EFFECTS OF PROGESTERONE AND OESTRADIOL-17β ON THE LUMINAL EPITHELIUM OF THE MOUSE UTERUS

Abstract

Summary. Daily injections of progesterone produce changes in the morphology of the uterine epithelium similar to those seen during early pregnancy. These changes are associated with closure of the uterine lumen and with the suppression of epithelial cell division. Identical effects are produced by synthetic progestins but not by oestradiol, testosterone, cortisol, desoxycorticosterone or combinations of these hormones. Large doses of oestradiol inhibit the effects of progesterone and produce some epithelial mitosis. It seems that luminal closure and epithelial cell division are the products of two mutually exclusive pathways of epithelial development. In some experiments, physiological doses of oestradiol augmented the effects of progesterone. It is emphasized, however, that progesterone alone is wholly effective in producing all the changes described, including luminal closure.