大菱鲆成熟精子、卵子及精子入卵早期过程的电镜观察

Electronic microscopic observations on the sperm, egg and initial stages of fertilization of Scophthalmus maximus

中文关键词: 大菱鲆  卵子  精子  精子入卵  扫描电镜

英文关键词: Scophthalmus maximus  Egg  Spermatozoon  Sperm penetration  SEM

中文摘要:

      通过人工授精和电镜技术，观察和描述了大菱鲆Scophthalmus maximus成熟精卵的形态、精子入卵的早期过程及精子入卵过程发生的一系列形态结构变化。大菱鲆卵子表面均匀地布满纵横交错的网纹，并整齐地分布许多微小孔，在动物极有一个受精孔。大菱鲆精子为无顶体类精子，由头部、中片和尾部三部分组成，中片有9～14个圆形线粒体。大菱鲆精子入卵速度非常快，授精后0～5 s已经有精子通过受精孔（Micropyle）进入卵子。精子入卵过程还伴随着其他一些结构的变化，如精孔管管壁边缘由锯齿状变为平滑的环状等。

英文摘要:

      The morphology of mature egg and sperm of Scophthalmus maximus, and initial stages of sperm penetration were observed under scanning electron microscopy(SEM). The cortex had been observed with TEM. The micropyle consists of a depressed vestibule and a canal. A lot of small holes were found on the vestibule and the outer chorionic surface. Spermatozoon of S. maximus consists of an acrosome-less head, a short midpiece containing 9-14 mitochondria, and a long tail. The speed of sperm penetration was very fast. During 0-5 seconds post insemination, sperm entered the eggs. During the sperm penetration, there were some structure changes, for example, the sperm became bigger, the mitochondria disappeared, and the jagged circle in the inner wall of the micropyle tunnel turned into slippery circle.