Studies of Postcastrational Adrenal Cortical Changes

The gonadotropins produced by the adenohy pophysis control the section of ovarian steroids which feed back to regulate the secretion of the adenohypophysis. In some animals this homeo static ability is so highly developed that the re moval of the ovaries results not only in increased gonadotropin secretion but in the eventual conver sion of the adrenal cortex into a secretor of sex steroids which are ordinarily associated with the gonad. Histologic changes in the adrenal which we associate with sex hormone secretion in the mouse (6) have been reported following gonadectomy in the dog (7), guinea pig (28), hamster (18, 25), rat (14, 15), and goat (2@). The induction of these morphologic changes and subsequent sex hormone secretion followingonadectomysuggeststhatthe increase in gonadotropin following castration might be responsible forthe adrenalreorganiza tion.This hypothesishas been supportedby the demonstrationthat injections of both androgen (18,24)and estrogen(24)willpreventpostcastra tional nodular hyperplasia. Hypophysectomy will also prevent nodular hyperplasia (8). Since the pituitary produces a variety of hormones, it is nec essaryalsotoruleout theroleof ACTH and a di rect effect of lack of estrogen or androgen upon the