title: Activin inhibition of estradiol and progesterone production in porcine granulosa cells.
abstract: Two studies evaluated the influence of activin on steroidogenesis in cultured porcine granulosa cells obtained at various stages of differentiation. In granulosa cells isolated from 1- to 3-mm follicles, obtained at random stages of the estrous cycle, treatment with activin or transforming growth factor beta (TGF beta) decreased progesterone production during the first 48 h of culture, but neither had an effect on estradiol production. One-half of these cells received FSH treatment at 48 h, and at 96 and 144 h of culture FSH increased estradiol and progesterone production. Activin or TGF beta reduced, in a dose-dependent manner, both basal and FSH-stimulated production of both steroids. In the second study, granulosa cells were obtained during follicular growth associated with weaning and were separated into two subpopulations (weakly associated [WA] and tightly bound [TB]). Estradiol production in culture increased with time after weaning. Tightly bound cells produced more estradiol than WA cells and maintained FSH-stimulated estradiol production, whereas production of progesterone increased in both cell types after treatment with FSH. Activin depressed FSH-stimulated estradiol production in TB cells and depressed FSH-stimulated progesterone production in both cell types. These results clearly indicate that activin depresses in vitro steroidogenesis by granulosa cells from antral, porcine follicles; thus, activin may participate in atresia of antral follicles of this species.
authors.affiliation: USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Ford
authors.forename: H J
authors.initials: HJ
authors.lastname: Howard
mesh_terms: D028341:Activins; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000032:analysis / Q000378:metabolism*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006107:Granulosa Cells / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D006133:Growth Substances / Q000494:pharmacology*; D007265:Inhibins / Q000494:pharmacology*; D011374:Progesterone / Q000032:analysis / Q000378:metabolism*; D011863:Radioimmunoassay / Q000379:methods / Q000662:veterinary; D013552:Swine / Q000378:metabolism*; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000494:pharmacology
chemical_list: D006133:Growth Substances; D016212:Transforming Growth Factor beta; D028341:Activins; D011374:Progesterone; D004958:Estradiol; D007265:Inhibins; D005640:Follicle Stimulating Hormone