Hypothalamic LH-Releasing Hormone: Chemistry, Physiology and Effect in Humans

There is now good evidence that the secretion of LH and FSH from the anterior pituitary gland is controlled principally by the central nervous system and a feedback system, involving sex steroids [1, 2]. The hypothalamus stimulates the secretion of follicle stimulating hormone (FSH), luteinizing hormone (LH) and other pituitary hormones by releasing regulatory substances into portal blood flowing from the median eminence region into the pars distalis [3, 4]. Table 1 lists the known hypothalamic hormones and the new nomenclature we have proposed for them [4]. In this report we shall be concerned only with LH-releasing hormone (LH-RH) and FSH-releasing hormone (FSH-RH). Their function is to augment the secretion of LH and FSH.