Hypothalamic, pituitary and gonadal regulation of FSH.

FSH is a key reproductive hormone involved in the control of ovarian folliculogenesis and steroidogenesis. Multiple regulatory mechanisms govern the release of FSH. These regulatory mechanisms appear to work in concert to modulate the level, pattern and biological potency of circulating FSH, thereby adjusting the gonadotrophic stimulus to meet the challenge of a changing physiological need. This review (i) summarizes various neuroendocrine, autocrine and paracrine mechanisms involved in the control of FSH production and secretion; (ii) identifies possible mechanisms by which LH and FSH are differentially released from the same gonadotrophs; (iii) considers the means by which changes in the quality of the FSH signal are regulated and the implication of such changes; and (iv) emphasizes how large animal models have helped to advance our understanding of FSH control.