RECIPROCAL RELATION BETWEEN THE HYPOPHYSIS AND ADRENALS IN FETAL RATS: EFFECTS OF UNILATERAL ADRENALECTOMY AND OF IMPLANTED CORTISONE, DOCA AND SEX HORMONES¹²³

Abstract

WE HAVE recently presented some observations which suggested that in the fetal rat the hypophysis cerebri secretes a hormone (ACTH), that this hormone stimulates the secretion of an active principle(s) by the adrenal cortex and that the cortex does not produce any appreciable quantity of androgen, if any (Kitchell and Wells, 1951). It was observed that in fetuses of the 20th day the adrenal cortex has two zones. In those of the 22nd day it has three: outer, intermediate and inner. The cells of the intermediate zone are large, and they contain droplets of osmiphilic lipids. Implanted ACTH speeds up the growth of the cortex, while the removal of the fetal hypophysis by decapitation retards it. This retardation can be prevented by means of injected ACTH. Adrenalectomy does not inhibit the growth of the reproductive organs in the male. The view that ACTH from the fetal hypophysis stimulates the secretion of an active principle by the developing cortex