title: The hypothalamic-pituitary-adrenal and the hypothalamic- pituitary-gonadal axes interplay.
abstract: Vertebrates respond to stress with activation of the hypothalamic-pituitary-adrenal (HPA) axis, the adrenergic and the autonomic nervous systems. The principal central nervous system regulators of the HPA axis are corticotropin releasing hormone (CRH) and antidiuretic hormone (AVP). Apart from in the central nervous system, CRH has been found in the adrenal medulla, ovaries, myometrium, endometrium, placenta, testis and elsewhere. The activation of the HPA axis during stress affects all body systems. The reproductive axis is inhibited by the HPA axis for the sake of saving energy. The changes to the hypothalamic-pituitary-gonadal (HPG) axis during stress are species-specific, and depend on the type and duration of the stimulus. Several conditions may be associated with altered regulation of the HPA axis. Polycystic ovary syndrome, anorexia nervosa and pregnancy in the third trimester are all characterized by HPA axis activation. In contrast, during the postpartum period, HPA axis suppression is implicated in the "postpartum blues". The actions of CRH are also essential in fetal development and neonatal survival.
authors.affiliation: Endocrine Unit, Second Department of Obstetrics and Gynecology, Aretaieion Hospital, Athens University Medical School, Athens. mastorak@mail.kapatel.gr
authors.forename: George
authors.initials: G
authors.lastname: Mastorakos
authors.forename: Maria G
authors.initials: MG
authors.lastname: Pavlatou
authors.forename: Maria
authors.initials: M
authors.lastname: Mizamtsidi
mesh_terms: D000293:Adolescent; D003346:Corticotropin-Releasing Hormone / Q000502:physiology; D005260:Female; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D008297:Male; D010053:Ovary / Q000502:physiology; D010913:Pituitary-Adrenal System / Q000502:physiology*; D049590:Postpartum Period; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology*; D013312:Stress, Physiological / Q000503:physiopathology; D013737:Testis / Q000502:physiology; D014667:Vasopressins / Q000502:physiology
chemical_list: D014667:Vasopressins; D003346:Corticotropin-Releasing Hormone