目的：探讨人胎儿卵泡的发育形成过程及卵细胞凋亡情况。方法收集2013年1~12月于广东省计划生育科学技术研究所行中期妊娠及晚期妊娠(24~32周)引产的女性胎儿卵巢组织18例。其中24~27周(孕中期)胎儿卵巢组织8例,28~32周(孕晚期)胎儿卵巢组织10例。采用免疫组化苏木精-伊红(HE)染色及原位末端标记法(TUNEL),观察胎儿卵巢卵泡发育及形成过程及该过程中卵细胞凋亡情况。结果 HE染色显微镜下观察,孕中期胎龄卵巢原始卵母细胞较多,卵巢间质少,颗粒细胞较少。随着胎龄的增加,颗粒细胞逐渐增多；围绕卵母细胞,原始卵泡逐渐形成并开始增多,卵母细胞数量减少。孕晚期原始卵母细胞明显减少,原始卵泡形成,数量进一步增多,随着孕龄增加,原始卵泡愈发完整。 TUNEL染色观察见阳性凋亡细胞多见于未形成卵泡的卵母细胞,卵细胞周围的颗粒细胞在孕晚期可见少许凋亡,卵泡内卵细胞未见阳性染色。孕中期卵巢卵母细胞凋亡明显多于孕晚期,且凋亡主要发生于未形成原始卵泡的卵母细胞。结论胎儿卵巢发育过程中,原始卵母细胞数量逐步减少,原始卵泡形成,其发育过程中原始卵母细胞不断发生凋亡,导致生殖细胞丢失。%Objective To investigate the development and apoptosis of the oocyte during human fetal development.Methods Ovarian tissues from 18 fetuses (aged 24-32 weeks) from January 2013 to December 2013 in Guangdong Family Planning Institute of Science and Technology were obtained, including 8 fetuses aged 24-27 weeks (midpregnancy) and 10 fetuses aged 28-32 weeks (late-pregnancy).The morphology and development of oocyte and the occurrence of oocyte apop-tosis during human fetal follicular development were examined using HE-staining and TUNEL method. Results Micro-scope observation after HE-staining, the ovarian tissues in the midpregnancy had more oocytes than the late-pregnan-cy, less ovarian stroma and granulosa cells. The granulosa cells increased gradually, and primordial follicles grown up and began to accumulate around the oocytes during human fetal development, while the number of oocytes decreased. The number of original oocytes decreased significantly in late-pregnancy, Primordial follicle grown up and began to accumulate with the increase of gestational age, primitive follicles more complete. TUNEL stained showed that, apoptot-ic cell was easily found in follicular oocytes that had not formed the follicle, granule there were a few apoptotic cells around egg cells in the late-pregnancy, no egg cell in follicle was positive stained. The number of apoptotic cell in midpregnancy was more than late-pregnancy, and apoptosis mainly happened on the oocytes that had not formed a pri-mordial follicle. Conclusion The original oocytes become less during the human fetal follicular development, it is caused by the oocyte apoptotosis, the original follicular is formed in the fetal ovar of the late-pregnancy.
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