3种鲈形目鱼类精子发生早期的超微结构研究

采用透射电镜技术,研究了3种鲈形目鱼类褐菖鲉Sebastiscus marmoratus、黑鲷Sparus macrocephalus及平鲷Rhabdosargus sarba(Forskal)精子发生早期精原细胞、初级精母细胞及次级精母细胞的超显微结构变化。结果表明,3种鱼生精细胞形态结构及代谢活动变化主要体现在核的变化、线粒体数目与结构的变化及高尔基体和溶酶体的行为变化。3种鱼核的变化基本一致:细胞核由近圆形或椭圆形转变为多角形;核质逐渐浓缩;核仁从明显结构至完全消失。褐菖鲉精原细胞时期线粒体分布较多,并出现拟染色质与线粒体相粘附;而平鲷与黑鲷精原细胞时期的线粒体分布较少,无拟染色质。3种鱼高尔基体与溶酶体的变化也有相似性。黑鲷的初级精母细胞中还观察到典型的环层状的髓样小体的结构。

THE ULTRASTRUCTURE OF THREE PERCIFORMES DURING PRIMARY SPERMATOGENESIS

The ultrastructure of spermatogonias,primary spermatocytes and secondary spermatocyte in Sebastiscus marmoratus,Sparus macrocephalus and Rhabdosargus sarba (Forskai) was studied in transmission electron microscopy. Difference was shown in nucleus form and the number of mitochondria,and the secretion of Golgi body and morphological differentiation of lysosome were also observed. The deference in nucleus form depended on developmental and physiological activities. In early spermatogenesis,nuclear structure of three species is very similar. The shape of spermatocytes changed from round or ellipse to polygon. Chromatins concentrated gradually and dispersed in karyotin or inner karothece in spermatocytes stage. Nucleolus shrank,dispersed,and finally disappeared. In spermatocytes stage,nuclei membrane vesiculation was significant and the number of nucleopore complexes increased,which are good for transporting RNA and ribosomes into cytoplasm to ensure material supply for synthesizing proteins. Some similar features were shown in ultrastructure of organelles of S. marmoratus,S. macrocephalus and R. sarba (Forskai) during primary spermatogenesis. The mitochondria with developed ridges dispersed sharply in spermatocytes stage,and they were small and the cristae were undeveloped in spermatogonia stage. The lysosomes were in shape of vesicle in high electron-density. Chromatoid bodies linking mitochondrins were observed only in the cytoplasm of S. marmoratus,and no Golgi body was found in cytoplasm of S. marmoratus. Typical Golgi body and myelinoid body were observed in cytoplasm of S. macrocephalus.