6-二甲基氨基嘌呤对体外成熟山羊卵母细胞孤雌激活及发育的影响

Effect of 6-Dimethylaminopurine on Activation and Development of In Vitro Matured Goat Oocytes Following Parthengogentic Stimulation

体外成熟的山羊卵泡卵母细胞用7%的乙醇和5μmol/L的离子霉素刺激处理后,分别置于含2 mmol/L 6-二甲基氨基嘌呤(6-DMAP)和不含6-DMAP的培养液中培养4 h,研究6-DMAP对体外成熟山羊卵泡卵母细胞孤雌激活率、原核形成以及孤雌胚体外发育潜能的影响。结果表明:6-DMAP能显著提高山羊卵母细胞的激活率,乙醇+6-DMAP和离子霉素+6-DMAP处理卵母细胞激活率分别为75.6%和71.1%,均显著高于单独使用乙醇(54.3%)和离子霉素(56.8%)处理;显著抑制卵母细胞第二极体的排出,乙醇+6-DMAP和离子霉素+6-DMAP处理仅含1个极体的孤雌胚分别为90.3%和96.3%,显著高于单独使用乙醇(26.3%)离子霉素(33.3%)处理。孤雌胚体外培养7 d,乙醇+6-DMAP和离子霉素+6-DMAP处理4-细胞发育率为45.6%和47.9%,8-细胞孤雌胚发育率为25.0%和29.6%,桑/囊胚形成率为7.4%和9.9%,均显著高于单独使用乙醇和离子霉素处理(P<0.05)。

The present study was conducted to investigate the effect of 6-DMAP on parthenogenetic activation rate,pronuclear formation and in vitro parthenote development of in vitro matured goat oocytes.The activation rate of oocytes treated by ethanol or ionomycin combination with 6-DMAP was 75.6% and 71.1%,and higher than that of ethanol or ionomycin treated alone（54.3%,56.8 P〈0.05）.The percentage of activated oocytes with pronuclearfter ethanol or ionomycin combination with 6-DMAP was 90.3% and 96.3% higher than ethanol or ionomycin stimulation alone（26.3%,33.3% P〈0.05）.Incubation with 6-DMAP following ethanol or ionomycin activation reduced the incidence of second polar body extrusion and significantly enhanced the proportion of oocytes with one polar body（Pb1） compared with ethanol or ionomycin activation alone.After 7 days of culture in vitro,the oocytes treated by ethanol or ionomycin in combination with 6-DMAP displayed significantly increased rates of 4-cell（45.6%,47.9%）,8-cell（25.0%,29.6%） and blastocyst stages（7.4%,9.9%） compared with oocytes treated by ethanol or ionomycin alone（P〈0.05）.In conclusion,the major results of the present study clearly indicate that combined treatment of ethanol or ionomycin with 6-DMAP significantly increases parthenogenetic activation rate,pronuclear formation and in vitro parthenote development of in vitro matured goat oocytes.