Mechanisms underlying oocyte activation and postovulatory ageing
Mechanisms underlying oocyte activation and postovulatory ageing
复制标题
DOI：
10.1530/rep.0.1240745
复制
发表时间：
2002-12-01
期刊：
影响因子：
3.8
通讯作者：
Smyth, J
中科院分区：
文献类型：
--
作者：
Fissore, RA;Kurokawa, M;Smyth, J
哺乳动物卵母细胞在卵子发生过程中经历了显著的生长，并在排卵前立即经历了广泛的细胞质和核的修饰，这一过程通常被称为卵母细胞成熟。这些变化旨在最大限度地促进受精后的发育成功。精子进入卵母细胞，发生在排卵后几个小时，引发细胞内游离钙([Ca~(2+)](I))的长期振荡，这是卵母细胞激活的所有事件和发育程序的启动，通常最终导致幼崽的出生。然而，在成熟过程中发生的细胞和分子变化是短暂的，并表现出迅速的恶化。此外，卵母细胞在输卵管(或培养中)长期停留后受精，会启动不同的发育程序，其特征是碎裂、程序性细胞死亡和异常发育。由于[Ca~(2+)](I)振荡可以触发哺乳动物卵母细胞的两种发育程序，因此本文综述了精子可能用来启动这些持续性[Ca~(2+)](I)反应的机制之一(S)，以及可能导致哺乳动物卵母细胞老化后排泄后细胞碎裂的细胞和分子变化。
Mammalian oocytes undergo significant growth during oogenesis and experience extensive cytoplasmic and nuclear modifications immediately before ovulation in a process commonly referred to as oocyte maturation. These changes are intended to maximize the developmental success after fertilization. Entry of a spermatozoon into the oocyte, which occurs a few hours after ovulation, initiates long-lasting oscillations in the free intracellular calcium ([Ca2+](i)) that are responsible for all events of oocyte activation and the initiation of the developmental programme that often culminates in the birth of young. Nevertheless, the cellular and molecular changes that occur during maturation to optimize development are transient, and exhibit rapid deterioration. Moreover, fertilization of oocytes after an extended residence in the oviduct (or in culture) initiates a different developmental programme, one that is characterized by fragmentation, programmed cell death, and abnormal development. Inasmuch as [Ca2+](i) oscillations can trigger both developmental programmes in mammalian oocytes, this review addresses one of the mechanism(s) possibly used by spermatozoa to initiate these persistent [Ca2+](i) responses, and the cellular and molecular changes that may underlie the postovulatory cellular fragmentation of ageing mammalian oocytes.