哺乳动物卵母细胞玻璃化冷冻保存的研究进展

Progress on Vitrification of Oocytes from Mammalian Species

综述了近年来关于哺乳动物卵母细胞玻璃化冷冻保存的研究进展,并对这项技术的发展前景进行展望。重点讨论了影响哺乳动物卵母细胞玻璃化冷冻保存的几种因素,包括冷冻保护剂的种类和浓度、冷冻方法和卵母细胞所处的发育阶段等,以及冷冻过程中细胞膜、微丝、微管、皮质颗粒、纺锤体和线粒体等出现的损伤。目前,玻璃化冷冻法存在的最主要问题是冷冻过程中造成超微结构不可逆转的损伤影响胚胎发育,亟待解决。

In comparison to the cryopreservation of preimplantation embryos, cryopreservauon of oocytes from most mammalian species has been more challenging due to their extreme sensitivity to suboptimal conditions during the cryopreservation process. Recent attempts to find a successful cryopreservation technique for oocytes have been directed to the use of vitrification by rapid cooling. They allow oocytes to be placed directly or preequilibrium for several minutes into the cryoprotectant and then plunged directly into liquid nitrogen. At present, vitrification techniques have entered the mainstream of animal reproduction and many studies have been conducted in this area in recent years. In this paper, recent research on vitrification of oocytes were reviewed, with emphasis on the effects of type and concentration of cryoprotect, cryopreservation methods and the meiotic stages of oocytes, and changes in the ultrastructure of the cell membrane, cytoskeleton, mitochondria, cortical granules and spindle. In conclusion, studies have shown that vitrification at the ultrarapid cooling rate is a promising approach for oocytes cryopreservation, but many problems remain to be solved on the damages of ultrastructure during cryopreservation process.