促黄体素对牛卵母细胞体外核成熟的影响

为了研究促黄体素(luteinizing hormone,LH)在牛卵母细胞成熟培养体系中的时间依从性,试验通过向牛卵母细胞体外成熟培养的不同时间段添加LH来观察其核成熟的情况。首先用无LH的基础成熟液I和添加LH的成熟液Ⅱ分别培养,在成熟的不同时间点(3、6、9h)用醋酸地衣红染色观察各自的生发泡破裂率。然后在体外成熟培养的不同时间段(0～3、0～6、0～9、0～24h)添加LH,24h后统计各自的第一极体率。结果表明,添加LH组在6h的生发泡破裂率显著低于对照1组(P0.05),24h添加LH组的第一极体率显著高于对照2组(P0.05)。因此,添加LH能延迟牛卵母细胞的核成熟,成熟培养中24h全程添加LH较不添加组能显著提高核成熟率。

Effect of Different Durations Treated by Luteinizing Hormone on Maturation in Vitro of Bovine Oocytes

In this study, it was aimed to investigate the effect of different treatment durations of luteinizing hormone (LH) on maturation in vitro of bovine oocytes. The experiments were designed as following：first,the bovine cumulus oocytes complexes(COCs) were matured in vitro in medium with or without LH, the appropriate GVBD rate about it was recorded and analyzed to determine the time course of their maturation in vitro. Second,the bovine COCs were in vitro matured in medium with LH during different durations respectively (0 to 3 h,0 to 6 h,0 to 9 h and 0 to 24 h). After 24 h for in vitro maturation, their percentage of polar bodyⅠ(pbⅠ) was also analyzed. The GVBD rate in the group treated with LH for 6 h(30.19%±5.22％) was significantly lower than the control 1 group (48.42%±5.92%) (P＜0.05). Meanwhile, the percentage of polar bodyⅠ(pbⅠ) in group 4 treated by LH (81.05%±2.70％) was significantly higher than that of the control 2 group (65.89%±3.34％)(P＜0.05). Thus, it might be concluded that LH may improve the nuclear maturation of bovine oocytes while they are matured in vitro within 24 h.