Yan Chang-Liang, Yang Qi-En, Zhou Guang-Bin, Hou Yun-Peng, Zhao Xue-Ming, Fan Zhi-Qiang, Liu Man-Qing, Liu Lin, Zhu Shi-En
College of Animal Science and Technology, China Agricultural University, Beijing, PR China.
Acta Vet Hung. 2008 Jun;56(2):245-53. doi: 10.1556/AVet.56.2008.2.12.
The present study was designed to investigate the cryotolerance of in vitro fertilised (IVF) mouse embryos at various preimplantation developmental stages. IVF mouse embryos were vitrified by the open-pulled straw (OPS) method. After warming, embryos were morphologically evaluated and assessed by their development to blastocysts, hatched blastocysts or term. The results showed that a high proportion (93.3-100.0%) of vitrified embryos at all developmental stages were morphologically normal after recovery. The developmental rate of vitrified 1-cell embryos to blastocyst (40.0%) or hatched blastocyst (32.7%) or term (9.3%) was significantly lower than that from other stages (P < 0.05). Vitrified embryos from 2-cell to early blastocyst stage showed similar blastocyst (71.8-89.5%) and hatched blastocyst rates (61.1-69.6%) and could develop to term without a significant loss of survival compared with those of fresh embryos (P > 0.05). Vitrified 2-cell embryos showed the highest survival rate in vivo (50.6%, 88/174), compared with that from other stages (9.3-30.5%, P < 0.05). The data demonstrate that the OPS method is suitable for the cryopreservation of IVF mouse embryos from 2-cell stage to early blastocyst stage without a significant loss of survival. Embryos at the 2-cell stage had the best tolerance for cryopreservation in the present study.
本研究旨在调查体外受精（IVF）小鼠胚胎在不同着床前发育阶段的耐冻性。IVF小鼠胚胎通过开放式拉长细管（OPS）法进行玻璃化冷冻。解冻后，对胚胎进行形态学评估，并根据其发育至囊胚、孵化囊胚或足月的情况进行评估。结果显示，所有发育阶段的玻璃化冷冻胚胎解冻后形态正常的比例都很高（93.3 - 100.0%）。玻璃化冷冻的1细胞胚胎发育至囊胚（40.0%）、孵化囊胚（32.7%）或足月（9.3%）的发育率显著低于其他阶段（P < 0.05）。从2细胞到早期囊胚阶段的玻璃化冷冻胚胎显示出相似的囊胚率（71.8 - 89.5%）和孵化囊胚率（61.1 - 69.6%），与新鲜胚胎相比，能够发育至足月且存活率无显著损失（P > 0.05）。玻璃化冷冻的2细胞胚胎在体内显示出最高的存活率（50.6%，88/174），与其他阶段相比（9.3 - 30.5%，P < 0.05）。数据表明，OPS法适用于2细胞阶段至早期囊胚阶段的IVF小鼠胚胎的冷冻保存，且存活率无显著损失。在本研究中，2细胞阶段的胚胎对冷冻保存具有最佳耐受性。
