, and Kine were able to demonstrate that injections of adrenal cortical hormone increased the endurance capacity and energy output of treadmill-exercised dogs by about 100%. This effect persisted for 10 to 15 days. The present investigation was begun to determine whether the cortical hormone has any effect on the QO2 of surviving muscle fasciculi.