中文摘要：

目的 研究高血糖对排卵前小鼠卵母细胞发育及颗粒细胞凋亡的影响。方法 出生后20dICR雌鼠，建立急性高血糖模型；取高血糖模型雌鼠和正常雌鼠超排卵，分别于hCG注射后的0、2．6和10h取卵巢组织，石蜡切片，TUNEL检测凋亡，免疫组织化学ABC法检测连接蛋白connexin-43的表达，相同时间点取生发泡期（GV期）卵母细胞统计生发泡破裂（GVBD）和第一极体（FB1）的发生率。结果 1．高血糖组卵巢湿重与小鼠体重的比值与排卵数目均低于正常组（P〈0．01）；2．免疫组织化学显示，hCG注射后6h、10h颗粒细胞表达connexin-43在高血糖组明显低于正常组（P〈0．05）；3．高血糖组卵泡颗粒细胞的凋亡率明显高于正常组，hCG注射后6h、10h差异最显著（P〈0．05）；4．高血糖组卵母细胞GVBD发生率低于正常组，于注射后2h差异最显著（P〈0．01）。结论 高血糖环境下卵母细胞发育延迟，颗粒细胞的凋亡率增高。这种发育延迟与颗粒细胞间connexin-43低表达呈正相关。

英文摘要：

Objective To study the effects of hyperglycemia on preovulatory oocyte maturation, development and granulosa cell apoptosis. Methods Female mice （20-day-old） were used to generate diabetic models. Diabetic group and age- matched controls received superovulation with 10 IU of PMSG and hCG. At the appropriate time points following hCG injection （ t = 0h, 2h, 6h and 10h）, the ovaries were removed and then paraffin embedded. The expression of connexin-43 was detected by immunohistochemistry. The apoptosis of granulosa ceils observed was by TUNEL staining. Results 1. Both the ovaries＇ wet weight ratio to the body weight and the number of eggs ovulated were lower in the hyperglycemia group than those in the control group. 2. The expression of connexin-43 detected by immunohistochemistry in the follicles in the hyperglycemia group was greater than that in the control group at the 6th and 10th hours after hCG injection. 3. There were remarkably more TUNEL-positive follicles in the diabetic follicles than in the non-diabetic group. And the difference was the most notable at the 6th and 10th hours after hCG injection. 4. Lower percentage of oocytes reached GVBD in the diabetic than that in the controls at the 6th and 10th hours. Conclusion Delayed maturation was observed in the oocytes from those hyperglycemia mice. Hyperglycemia increased granulosa cell apoptosis. The early developmental delay of oocytes may correlate to the low expression of connexin-43.