大鼠睾丸生殖细胞凋亡的透射电镜观察

目的 :探索雄性生殖细胞凋亡的超微结构形态变化特征。方法 :用透射电镜对胚胎及生后不同发育阶段SD大鼠睾丸内凋亡生殖细胞的超微结构形态变化进行观察。结果 :SD大鼠胚胎第 15 .5～ 17.5d睾丸原始生殖细胞即有凋亡出现 ,第 19.5d和生后第 1d原始生殖细胞基本没有凋亡 ;生后第 7d精原细胞开始分化增生时伴有较多凋亡 ;生后第 14d精母细胞第一次增殖高峰开始时 ,精母细胞凋亡率较高。此后至成熟均可见凋亡出现 ,主要是精原细胞和精母细胞。电镜下生殖细胞退化时具有典型的细胞凋亡形态特征 ,最后被邻近的支持细胞所吞噬 ,既有单个生殖细胞发生凋亡又有同源生殖细胞同时凋亡。结论 :胚胎及生后不同发育阶段SD大鼠睾丸生殖细胞都有凋亡发生 ,多出现于增殖过程的原始生殖细胞、精原细胞和精母细胞

Investigation of the Apoptosis of Germ Cell in the Testisof the SD Rat by Transmission Electron Microscope

To demonstrate the ultrastructure morphological characteristic in the apoptosis of the male germ cells during development. Methods: We observed the apoptosis of germ cell in the testis of the SD rat during fetal and postnatal development by transmission electron microscope. Results: The apoptosis occured in the primordial germ cells of testis in the 15.5th day post coitum (dpc) and 17.5th dpc; but it didn't occur in the primordial germ cells in the 19.5th dpc and 1 day post partum (dpp). In the 7th dpp there was much apoptosis in the spermatogonia when they began to differentiate. In the 14th dpp. the incidence of apoptosis was high in spermatocytes when their differentiation and proliferation was found at the first peak. Until to adulthood, apoptosis was seen mainly in spermatogonia and spermatocytes. The germ cell's degeneration showed typical morphological characteristic of apoptosis in the electron microscope, and in the final stage, the apoptotic germ cells were phagocytosed by neibouring Sertoli cells. Both single apoptotic germ cell and apoptotic colons of germ cells were observed. Conclusion: Apoptosis occurs in the germ cells in the tesis of SD rat during fetal and postnatal development, and it mainly occurs in the proliferating primordial germ cells, spermatogonia and spermatocytes.