冻融后小鼠休眠胚胎超微结构的变化

摘要

Objective The aim of this study was to investigate the differences of the cell ultrastucture of normal mouse hatched blastocysts and their dormant ones cultured in vitro after freezing-thawing, and to explore whether the dor-mant embryos have a better anti-freezing shock property than the normal hatched mouse embryos .Methods By transmis-sion electron microscopy , the ultrastructure of these two types of mouse embryos was observed and analyzed .Results By comparative analysis of their ultrastructure , the results showed that the dormant embryos before freezing are being austerity and with lower energy metabolism at a ‘ground state ’ .After freezing-thawing and culture , their cellular structure seemed to be similar to that of the normal embryos cultured in vitro before freezing.However, after freezing-thawing and culture, the number of mitochondria decreased , the nuclei were loose , and their heterochromatin also increased .Conclusions From the ultrastructural observation , compared with the normal mouse hatched embryos , the cellular state of dormant mouse em-bryos after freezing-thawing is more favorable for material storage and energy metabolism , thus, indicating that they have a better anti-freezing property than normal hatched embryos .%目的：从亚细胞超微结构的角度揭示其抗冻能力优于正常孵化胚胎的原因。方法利用透射电子显微镜观察小鼠休眠胚胎与正常孵化期胚胎在细胞连接和各细胞器形态与分布上的差异，以及冻融培养后的变化，并进行相关比较分析。结果通过亚细胞结构对比分析发现：冷冻前小鼠休眠胚胎为紧缩状，处于能量代谢较低的“基态”，通过冻融后培养，细胞器结构恢复与正常孵化胚胎冷冻前相似；而正常孵化胚胎经过冻融后，线粒体数量减少，细胞核松散，异染色质增多。结论小鼠休眠胚胎与正常孵化胚胎冻融后相比，其细胞状态更有利于物质储存及能量代谢，表明小鼠休眠胚胎从亚细胞超微结构的角度比其正常孵化胚胎更具抗冻性。