我国海域耳鲍(Haliotis asinisne)精子发生的超微结构研究

应用透射电子显微镜技术研究了我国海域耳鲍精子发生的全过程。结果表明,耳鲍精原细胞呈近椭圆形,染色质分布较均匀,线粒体较少;初级精母细胞较大,染色质凝聚成小块状,线粒体增多;次级精母细胞较初级精母细胞小,线粒体较多,部分线粒体发生融合,呈扁囊状。分化早期精细胞染色质凝聚成团块状,多数贴附于核膜内面,胞质中出现前顶体颗粒。分化中期精细胞染色质继续凝聚成较大的团块,线粒体在核的一端融合,形成数量少、体积大的线粒体,前顶体颗粒形成圆形外膜明显的前顶体。分化后期精核由近圆形变成长桶状,核内染色质凝聚并均质化,前顶体泡化发育成顶体,鞭毛形成,精细胞分化成精子。成熟精子为鞭毛型精子,由头部、中段和尾部(鞭毛)3部分组成。

ULTRASTRUCTURAL STUDY ON SPERMATOGENESIS OF ABALONE HALIOTIS ASININE LINNAEUS IN THE CHINA SEA

For promoting and improving mariculture of Haliotis asinine Linnaeus, an economically important nutrient abalone that grows fast in high yield, spermatogenesis of the abalone collected in the South China Sea near Hainan was studied using transmission electron microscopy (TEM). The results showed that the spermatogonium was oval with few mitochondria. The chromatin was relatively dispersed. The primary spermatocyte was larger than the spermatogonium;its chromatin became denser and lied at one side of the nucleus;the number of mitochondria increased. The secondary spermatocyte was usually smaller than the primary spermatocyte, many mitochondria merged into flat capsules. The differentiation of spermatid was complicated and could be divided into 3 stages in terms of acrosome evolvement. In the early stage, chromatin agglutinated into lumps and most of them were attached to the internal surface of nuclear membrane;the proacrosomic granule appeared in the cytoplasm;the centriole moved to the posterior extremity of nucleus, and mitochondrion located at one side of the nucleus. In the middle stage, the chromatin continued to agglutinate into bigger lumps, the mitochondria fused at one side of nucleus and formed a few big mitochondria complexes whose pro-acrosomic granule developed into a pre-acrosome that was round and surrounded by plasmalemma in homogeneously high electron density. In the late stage, the nucleus changed in shape from round to long ellipse with condensed and homogenized chromatin, the pre-acrosome approached to the nucleus, alveolated, and developed into acrosome. 5 cystiform mitochondria surrounded the centriole, flagellum formed, and at last the spermatid altered into spermatozoon. A mature spermatozoon was typical hauch-sperm, including a head, middle sector and tail (flagellum). The axoneme of flagellum featured in 9 2 microtubular pattern.