7 Immunocytochemical localization of oestradiol and progesterone receptors in human endometrium: A tool to assess endometrial maturation

Abstract

Uterine oestrogen (ER) and progesterone (PR) receptors are subject to fine hormonal control by oestradiol and progesterone. In order to assess the role of ER and PR measurement in the evaluation of endometrial maturation, both receptors were studied by immunocytochemical techniques using monoclonal antibodies during the menstrual cycle, and in women with inactive ovaries treated by different regimens of hormonal substitution with oestradiol and progesterone. During the normal menstrual cycle, the concentrations and distribution of ER and PR changed markedly. During the mid follicular period (days 7-8), a small proportion of stromal and glandular cells stained positively for PR while staining for ER was more intense and more frequent. During the late follicular phase and early luteal period (days 9-19), the staining for PR increased markedly in glandular cells. During the mid and late luteal phase (days 21-27), ER and PR staining disappeared in glandular cells. Thus, while oestradiol increases the staining for ER and PR in both glands and stroma, progesterone decreases ER and PR staining in the glands in a dramatic fashion. These variations, especially the disappearance of PR under the effect of progesterone, are potentially useful for studying the cumulative effect of progesterone on endometrial maturation. This was confirmed in anovulatory women, where a late luteal phase aspect was observed, i.e. the absence of a reduction in ER and PR in glandular cells. In women with ovarian failure, the disappearance of ER and PR in glandular cells is correlated with the duration of progesterone therapy. In addition, we observed a staining for PR in muscular cells of human uterine arteries suggesting a role for steroid hormones in uterine vascular changes during the menstrual cycle. Preliminary observations in women with ovarian failure suggest that oestradiol may not be necessary during the luteal phase to induce normal secretory transformations of the endometrium. © 1991 Baillière Tindall. All rights reserved.