title: Gonadotropin-releasing hormone in the ovary.
abstract: Gonadotropin-releasing hormone (GnRH) plays a pivotal role in the physiology of reproduction in mammals. GnRH acts by binding to the GnRH receptor (GnRHR). In humans, only 1 conventional GnRH receptor subtype (type I GnRH receptor) has been found. In the human genome, 2 forms of GnRH have been identified, GnRH-I (mammal GnRH) and GnRH-II (chicken GnRH II). Both forms and their common receptor are expressed, apart from the hypothalamus, in various compartments of the human ovary. Gonadal steroids, gonadotropins, and GnRH itself controls the regulation of the GnRH/GnRHR system gene expression in the human ovary. The 2 types of GnRH acting paracrinally/autocrinally influence ovarian steroidogenesis, decrease the proliferation, and induce apoptosis of ovarian cells. In this review, the biology of GnRH/GnRHR system in humans, the potential roles of GnRH, and the direct effects of GnRH analogues in ovarian cells are discussed.
authors: Department of Physiology, School of Medicine, Democritus University of Thrace, Dragana, Greece.
authors: Chryssa
authors: C
authors: Metallinou
authors: Byron
authors: B
authors: Asimakopoulos
authors: Andreas
authors: A
authors: Schröer
authors: Nikos
authors: N
authors: Nikolettos
mesh_terms: D000818:Animals; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000235:genetics / Q000502:physiology*; D006801:Humans; D010053:Ovary / Q000502:physiology*; D020033:Protein Isoforms; D011966:Receptors, LHRH / Q000502:physiology
chemical_list: D020033:Protein Isoforms; D011966:Receptors, LHRH; D007987:Gonadotropin-Releasing Hormone