兔卵巢组织玻璃化冷冻的实验研究

Experimental study on vitrification freezing for rabbit ovarian tissue

目的:探讨玻璃化冷冻法保存兔卵巢组织的效果。方法:随机将25只新西兰雌兔分为对照组(5只)、慢速冷冻组(10只)和玻璃化冷冻组(10只),比较各组冻融前后卵巢组织学、超微结构、卵泡凋亡(原位末端标记法,TUNEL)和子宫系膜内移植后卵巢功能的恢复情况。结果:新鲜组织、慢速冷冻复苏组织和玻璃化冷冻复苏组织中正常形态卵泡比例分别为87.36%、81.96%和82.72%,两冷冻组正常卵泡比例均低于对照组,差异有统计学意义?P(0.05),但玻璃化冷冻组与慢速冷冻组差异无统计学意义(P>0.05)。3组间卵泡凋亡比率分别为21.4%、13.5%和17.1%,差异无统计学意义(P>0.05);3组移植后兔动情周期出现率均为100%,动情周期出现天数差异无统计学意义?P>0.05);移植存活的卵巢组织内可见各级形态正常的卵泡发育。结论:玻璃化冷冻可有效保存卵巢组织的结构和功能,是一种简单、可行的兔卵巢组织冷冻保存法。

Objective ：To explore the efficiency of vitrification freezing for rabbit ovarian tissue. Methods：Twenty five New Zealand White female rabbits were divided into three groups randomly, control group （n = 5 ） ;conventional slow freezing group （n = 10 ） ;vitrification group（ n = 10）. Morphology, ultrastructures and DNA fragmentation were compared between fresh and the post thawing tissue. Some mesometrium,estrus cycle was observed integral follicles rates in slow freezing of ovarian tissues were autologously transplanted into after ovarian autografting. Results： The morphological and vitrification groups were lower than those of the control group（ P 〈 0.05 ） ; but no significant differences were observed between the two types of freezing protocols （ P 〉 0. 05 ） ; the percentages of TUNEL-positive oocytes were 21. 4%, 13.5%and 17. 1% for control group,slow freezing group and vitrification freezing group,respectively ,there was no statistical significance among 3 groups（ P 〉 0.05 ） ,but was slightly lower for the frozen fragments for both protocols with respect to the the percentage control group ; the initiation rate of estrus were all 100%, there was no significant difference in the initiation days of estrus among 3 groups（P 〉 0.05 ）. Conclusion：The vitrification freezing may be used as an efficient, simple and feasible cryopreservation method for ovarial histologic and physiological function.