Du Y, Pribenszky C S, Molnár M, Zhang X, Yang H, Kuwayama M, Pedersen A M, Villemoes K, Bolund L, Vajta G
Population Genetics and Embryology, Faculty of Agricultural Sciences, Institute of Genetics and Biotechnology, University of Aarhus, DK-800 Aarhus, Denmark.
Reproduction. 2008 Jan;135(1):13-7. doi: 10.1530/REP-07-0362.
The purpose of the present study was to improve cryotolerance using high hydrostatic pressure (HHP) pretreatment of porcine in vitro matured (IVM) oocytes, to facilitate their further developmental competence after parthenogenetic activation. A total of 1668 porcine IVM oocytes were used in our present study. The pressure tolerance and optimal duration of recovery after HHP treatment were determined. Oocytes were treated with either 20 or 40 MPa (200 and 400 times greater than atmospheric pressure) for 60 min, with an interval of 10, 70, and 130 min between pressure treatment and subsequent vitrification under each pressure parameter. Oocytes from all vitrification groups had much lower developmental competence than fresh oocytes (P<0.01) measured as cleavage and blastocyst rates. However, significantly higher blastocyst rates (P<0.01) were obtained in the groups of 20 MPa pressure, with either 70 (11.4+/-2.4%) or 130 (13.1+/-3.2%) min recovery, when compared with the vitrification control group without HHP treatment where no blastocysts were obtained. The influence of temperature at HHP treatment on further embryo development was also investigated. Treatments of 20 MPa with 70 min recovery were performed at 37 degrees C or 25 degrees C. Oocytes pressurized at 37 degrees C had a significantly higher blastocyst (14.1+/-1.4%) rate than those treated at 25 degrees C (5.3+/-1.1%; P<0.01). Our results demonstrate that HHP pretreatment could considerably improve the developmental competence of vitrified pig in vitro matured (IVM) oocytes. The HHP pretreatment will be tested as a means to improve survival and developmental competence at different developmental stages in different species including humans.
本研究的目的是通过对猪体外成熟（IVM）卵母细胞进行高静水压（HHP）预处理来提高其耐冻性，以促进孤雌激活后它们进一步的发育能力。本研究共使用了1668枚猪IVM卵母细胞。确定了HHP处理后的耐压性和最佳恢复持续时间。卵母细胞分别用20或40兆帕（比大气压高200和400倍）处理60分钟，在每个压力参数下，压力处理与随后玻璃化之间的间隔时间分别为10、70和130分钟。以卵裂率和囊胚率衡量，所有玻璃化组的卵母细胞发育能力均远低于新鲜卵母细胞（P<0.01）。然而，与未进行HHP处理且未获得囊胚的玻璃化对照组相比，20兆帕压力组、恢复70（11.4±2.4%）或130（13.1±—3.2%）分钟时，获得了显著更高的囊胚率（P<\0.01）。还研究了HHP处理时的温度对胚胎进一步发育的影响。在37℃或25℃下进行20兆帕、恢复70分钟的处理。在37℃下加压的卵母细胞囊胚率（14.1±1.4%）显著高于在25℃下处理的卵母细胞（5.3±1.1%；P<0.01）。我们的结果表明，HHP预处理可显著提高玻璃化猪体外成熟（IVM）卵母细胞的发育能力。HHP预处理将作为一种提高包括人类在内的不同物种不同发育阶段的存活率和发育能力的方法进行测试。
