title: The effect of progesterone upon first trimester trophoblastic cell differentiation and human chorionic gonadotrophin secretion.
abstract: The effect of progesterone (P) upon first trimester placental secretion of human chorionic gonadotrophin (HCG) and cellular differentiation was studied using both static and kinetic methods. At 1 microM, P inhibited spontaneous episodic secretion of HCG when given in short pulses (1-4 min) to placental explants in superfusion. Both HCG pulse frequency and amplitude were reduced. At 0.1-0.01 microM P concentrations, the effect of HCG secretion was milder. P also blocked the maximally effective concentration 100 pM of gonadotrophin releasing hormone (GnRH) analogue, a known HCG stimulant, when given together with it for 1 min. This inhibitory effect lasted for 1 h after P administration. Progesterone at 1 microM, added daily for 1 week blocked HCG secretion by isolated trophoblastic cells in static culture. This inhibitory effect lasted until the fifth day. No effect on differentiation and long-term viability was noticed in P-treated cells. Incubation with 0.1-1.0 microM P did not affect HCG secretion by explants after 24 h. In contrast, the effect of 1 microM cortisol or 1 nM oestradiol was stimulatory. In conclusion, P exerts both a rapid and delayed inhibitory effect upon HCG secretion and production. It may do so by counteracting the stimulatory effect of endogenous GnRH on gonadotrophin secretion by the placenta.
authors.affiliation: University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical Center, Department Ob/Gyn, Camden.
authors.forename: E R
authors.initials: ER
authors.lastname: Barnea
authors.forename: D
authors.initials: D
authors.lastname: Feldman
authors.forename: M
authors.initials: M
authors.lastname: Kaplan
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives; D006801:Humans; D006854:Hydrocortisone / Q000494:pharmacology; D010477:Perfusion; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011374:Progesterone / Q000494:pharmacology*; D011863:Radioimmunoassay; D014327:Trophoblasts / Q000166:cytology / Q000187:drug effects*
chemical_list: D006063:Chorionic Gonadotropin; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D004958:Estradiol; D006854:Hydrocortisone