Secretion of Pregn-4-ene-3,20-dione (Progesterone) in vivo by the Adrenal Gland of the Rat

Abstract

Feder, Resko and Goy¹ suggested recently that the adrenal gland of the rat secretes progesterone. They observed that the arterial blood of female rats still contained significant amounts of progesterone 25 days after bilateral ovariectomy; 8 h after additional adrenalectomy, however, the steroid was no longer detectable. Because the rat is often used for experiments in reproductive physiology, it is important to assess the contribution of the adrenal gland to the total available progesterone in the female rat. We have therefore measured the secretion of progesterone from the adrenal gland by estimating the amount of the steroid secreted into the adrenal venous blood. Experimental conditions were maintained comparable with those used recently for measuring the secretion of progesterone by the ovary of the rat^2–4.