Chen C, Sathananthan A H
Arch Androl. 1986;16(3):183-97. doi: 10.3109/01485018608986940.
Penetration of human sperm through the vestments of human oocytes during the first 3 h after insemination was investigated to determine the time taken for sperm capacitation, which precedes the acrosome reaction and fertilization. Twelve oocytes from women who became pregnant by IVF, recovered at laparoscopy after appropriate stimulation, were examined by electron microscopy. Follicular development was controlled by administration of clomiphene citrate, hMG, and hCG. Oocytes were cultured in Whittingham's T6 medium for 7-14 h before insemination and were fixed 1-3 h after insemination with preincubated sperm obtained from fertile men. All oocytes had matured and eight were normally fertilized 2-3 h after insemination. The acrosome reaction had already begun 1 h after insemination when 10-30% of sperm had reacted. Sperm-oocyte membrane fusion occurred 2 h after insemination, and sperm decondensation and pronuclear formation were in progress 3 h after insemination. Variable numbers of sperm (30-60%) had reacted acrosomes after 2-3 h of insemination. Many sperm penetrating the cumulus were intact or had partially reacted acrosomes. Intact, partially and fully reacted sperm were found at the surface of the zona. Intact sperm were bound to the zona by their plasma membranes. Sperm penetrating the zona had reacting or reacted acrosomes exposing their inner acrosome membranes. Those approaching the perivitelline space had a persistent equatorial vestige of the acrosome with intact plasma membrane. The acrosome reaction involved multiple fusions of the sperm plasma and outer acrosome membranes, resulting in vesiculation. This study shows that human sperm could complete capacitation and initiate the acrosome reaction within 1 h of insemination in vitro.
为了确定精子获能所需的时间（获能先于顶体反应和受精），研究了授精后最初3小时内人类精子穿透人类卵母细胞被膜的情况。通过电子显微镜检查了12个经适当刺激后在腹腔镜检查时回收的、通过体外受精怀孕女性的卵母细胞。卵泡发育通过服用枸橼酸氯米芬、人绝经期促性腺激素和人绒毛膜促性腺激素来控制。卵母细胞在授精前于惠廷厄姆T6培养基中培养7 - 14小时，并在授精后1 - 3小时用从有生育能力男性获得的预孵育精子固定。所有卵母细胞均已成熟，8个在授精后2 - 3小时正常受精。授精1小时后顶体反应已经开始，此时10 - 30%的精子发生了反应。精子 - 卵母细胞膜融合在授精后2小时发生，精子解聚和原核形成在授精后3小时进行。授精2 - 3小时后，不同数量（30 - 60%）的精子发生了顶体反应。许多穿透卵丘的精子完整或顶体部分反应。在透明带表面发现了完整、部分和完全反应的精子。完整的精子通过其质膜与透明带结合。穿透透明带的精子顶体正在反应或已经反应，露出其顶体内膜。那些接近卵周隙的精子顶体赤道部有残留且质膜完整。顶体反应涉及精子质膜和顶体外膜的多次融合，导致形成小泡。本研究表明，人类精子在体外授精1小时内可完成获能并启动顶体反应。
