摘要
目的研究北草蜥的精子形成过程。方法以2·5%戊二醛和1%锇酸双重固定,常规制作石蜡切片和超薄切片,光镜和透射电镜观察。结果北草蜥精子形成过程主要有核逐渐延长、染色质浓缩、顶体形成、线粒体逐步发达与融合、细胞质消除与鞭毛形成等。可分为4个时期:时期Ⅰ,精子细胞前顶体囊泡移至核膜时,核膜凹陷形成封闭的顶体囊泡,囊泡底部靠近核膜有一电子致密的顶体颗粒,在1个薄层有颗粒的胞质中形成顶体下颗粒,将顶体颗粒和核膜连接起来;时期Ⅱ,精子细胞顶体囊泡扁平,细胞核延长,染色质浓缩成短丝状的染色质纤维;时期Ⅲ,精子细胞核进一步延长,染色质纤维变粗变长,并沿核纵轴方向有序排列,近端中心粒及尾部开始出现;时期Ⅳ,Sertoli细胞质内纵行微管出现,至精子释放前消失,精子细胞顶体发育完全,终环形成,核内染色质纤维浓缩至最大限度,呈高电子致密度的均质状态。结论北草蜥精子形成过程中细胞核及细胞器的超微结构变化在有鳞类蜥蜴分类上具有重要意义。
Objective We studied the uhrastructure of seprmiogenesis of Takydromus septentrionalis. Methods After double fixed with 2.5 % glutaric dialdehyde and 1% osmic acid, we observed the paraffin section and uhrathin section by light microscope and transmission electron microscopy respectively. Results There is a series of considerable changes in morphology and structure during the spermiogenesis of Takydromus septentrionalis. These changes include gradual nuclear elongation, chromatin condensation,formation of acrosome, development and fusion of mitochondria, cytoplasmic sloughing and flagellar formation. The course of spermiogenesis can be derided into four stages： Stage Ⅰ ,the spermatid nucleus concaved when the preacrosomal vesicle reached the nucleus,increasingly,acrosomal vesicle came into being and acrosomal granules appeared at the bottom of acrosomal vesicle,in a thin layer of granular cytoplasm, the subacrosomal granule was formed,it contacts both the acrosomal granule and the outer nuclear membrane; Stage Ⅱ , the spermatid acrosomal vesicle flattened and chromatin condensed into fibers like short filaments and the nucleus prolonged ; Stage Ⅲ, the spermatid nucleus went on prologing and the chromatin fibers in it went on condensing and the chromatin fibers was put in a order of parallel to the longitudinal axis of the nucleus. The proximal centriole and flagellum appeared, Stage Ⅳ,, the longitudinal microtubules in Sertoli cells cytoplasm appeared around the sperm head and disappeared till sperm was mature. The acrosemal complex of spermatid was well-developed, and annulus was appeared. The nuclear chromatin condensed to the greatest extent and the nucleus was electron-dense. Conclusion It has great significance of nucleus and cell organelle as taxonomic character of Squamate lizard in the uhrastructure of spermiogenesis of Takydromus septentrionalis.
出处
《解剖学报》
CAS
CSCD
北大核心
2005年第4期436-441,共6页
Acta Anatomica Sinica
基金
温州市新世纪551人才工程基金资助(2004108)
温州师范学院科研项目基金(2003Z18)资助
