虹鳟(Salmo gairdneri Richardson)原生殖细胞的光镜和电镜研究

LIGHT AND ELECTRON MICROSCOPIC STUDIES ON PRIMORDIAL GERM CELLS IN satmo GAIRDNERI RICHARDSON

本文应用光镜和电镜研究了虹鳟(Salmo gairdneri Richardson)原生殖细胞(Primordial Germ Cells,PGCs)的细胞学和超微结构特征、起源、迁移和数量变动。结果表明:1)虹鳟PGCs的鉴别特征是细胞体较大、细胞界限清楚,核较大,核仁明显,核膜外或线粒体丛间含有生殖致密体(Germinal Densc Bodies,GDBs);2)PGCs起源于原肠晚期的预定中胚层;3)PGCs向生殖腺原基的迁移是随着胚胎的形态发生运动而进行的被动过程;4)迁移期PGCs的数量为70～90个。研究发现,虹鳟PGCs中的GDBs常位于核膜孔附近,推测它可能来自核质。对虹鳟PGCs的鉴别标准、起源和迁移方式作了讨论。

The cytological and ultrastructural characteristics, origin, migration, and the change in number 'of primordial germ cells (PGCs) in Salmo gitirdneri have been investigated by light and electron microscopy. The results showed that the PGCs were identified by their large size, distinct outline and large nucleus, their path of translocation and the existence of germinal dense bodies (GDBs) near by the nuclear membrane pore; that the PGCs were first recogniz -able in presumptive mesoderm at late gastrula stage; that the PGCs, trans-location was carried out by the morphogenetic movement of embryo; that approximate number of PGCs was from 70 to SO in migration to the gonadal anlage, and no figure of cell division of PGCs was found throughout this period. The identifiable standards, origin, the pattern of migration are discussed.