中文摘要：

目的 研究内皮素-1（ET-1）对小鼠未成熟卵母细胞生发泡破裂（GVBD）、第一极体（PBⅠ）排出的影响。方法 昆明系雌性小鼠生发泡（GV期）卵母细胞分为去卵丘裸卵（DO）组及卵丘卵母细胞复合体（COC）组，在体外培养条件下，观察ET-1对两组GVBD、PBⅠ形成的量效和时效关系。结果 （1）DO在10^-9、10^-8、10^-7、10^-6～mol／LET-1作用3、6、9、12、24h对其成熟分裂无明显影响（P〉0．05）；（2）COC在10^-8mol／LET-1作用6h能显著抑制GVBD率（P〈0．05），在10^-7、10^-6mol／L ET-1作用6h极显著抑制GVBD率（P〈0．01）；在10^-8mol／LET-1作用12h明显抑制PBⅠ率（P〈0．05），10^-7、10^-6mol／L ET-1作用12h极显著抑制PBⅠ率（P〈0、01）。结论 ET-1对COC体外成熟具有抑制作用并呈剂量依赖性，对DO体外成熟无明显影响。

英文摘要：

Objective： To study the effects of endothelin-1 （ET-1） on mouse oocyte germinal vesicle breakdown （GVBD） and extrusion of the first polar body（PBI）. Methods： The mouse cumulus-oocyte complexes （COCs） were collected, and some of them had the cumulus removed（denuded oocytes, DO）. The COCs and DOs were cultured in the medium supplemented with ET-1 at various concentrations（10^-9 mol/L, 10^-8 mol/L, 10^-7 mol/L and 10^-6 mol/L）, respectively, and the rates of GVBD and PBI extrusion were observed at different culture time. Results： The rates of GVBD and PBI extrusion in DO group did not change much when treated with various concentrations of ET-1（P〉0.05）. The GVBD in COC group was significantly inhibited by ET-1 at the concentrations of 10 8 mol/L（P〈0.05）, 10^-7 mol/L and 10^-6 Gmol/L（P〈0. 01, respectively） after six hours of culture. When COCs were cultured for 12 hours, the PBI extrusion was significantly inhibited by ET-1 at the concentrations of 10^-8 mol/L（P〈0.05）, 10^-7 mol/Land 10^-6 mol/L（P〈0.01, respectively）. Conclusion： ET-1 can inhibit the in vitro maturation of mouse COC but not the in vitro maturation of denuded oocytes.