圆头精子的冷冻保存

目的:探讨圆头精子的冷冻保存效果及其精子功能改变。方法:6例圆头精子症患者各提供1-3份精液标本,应用不含卵黄冷冻保护剂和二步降温方法冷冻保存圆头精子症标本,检测冷冻精子活动率、头-尾膜完整率、存活时间和顶体蛋白酶活性。结果:圆头精子标本冷冻保存后,精子活动率显著减少,膜完整率显著下降,头膜损伤-尾膜完整的精子率显著升高(n=13,P＜0.01)。体外存活时间缩短。精子冷冻前后无顶体蛋白酶活性。不含卵黄冷冻保护剂与含卵黄冷冻保护剂,以及两步冷冻与多步冷冻的效果比较未见显著差异(n=7,P＞0.05)。结论:圆头精子可经历冷冻保存后存活,但冷冻复苏率低。冷冻-解冻过程显著降低精子功能。不含卵黄冷冻保护剂和两步降温可应用于冷冻保存圆头精子症标本。

Cryopreservation of round-headed human sperm

AIM: To investigate the cryopreservation of round-headed (globozoospermia) human sperm. METHODS: Round-headed sperm samples ( n= 13) were obtained from 6 infertile men. Yolk-free cryoprotective medium and the two-step freezing were used in cryopreserving samples. Frozen sperm functions were examined by using motility evaluation, sperm head-tail membrane integrity test, and survival time test. RESULTS: The results showed that sperm motility, membrane integrity rates, survival time in vitro significantly lowered after thawing ( n= 13, P< 0 01). No acrosomal proteinase activity was detected in both fresh and frozen sperm groups ( n= 5). There were no significant difference in post-thawing motility between yolk-free cryoprotective medium and yolk medium, and between two-step freezing and multiple-step freezing ( n= 7, P> 0 05). CONCLUSION: Human round-headed sperm could undergo the freezing-thawing process. However, cryo-survival rates were low. Frozen sperm functions were significantly decreased. Yolk-free cryoprotective medium and two-step freezing could be used in the cryopreservation of round-headed sperm. [