组织切片法观察昆明白小鼠卵丘扩展与卵母细胞成熟的关系

Histologic Study of the Relationship between Cumulus Expansion and Oocyte Maturation in the Kunming White Mouse

本实验应用组织切片法探讨了体内正常生理条件下昆明白小鼠卵巢内卵丘扩展与卵母细胞成熟的关系。初情期前小鼠注射孕马血清促性腺激素 (PMSG) ,4 8h后注射人绒毛膜促性腺激素 (HCG) ,于注射HCG后不同时间取出卵巢进行组织切片。注射 HCG后 1h,卵丘细胞开始扩展 ,此时卵母细胞核膜完整 ,即未发生生发泡破裂 (GVBD) ;注射 HCG后 3h,大部分 (>70 % )大有腔卵泡中卵母细胞发生 GVBD,此时卵丘处于 2级扩展状态。卵丘完全扩展发生在注射 HCG后 9h,而 PB1的排出是从 12 h开始的。结果表明 :在小鼠体内 ,卵丘开始扩展先于卵母细胞成熟 ,但卵母细胞成熟并不需要卵丘完全扩展 ;促性腺激素能促进卵泡发育及卵母细胞成熟 。

The timing of cumulus cell expansion and oocyte maturation was investigated in vivo , using H and E stained paraffin sections of ovary isolated from immature Kunming white mice treated with gonadotropins. One hour after the injection of an ovulatory dose of HCG, expansion of cumulus cells in the outer layer of large antral follicles was observed, but oocyte maturation as evidenced by germinal vesicle breakdown (GVBD) was not evident. Three hours after HCG injection, the majority of oocytes in the large antral follicle (70%) had undergone GVBD, but the cumulus cells were not completely expanded at this time. Cumulus expansion appeared to be completed by 9hr after HCG injection, however, oocyte maturation occurred about 3hr later than cumulus expansion. The results indicate that primary cumulus expansion occurred prior to oocyte maturation, whereas cumulus mass complete expansion is not necessary for maturation of oocyte in vivo.