绵羊体外成熟卵母细胞的电激活及其在体外孤雌发育的研究

ELECTRICAL ACTIVATION OF IN VITRO MATURED (IVM) OVINE OOCYTES AND THEIR PARTHENOGENETIC DEVELOPMENT IN VITRO *

首先对绵羊卵母细胞收集及其体外成熟（ＩＶＭ）条件进行了摸索，然后对影响电刺激激活ＩＶＭ卵母细胞的因素进行了研究，观察激活后卵母细胞在体外的发育能力。结果表明，剥离法比注射器吸卵法所获得的卵母细胞成熟率高，激活更加正常。剥离法收集的卵母细胞体外成熟培养２７小时后，以含０１ｍｍｏｌ／ＬＣａＣｌ２、０１ｍｍｏｌ／ＬＭｇＳＯ４和１０ｍｍｏｌ／Ｌ组氨酸的０２８ｍｏｌ／Ｌ肌醇（ｉｎｏｓｉｔｏｌ）作基础电击液，施以２次脉冲（间隔２２分钟）可获得最佳的激活效果。激活后的卵母细胞，在体外培养后进一步观察到，先在ＣＺＢ中与输卵管上皮细胞（ＳＯＥＣ）共同培养４８小时，再转移至Ｍ１９９＋１０％胎牛血清及ＳＯＥＣ共同培养，卵母细胞分裂率（７８３％）及桑椹胚和囊胚发育率（３０％）明显提高。

In the present paper, the methods of collecting ovine oocytes and the optimal conditions for in vitro maturation of ovine oocytes were reported. The factors affecting electrical activation of IVM oocytes and the parthenogenetic development in vitro after activation were studied. The results showed that the maturation rate of ovine oocytes collected by dissection was higher than by aspiration, and the activation of these oocytes after in vitro maturation was more regular. The optimal activation rate was obtained from oocytes collected by dissection after maturation in vitro for 27 h under 2 electrical pulses delivered at an interval of 22 min in 0 28 mol/L inositol solution containing 0 1 mmol/L CaCl 2, 0 1 mmol/L MgSO 4 and 10 mmol/L histidine. Coculture the activated oocytes in M199+10% FBS+SOEC (sheep oviduct epthelial cells) after coculture in CZB+SOEC for 48 h increased the cleavage rate and the rate of developmentto morula and blastula in vitro to 78 3% and 30% respctively.