性成熟前小鼠生精细胞的发育过程

用光镜、电镜观察了生后 1～ 1 8d昆明白小鼠的生精上皮。结果显示 ,生后 1～ 3 d,曲细精管内只有生殖母细胞和支持细胞 2类形态结构截然不同的细胞 ,前者位于管中部 ;生后 4～ 5d,少数生殖母细胞已附着在基膜上 ;生后 6～ 7d,原始 A型精原细胞大量出现并附着在基膜上 ;生后 8d,A型精原干细胞大量出现 ,B型精原细胞开始出现 ;生后 1 0 d,B型精原细胞大量出现 ;生后 1 2～ 1 3 d,前初级精母细胞出现 ,少数曲细精管的管腔开始出现 ;生后 1 4～ 1 5d,多数曲细精管管腔基本形成 ,前初级精母细胞大量出现。本试验的结果表明 ,7～ 8d小鼠的睾丸最适于分离精原干细胞

Developmental Process of Germ Cells in Prepuberal Mouse

The seminiferous epithelium of the mouse of 1 18 d old was observed under light and electron microscope. The results showed that: by 1 3 d after birth, there were only two distinct cell types, gonocytes and Sertoli cells in the tubulus. The former was evident in the center of the cords. By 4 5 d, a small number of gonocytes was attached to the basement membrane. A large number of premitive type A spermatogonia was present and attached to the basement membrane at 6 7 d. By 8 d, type A spermatogonial stem cells were present at large number and type B spermatogonia began to appear. By 10 d, a large quantity of type B spermatogonia was present. Pre primary spermatocytes were present and a few tubular lumen began to come into being at 12 13 d. By 14 15 d, many seminiferous cords had acquired a lumen and pre primary spermatocytes appeared at large number. The results indicated that the testis of 7 8 d old mouse was fitted to isolate spermatogonial stem cells.