山溪鲵卵黄发生的显微与超微结构

摘要

The microstructure and ultrastructure of several different developmental stages of the oocytes of the salamander Batrachuperus pinchonii were observed. Special attention was paid to changes in the organelles related to vitellogenesis. The results suggest that the nuage forms a focus of aggregation for membraneous organelles. The mitochondria can develop into the precursors of yolk platelets. Both endocytic vesicles and Mylins body play a key role in vitellogenin endocytosis. Vitellogenesis in nonmammalian verteberate species results from the harmonious activity of the ooplasm and the organelles. Vitellogenesis is the consequence of whole cell activity, therefore intracellular pathways involved in vitellogenesis are diverse rather than unitary. The development of oocytes in different species reveal different patterns, a result of differential expression of intracellular pathways during vitellogenesis.%用光镜和透射电镜观察了山溪鲵(Batrachuperus pinchonii)不同发育时期卵母细胞的显微与超微结构,特别注意了与卵黄发生相关的细胞器变化.结果表明,类核周体为线粒体、高尔基体、内质网等膜性细胞器聚集的场所;线粒体自身也可演变成卵黄前颗粒,参与构成卵黄小板的成分;吞饮泡和髓样小体是卵母细胞利用外源卵黄物质的中间媒介.经过与其他动物卵黄发生过程相比较,认为非哺乳脊椎动物卵黄发生是卵母细胞在多种细胞器参与下整体活动的结果,不是经由单一的模式或途径形成,因此呈现发生上的多元化;不同物种在卵黄发生中分别采取与各自相适应的模式或途径.