关键词: 牛精子, 获能, 超微结构

Abstract: Bovine frozen semen were thawed and capacitated in vitro by heparin and caffeine for 1h. The ultrastructrual changes of sperm after capacitation were observed under transmission electron microscope. The results were as follows (1) Both of the bovine sperm acrosome inner membrane and outer membrane were double layered; (2) There were various patterns of acrosome viscularization after sperm capacitation, such as fusion of plasma membrane and acrosome outer membrane, self fusion of the double layered acrosome outer membrane, invagination of acrosome outer membrane or extrudation and fusion of double layered acrosome inner membrane; furthermore several vesicularization patterns could be seen in the same sperm acrosome reaction; (3) After capacitation, the post part of the sperm head nucleous membrane without acrosome covered expanded and fused with expanded plasma membrane; (4) After capactiation, the tail membrane expanded, and the mainpiece of the plasma membrane was much more expanded than that of the midpiece part, which may be related with hyperactivation.

Key words: Bovine sperm, Capacitation, Ultrastructure