SummaryThis study evaluated the effects of oocyte meiosis inhibitors roscovitine (ROS) and butyrolactone I (BL-I) on in vitro production of bovine embryos. Bovine oocytes were maintained in pre in vitro maturation (pre-IVM) with 25 µM ROS or 100 µM BL-I for 24 h to delay meiosis and for 24 h in in vitro maturation (IVM). Following this treatment, the nuclear maturation index was evaluated. All embryos degenerated following this procedure. In the second set of experiments, oocytes were maintained for 6 or 12 h in pre-IVM with the following three treatments: ROS (25 µM or 12.5 µM), BL-I (100 µM or 50 µM) or a combination of both drugs (6.25 µM ROS and 12.5 µM BL-I). Oocytes were cultivated for 18 or 12 h in IVM. When a meiosis-inducing agent was used during pre-IVM for 24 h, more degenerated oocytes were observed at the end of the IVM period. This effect decreased when the meiotic blocking period was reduced to 6 or 12 h. No significant differences were observed in the blastocyst production rate of oocytes in pre-IVM for 6 h with ROS, BL-I, or ROS + BL-I compared with that of the control group (P > 0.05). However, inhibition of oocytes for 12 h resulted in decreased embryo production compared with that in the controls (P < 0.05). There was no difference in the post-vitrification embryo re-expansion rate between the study groups, showing that the meiotic inhibition for 6 or 12 h did not alter the embryo cryopreservation process.

中文翻译：

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在体外成熟之前用roscovitine和丁内酯I处理会改变囊胚的产生

总结本研究评估了卵母细胞减数分裂抑制剂 roscovitine (ROS) 和丁内酯 I (BL-I)体外牛胚胎的生产。牛卵母细胞在预体外用 25 µM ROS 或 100 µM BL-I 成熟（IVM 前）24 小时以延迟减数分裂，24 小时体外成熟（IVM）。在这种处理之后，评估核成熟指数。所有胚胎在此程序后退化。在第二组实验中，卵母细胞在 IVM 前通过以下三种处理维持 6 或 12 小时：ROS（25 µM 或 12.5 µM）、BL-I（100 µM 或 50 µM）或两种药物的组合（6.25 µM ROS 和 12.5 µM BL-I）。卵母细胞在 IVM 中培养 18 或 12 小时。当在预 IVM 期间使用减数分裂诱导剂 24 小时时，在 IVM 期结束时观察到更多退化的卵母细胞。当减数分裂阻断期减少到 6 或 12 小时时，这种效果会降低。ROS、BL-I或ROS+BL-I的pre-IVM 6 h卵母细胞的囊胚生成率与对照组相比无显着差异（磷> 0.05)。然而，与对照组相比，抑制卵母细胞 12 小时导致胚胎产生减少（磷< 0.05)。研究组之间的玻璃化冷冻后胚胎再膨胀率没有差异，表明减数分裂抑制 6 或 12 小时不会改变胚胎冷冻保存过程。