猪孤雌激活4-细胞胚胎玻璃化冷冻保存效果的研究

Vitrification of Porcine Parthenogenetic 4-cell Embryos

本实验旨在研究猪孤雌激活4-细胞胚胎的冷冻保存效果。胚胎采用Cryotop法进行玻璃化冷冻保存,解冻后分析其存活率、胞内活性氧(ROS)和谷胱甘肽(GSH)水平、囊胚发育率及囊胚质量。结果表明:冷冻胚胎体外恢复2 h的存活率与新鲜胚胎无明显差异(100%vs.96.8%,P>0.05),但当其培养时间达到24 h时,存活率显著下降至88.3%(P<0.05)。另外,玻璃化冷冻导致胚胎内ROS水平显著升高(P<0.05),GSH水平显著下降(P<0.05)。与新鲜胚胎相比,冷冻胚胎获得的囊胚发育率明显降低(59.8%vs.26.4%,P<0.05),但囊胚的凋亡细胞率、内细胞团数、滋养层细胞数及总细胞数均无明显差异(P>0.05)。结果显示,玻璃化冷冻猪孤雌激活4-细胞胚胎导致其存活、氧化还原能力和囊胚发育下降,但仍能获得较高质量的囊胚。

This study was conducted to investigate the effect of vitrification on porcine parthenogenetic 4-cell embryos,using Cryotop vitrification method.After vitrification and warming,the 4-cell embryos were evaluated by their survival,intracellular reactive oxygen species（ROS） and glutathione（GSH） levels,developmental competence and blastocysts quality.The results showed that 2 h after warming,there was no difference in survival rates between vitrified and fresh embryos（100%vs.96.8%,P〈0.05）.However,the percentage of live embryos at 24 h after warming were significantly lower in the vitrified groups than in the fresh groups（100%vs.88.3%,P〈0.05）.Vitrification also significantly increased ROS,and reduced GSH levels in 4-cell embryos（P〈0.05）.The developmental rates of vitrified4-cell embryos to the blastocyst stage were significantly lower than those of fresh 4-cell embryos（59.8%vs.26.4%,P〈0.05）,but the number of apoptotic cells,inner cell mass,trophectodermcells and total cellsin blastocysts derived fromvitrified 4-cell embryos were similar to those of fresh blastocysts（P〈0.05）.The data demonstrated that vitrification causesa decrease in survival,redox potential and blastocyst development of porcine parthenogenetic 4-cell embryos,but good blastocysts can be obtained from those vitrified embryos.