title: [The effects of no synthase blocker, no donor, and exogenous prostaglandins E2 and F2alpha on murine oocytes].
abstract: Nitric oxide (NO) has emerged as one of several important intraovarian regulatory factors. Although the importance of NO has been demonstrated during gestation, its role in oocyte meiotic maturation (MM) is incompletely clear. In this context, the effects of nitric oxide synthase (NOS) blocker (N-omega-mono-methyl L-arginine, L-NMMA), NO donor (sodium nitroprusside, Na-NP), and exogenous prostaglandins (PGs) F2alpha and E2 on the MM of oocytes in mice have been studied. The exogenous PGs in a dose of 3.00 microg/kg inhibited the MM of murine oocytes. The effect of L-NMMA on the MM of oocytes was studied for the first time depending on the size of a follicle from which they were isolated. The maximum inhibition was observed for oocytes isolated from small follicles. Na-NP induced an increase in the number of oocytes from small (p < 0.01) and medium (p < 0.05) follicles, capable of forming polar bodies after a 20-h cultivation. The introduction of PG F2alpha to the test animals pretreated with L-NMMA potentiated the inhibition of MM. The NO donor decreased the inhibiting effect of PG F2alpha on the MM of oocytes isolated from small (p < 0.05) and medium (p < 0.05) follicles. The results confirm that NO/NOS ovarian system is involved into the mechanism of the PG action on the MM of murine oocytes and, probably, that NO is involved into the general mechanism of PG activity. In this case, PG, F2alpha can operate through nongenomic stimulation of membrane/endocellular mediators, where NO also acts as a mediator.
authors.forename: T Iu
authors.initials: TIu
authors.lastname: Voznesenskaia
authors.forename: T V
authors.initials: TV
authors.lastname: Blashkiv
mesh_terms: D000818:Animals; D015237:Dinoprost / Q000494:pharmacology*; D015232:Dinoprostone / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D008540:Meiosis / Q000187:drug effects; D051379:Mice; D008808:Mice, Inbred CBA; D009569:Nitric Oxide / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D009599:Nitroprusside / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects* / Q000502:physiology; D019323:omega-N-Methylarginine / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D020030:Nitric Oxide Donors; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D015237:Dinoprost; D019001:Nitric Oxide Synthase; D015232:Dinoprostone