title: Endothelin-1 and endothelin-3 stimulate ovarian steroidogenesis.
abstract: The possible direct involvement of endothelin (ET) in preovulatory follicular steroidogenesis was investigated in vitro. Follicular development in immature rats was induced by pregnant mare's serum gonadotropin (PMS). Twenty-four and 48 h after PMS injection, ovarian follicles were incubated in vitro with or without 4 x 10(-11) to 4 x 10(-5) M endothelin-1 (ET-1) or endothelin-3 (ET-3) for 2 h, or perifused in vitro with 4 x 10(-7) M of ET-1 or ET-3 for 3 h. In the incubation study, ET-1 and ET-3 significantly stimulated progesterone, testosterone, and 17 beta-estradiol production by follicles 24 and 48 h after PMS injection. Progesterone, testosterone, and 17 beta-estradiol were increased in a dose-dependent manner by 4 x 10(-11) to 4 x 10(-6) M ET-1 or ET-3; in the case of ET-3, this increase occurred only at 24 h after PMS injection. In addition, ET-1 stimulated ovarian steroid production more effectively than ET-3. In addition to their effects on ovarian steroidogenesis, both ET-1 and ET-3 increased tissue cyclic adenosine-3',5'-monophosphate (cyclic AMP) production. The steroidogenic effect of ET-1 or ET-3 was most pronounced by follicles 48 h after PMS injection. In the perifusion experiment, ET-1 and ET-3 also stimulated progesterone, testosterone, and 17 beta-estradiol secretion. These indicate the involvement of ET-1 or ET-3 in the regulation of ovarian differentiation by stimulating steroidogenesis, at least partially through the mediation of cyclic AMP.
authors.affiliation: Department of Obstetrics and Gynecology, University of Tsukuba, Ibaraki, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Usuki
authors.forename: T
authors.initials: T
authors.lastname: Saitoh
authors.forename: N
authors.initials: N
authors.lastname: Suzuki
authors.forename: C
authors.initials: C
authors.lastname: Kitada
authors.forename: K
authors.initials: K
authors.lastname: Goto
authors.forename: T
authors.initials: T
authors.lastname: Masaki
mesh_terms: D000818:Animals; D016232:Endothelins / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D066298:In Vitro Techniques; D010053:Ovary / Q000187:drug effects / Q000378:metabolism*; D011374:Progesterone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013256:Steroids / Q000096:biosynthesis*; D013268:Stimulation, Chemical; D013739:Testosterone / Q000494:pharmacology
chemical_list: D016232:Endothelins; D006064:Gonadotropins, Equine; D013256:Steroids; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol