title: Müllerian inhibiting substance as oocyte meiosis inhibitor.
abstract: Müllerian inhibiting substance (MIS) inhibited the resumption of meiosis in both denuded and cumulus cell-enclosed rat oocytes in vitro. Spontaneous germinal vesicle breakdown was prevented in both types of oocytes treated by a purified MIS preparation at protein concentrations of 15 micrograms to 150 pg/ml. The inhibiting effect of MIS on the resumption of meiosis was dose dependent, reversible and cyclic AMP independent. Neither follicular-stimulating hormone, luteinizing hormone, progesterone, estradiol, nor testosterone acted significantly to influence MIS-mediated inhibition of rat oocyte maturation. In contrast, MIS had no influence on meiosis in the mouse, where other protein has been reported to inhibit the cumulus cell-enclosed oocyte in a cyclic AMP-dependent fashion. Thus MIS may be yet another inhibitor of oocyte meiosis, acting in the rat by a mechanism different from those inhibitors known, in the mouse ovary, to exert their effect in a cyclic AMP-dependent manner.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D054304:Anti-Mullerian Hormone; D003994:Bucladesine / Q000494:pharmacology; D005260:Female; D006023:Glycoproteins; D012739:Gonadal Steroid Hormones / Q000494:pharmacology; D006062:Gonadotropins / Q000494:pharmacology; D006131:Growth Inhibitors; D008540:Meiosis / Q000187:drug effects; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D009866:Oogenesis / Q000187:drug effects; D051381:Rats; D013735:Testicular Hormones / Q000502:physiology*
chemical_list: D006023:Glycoproteins; D012739:Gonadal Steroid Hormones; D006062:Gonadotropins; D006131:Growth Inhibitors; D013735:Testicular Hormones; D003994:Bucladesine; D054304:Anti-Mullerian Hormone; D015056:1-Methyl-3-isobutylxanthine