拟目乌贼精子发生和精子的超微结构  

Ultrastructure of Spermatogenesis and Mature Spermatozoa in Sepia lycidas

作　　者：罗江[1] 蒋霞敏[1] 唐锋[1] 彭瑞冰[1] 

机构地区：[1]宁波大学海洋学院,宁波315211

出　　处：《动物学杂志》2014年第1期71-82,共12页Chinese Journal of Zoology

基　　金：国家农业成果转化项目(No.2009GB2C220415);宁波市重点科技项目(No.2011C11002)

摘　　要：应用扫描电镜和透射电镜观察了拟目乌贼(Sepia lycidas)精子的发生过程和超微结构。结果表明,精子发生经历了精原细胞、初级精母细胞、次级精母细胞、精细胞和成熟精子5个阶段,其中精细胞可以分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ5个时期,精细胞Ⅱ期又可分为前期和后期。细胞核经历了一个横向收缩、纵向拉长的过程,由圆形或椭圆形,变为不规则的纺锤形、稍弯曲的长柱形;核内染色质由絮状,变为絮块状、致密颗粒状、细纤维状、粗纤维状和片层状,直至高电子密度均质状;顶体由圆形,变为头盔形、圆锥形、倒"U"字形,直至子弹头形;线粒体由空泡状经过融合和迁移,变为内嵴丰富的椭球形,形成不完全包围鞭毛的线粒体距。成熟精子全长101.28μm,由头部和尾部组成,头部呈长辣椒状,长7.73μm,宽1.51μm,由顶体和细胞核组成;尾部细长,为93.18μm,为典型的"9+2"结构,由中段、主段和末段三部分组成。The ultrastructures of spermatogenesis and mature spermatozoa in Sepia lycidas were determined by scanning electron microscopy and transmission electron microscopy. The results show that there are five developmental stages of spermatogenesis： spermatogonium, primary spermatocyte, secondary spermatocyte, spermatid, and mature spermatozoon. The spermatid undergoes five phases （Ⅰ through Ⅴ） for differentiation, and the phase Ⅱ can be further divided into early and late periods. During spermameiogenesis, the nucleus undergoes a process of lateral contraction and longitudinal elongation, making it convert from a round or oval shape to an irregular spindle-like shape, and finally to a slightly curved long cylinder shape; the size of the nucleus reduces from 6.27 μm × 5.84 μm to 5.75 μm × 1.53 μm. The chromatin in the nucleus forms flocculent blocks, dense granules, fine fibers, crude fibers, and lamellae, and condenses into a region with a high electron density. The morphology of acrosome is also changed, from a round shape with a diameter of 1.02 μm, to helmet-like, conical, backward ＂U＂-like, and finally to bullet-like with a length of 1.71 μm and a maximum width of 0.91 μm. The vacuole-shaped mitochondria experience migration and fusion, and they exhibit an oval shape with abundant cristae, and form a mitochondrial spur that incompletely surround the flagellum in the middle piece. The mature spermatozoa are 101.28 μm long, and consist of a head and a tail. The head shows a long pepper shape, approximately 7.73 μm in length and 1.15 μm in width, and it consists of an acrosome and a nucleus. The arosome resembles a bullet with a length of 1.71 μm and a width of 0.91 μm, and the nucleus is slightly curved and cylindrical, and is approximately 5.75 μm long and 1.53 μm wide. The 93.18 μm long tail is slender with a typical ＂9＋2＂ structure, and it consists of middle, principal, and end pieces.

关 键 词：拟目乌贼 精子发生 精子 超微结构 

分 类 号：Q954.4[生物学—动物学]