小鼠附睾头精子获得与卵子质膜融合能力的物质基础研究

MOUSE SPERMATOZOA IN CAPUT EPIDIDYMES OWN THE SUBSTANTIAL BASIS FOR SPERM EGG MEMBRANE FUSION

随着精子在附睾中的转运 ,它们与卵子质膜的融合能力逐渐增加。已经证明附睾体和附睾尾的精子均具有相当高的膜融合能力 ,而附睾头中的精子则很少能与卵子质膜融合 ,这是否说明附睾头中的精子不具备与去透明带卵子融合的物质条件呢 ?利用附睾结扎滞留并延长体外获能时间 ,可使附睾头远端精子的融合能力明显地提高 ;在精子培养液中加入ATP ,并延长精卵共培养时间 ,也可使一少部分附睾头近端的精子获得与卵子质膜融合的能力。这表明附睾头中的精子已具有与卵子质膜融合的物质条件 ,附睾成熟的作用则是使附睾中精子的膜融合潜力得以充分发挥 ;此外 。

Mammalian spermatozoa go through the process of epididymal maturation to develop their capacity for fertilization. Is the sperm epididymal maturation indispensable for preparing the substantial basis for fusing with the plasma membrane of the eggs? As the spermatozoa in the corpus and cauda epididymis were proven to have obtained the capacity of fusion with the zona free eggs, here, we focused on the spermatozoa from the caput epididymis. Through prolonged detaining in the epididymes by ligation and elegation of capacitation time, the fusion ability of the spermatozoa in distal caput epididymes were significantly improved. In addition,the fusion ability of spermatozoa from ATP addition to the culture medium and long culture time were demonstrated to improve the proximal caput epididymes. These results indicate that the mouse spermatozoa in caput epididymes have obtained the substantial basis for sperm egg membrane fusion; while the epididymal transfer was not responsible for the development of membrane fusion ability. It is also suggested that improving the motility of spermatozoa from caput epididymis is the way to improve their fusibility with egg plasma membrane.