Granulosa Cell Maturation in the Rat: Increased Binding of Human Chorionic Gonadotropin Following Treatment with Follicle-Stimulating Hormone<i>in Vivo</i>¹¹

TLDR

The study examined the role of follicle‑stimulating hormone in ovarian development of immature rats. FSH treatment induced hCG binding and 3β‑hydroxysteroid dehydrogenase activity in granulosa cells, indicating that FSH activates hCG receptors and steroidogenic enzymes in these cells. Endocrinology 95: 818 (1974).

Abstract

The role of follicle-stimulating hormone (FSH) in ovarian development was studied in immature rats. Autoradiographic analysis of gonadotropin binding sites revealed that FSH bound to granulosa cells while human chorionic gonadotropin (hCG) bound to thecal and interstitial cells in 25-day-old rats. Following 2 days of treatment with rat FSH (rFSH), hCG binding was observed in the granulosa cells of stimulated follicles. Histochemical localization of 3β-hydroxysteroid dehydrogenase activity also was apparent in granulosa cells from animals treated with FSH. Granulosa cells from rats treated with either hCG or diethylstilbestrol for 2 days failed to show consistent hCG binding. Isolated granulosa cells from intact and hypophysectomized rats treated with FSH demonstrated a greater binding capacity for hCG than granulosa cells removed from saline-treated animals. These results suggest that FSH administered in vivo may act on granulosa cells to induce or activate receptors for I_H (hCG) and 3β-hydroxysteroid dehydrogenase activity. (Endocrinology95: 818, 1974)