大鳞副泥鳅精子结构研究

Study on the structure of Paramisgurnus daryanus spermatozoa

用光学显微镜和透射电子显微镜对大鳞副泥鳅精子的结构进行研究。结果表明,大鳞副泥鳅的精子主要分为头部、中段和尾部;头部无顶体,在光学显微镜下近圆形,在透射电子显微镜下纵切亦近圆形,主要由细胞核组成,核内染色质致密,核内有核空泡,核外可见清晰核膜,核外可见细胞质,细胞质很少且紧贴细胞核,细胞质外是质膜,质膜在细胞质外呈波浪状;头部后端有一较浅的植入窝,约占核的1/4,植入窝的长轴几乎与细胞核的长轴平行,植入窝内有中心粒复合体;精子的中片与头部无明显分割,位于头部的后方,由中心粒复合体和袖套组成,袖套两边不对称,中心粒复合体由近端中心粒和远端中心粒组成,近端中心粒与远端中心粒之间呈一钝角;精子尾部无侧鳍,可分为主段和末段,尾部主段具有典型的"9+2"的轴丝结构。精子头长为(1.79±0.28)μm,中片长为(1.86±0.42)μm,尾长为(28.06±2.78)μm,全长为(31.65±2.82)μm。

Structure of Paramisgurnus daryanus spermatozoon was studied with light microscope（LM） and transmission electron microscope（TEM）.The lengths of different parts of spermatozoa were measured under LM,and 31 spermatozoa were measured.The results showed that the spermatozoon of Paramisgurnus daryanus could mainly be divided into three parts： head,midpiece and tail（flagellum）.There was no acrosome in the head.Head of the spermatozoon was spherical shaped under LM and TEM when it was longitudinally sectioned.Head was mainly composed of nucleus.The chromatin in the nucleus was dense.Nuclear vesicle could be seen in the nucleus.Nuclear membrane could clearly be seen outside of the nucleus.A little cytoplasm was existed in the head,adhering to the nucleus closely.There was a shallow implantation fossa at the caudal-central end of the nucleus,the depth of which was about 1/4 of the length of head,the long axis of implantation was almost paralleled with that of the nucleus,and held a centriolar complex.Midpiece was at the posterior end of the nucleus,no clear division existed between the head and midpiece,the midpiece consisted of centriolar complex and sleeve.Two sides of the sleeve were asymmetrical.The centriolar complex consisted of proximal centriole（PC） and distal centriole（DC）.The angle between PC and DC was obtuse.The tail could be divided into two parts（principal piece and end piece）,and without lateral fins on it.The principal piece of the spermatozoon tail possessed a conventional ＂9＋2＂ structure.The light microscopy measurement showed that the length of head,midpiece,tail and total length were 1.79 0.28μm,1.86±0.42μm,28.06±2.78μm and 31.65±2.82μm respectively.