摘要
尽管在母亲的老化和不孕的氧化应力的角色被建议了,内在的机制充分没被理解。现在的学习被设计在氧化应力下面在中期 II (MII ) 卵母细胞决定在 mitochondrial 功能和锭子稳定性之间的关系。MII 老鼠卵母细胞当面与 H2O2 被对待或渗透转变毛孔(PTP ) 的缺席块 ers cyclosporin A (CsA ) 。另外,抗氧化剂 N-acetylcysteine (NAC ) , F0/F1 synthase 禁止者 oligomycin A,线粒体 uncoupler 羰基氰化物 4-trifluoro-methoxyphenylhydrazone (FCCP ) 或加 2.5 公里 Ca2+(Th+2.5 公里 Ca2+) 的 thapsigargin 在机械学的研究被使用。卵母细胞锭子和染色体的词法分析被执行并且 mitochondrial 膜潜力(DeltaPsim ) ,细胞质的免费的钙集中([Ca2+] c ) 并且在卵母细胞以内的细胞质的 ATP 内容也是 assayed。在一时间 -- 并且 H2O2 剂量依赖者举止,锭子在卵母细胞以后被发现的 meiotic 的混乱与 H2O2 被对待,它被预告的处理与 NAC 阻止。H2O2 的管理导致了 DeltaPsim 的驱散,的增加[Ca2+] 在细胞质的 ATP 的 c 和减少铺平。到 H2O2 处理的卵母细胞的这些有害回答能被孵化前与 CsA 堵住。类似于驱散的 H2O2,两 oligomycin A 和 FCCP DeltaPsim,减少的细胞质的 ATP 内容和拆卸的 MII 卵母细胞锭子,当时高[Ca2+] c 独自没在锭子形态学上有效果。在结论,在导出线粒体的 ATP 的减少可以在氧化应力期间引起老鼠 MII 卵母细胞锭子的拆卸,大概由于 mitochondrial PTP 的开始。
Although the role of oxidative stress in maternal aging and infertility has been suggested, the underlying mechanisms are not fully understood. The present study is designed to determine the relationship between mitochondrial function and spindle stability in metaphase II (MII) oocytes under oxidative stress. MII mouse oocytes were treated with H2O2 in the presence or absence of permeability transition pores (PTPs) blockers cyclosporin A (CsA). In addition, antioxidant N-acetylcysteine (NAC), F0/F1 synthase inhibitor oligomycin A, the mitochondria uncoupler carbonyl cyanide 4-trifluoro- methoxyphenylhydrazone (FCCP) or thapsigargin plus 2.5 mM Ca^2+ (Th+2.5 mM Ca^2+) were used in mechanistic studies. Morphologic analyses of oocyte spindles and chromosomes were performed and mitochondrial membrane potential (AWm), cytoplasmic free calcium concentration ([Ca^2+]c) and cytoplasmic ATP content within oocytes were also assayed. In a time- and H202 dose-dependent manner, disruption of meiotic spindles was found after oocytes were treated with H202, which was prevented by pre-treatment with NAC. Administration of H2O2 led to a dissipation of AWm, an increase in [Ca^2+]c and a decrease in cytoplasmic ATP levels. These detrimental responses of oocytes to H2O2 treatment could be blocked by pre-incubation with CsA. Similar to H2O2, both oligomycin A and FCCP dissipated AWm, decreased cytoplasmic ATP contents and disassembled MII oocyte spindles, while high [Ca^2+]c alone had no effects on spindle morphology. In conclusion, the decrease in mitochondria-derived ATP during oxidative stress may cause a disassembly of mouse MII oocyte spindles, presumably due to the opening of the mitochondrial PTPs.
