Cell surface-binding sites for progesterone mediate calcium uptake in human sperm

摘要: Recent studies (e.g. Blackmore, P. F., Beebe, S. J., Danforth, D. R., and Alexander, N.) (1990) J. Biol. Chem. 265, 1376-1380) have shown that in human sperm, progesterone produces a rapid increase intracellular free calcium ([Ca2+]i) an induction of the acrosome reaction Osman, R. A., Andria, M. L., Jones, A. D., Meizel, (1989) Biochem, Biophys. Res. Commun. 160, 828-833). In this study, location receptors on cell surface sperm was identified using immobilized bovine serum albumin (BSA) (progesterone 3-(O-carboxymethyl)oxime:BSA) as well its 3-O-carboxymethyloxime derivative. Using fluorescence microscopy, BSA-fluorescein isothiocyanate to be excluded from intact thus validating use 3-(O-carboxymethyl)oxime:BSA identify surface-binding sites for progesterone. The derivative rapidly increased [Ca2+]i were full agonists, although they approximately 1.5 orders magnitude less potent than They also displayed identical time course progesterone, entire due influx Ca2+. This progesterone-mediated response different steroid receptor characteristics since very inhibitors genomic responses, RU38486 ZK98.299, ineffective at inhibiting [Ca2+]i. Also synthetic progestins megestrol, medroxyprogesterone acetate, norgestrel, norethynodrel, norethindrone, R5020, cyproterone acetate did not mimic effects It is proposed distinct nongenomic exists sperm.