تسجيل الدخول

تسجيل

Oocyte– Granulosa cell Interaction: Steroids and Gonadotropin Receptors

المؤلف:  Wass, J. A. H., Arlt, W., & Semple, R. K. (Eds.).

المصدر:  Oxford Textbook of Endocrinology and Diabetes

الجزء والصفحة:  3rd edition , p1260-1261

2026-10-24

93

In addition to local peptide hormones, oestrogens, androgens, and progesterone play important role for the regulation of folliculogenesis via specific receptors. Whereas oestrogen receptor- alpha variants and theca cell- specific deletion of oestrogen receptor- alpha leads to premature ovarian failure, deletion of androgen receptors may yield subfertility. Notably, local increment in the concentration of oestrogens induces follicle growth and contributes to the selection of dominant follicle. Dihydrotestosterone, as an androgen, increases FSH receptor expression and provokes oestrogen and progesterone biosynthesis. On the contrary, high levels are associated with follicular atresia.

As might be clearly understood from the aforementioned studies, the full process for detecting the dominant follicle is highly complicated. The total duration of time to reach a preovulatory stage takes around 85 days. Although FSH cannot control every step of folliculogenesis, without any circulating FSH, particularly follicles 2– 5 mm in diameter undergo atresia. During the lifespan of a Graafian follicle, with parallel to the molecular mechanisms given here, the initial change is morphological alteration, as granulosa cells timely become more cuboidal. Nevertheless, for the activation of a primordial follicle, BMP acts as a promoter. Nerve growth factor, brain derived neurotropic factor, neutrophin- 3 and 4/ 5 are various neurotrophins that may alter the early follicular development. After the first awakening of the primordial follicles, FSH receptors also arise in number. The decline in previous luteal phase both in the process of steroidogenesis and production of inhibin A from granulosa cells, a significant rise in concentration of FSH becomes evident particularly during the mid- late luteal phase.