[The endometrium of intact or castrated rats. Effects of hormonal stimulation. A scanning electron microscopy study]

The endometrium of female rats during the estrous cycle and of female ovariectomised rats under hormone stimulation, has been studied by scanning electron microscopy. The endometrium underwent marked cyclical changes; the development of microvilli was noted before ovulation, and secretory phenomena started during proestrus but remained discrete throughout the cycle. The rat endometrium was also characterised by the fact that ciliated cells were scarce. Following ovariectomy, the endometrial surface pattern was similar to that of the menopausal woman endometrium. After estrogen or estroprogestogen stimulation, by the methods usually employed in endocrine pharmacology, the general endometrial pattern was very different to that observed during the reproductive cycle in rats.