THE EFFECT OF HEMORRHAGE UPON ALDOSTERONE SECRETION IN NORMAL AND HYPOPHYSECTOMIZED DOGS*

Abstract

Hemorrhage stimulated adrenocortical secretions by two mechanisms. In the normal dog, acute hemorrhage caused release of ACTH which stimulated both glucocorticoid and aldosterone secretion. However, if glucocorticoid secretion was maximal prior to hemorrhage, only aldosterone secretion was stimulated, even if exogenous ACTH was administered. Hemorrhage experiments in the hypophysectomized dog demonstrated that a mechanism independent of the pituitary stimulated primarily aldosterone secretion.