胚鼠宫内缺血缺氧脑损伤中Wnt信号通路关键分子的表达变化

Changes of the Wnt Signalling Key Effectors in Brain of Rat Embryo Suffering from Intrauterine Hypoxia-ischemia Brain Damage

目的探讨Wnt信号通路与胚鼠宫内缺血缺氧脑损伤的关系。方法将孕15-17d的SD大鼠随机分为实验组和对照组。实验组钳夹双侧子宫动脉30min建立宫内缺血缺氧模型,分别在缺血再灌注24、48、72h后留取胚脑标本。对照组不钳夹子宫动脉,与实验组的对应时间点留取标本。采用尼氏染色和Caspase-3免疫组化检测两组神经元的凋亡情况。Western Blotting检测Wnt信号通路中关键信号分子β-catenin和GSK-3β的表达变化。结果实验组再灌注后不同时间点尼氏小体嗜染性降低,部分溶解。Caspase-3阳性细胞数较对照组升高,其中对照组为12.71±1.42（24h）、11.45±1.50（48h）、14.10±1.29（72h）,实验组为26.29±1.64（24h）、32.38±1.05（48h）、39.20±1.88（72h）,差异均具有统计学意义（P〈0.05）。Western Blotting显示β-catenin蛋白表达在实验组与对照组之间差异无统计学意义（P〉0.05）,而GSK-3β实验组的相对表达量较对照组显著增高,其中对照组为1.75±1.07（24h）、1.34±1.03（48h）、1.48±1.10（72h）,实验组为3.25±1.34（24h）、2.99±1.26（48h）、3.10±1.35（72h）,差异均具有统计学意义（P〈0.05）。结论Wnt信号通路在胚鼠宫内缺血缺氧脑损伤中可能发挥重要作用。

Objective To investigate the relationship between Wnt pathway and intrauterine hypoxia-ischemia brain damage.Methods The gestational rats（15-17days）were randomLy divided into sham operation group and transient intrauterine ischemia group.For transient intrauterine ischemia group,the gestational rats＇ bilateral uterine arteries were clamped for 30 min,followed by reperfusion.For sham operation,animals were subjected to the same surgical procedures,except that bilateral uterine arteries were not clamped.Samples were collected at 24,48,and 72 h after reperfusion.The whole brain tissues were dissected for Nissl stain and Caspase-3 immumohistochemical.The expressions of GSK-3β and β-catenin protein in the two groups were analyzed with Western Blotting.Results The Nissl body of the transient intrauterine ischemia group decreased and the masculine cell of Caspase-3 was significantly higher than sham operation group at each time point（P〈0.05）.The sham operation group is 12.71±1.42（24 h）,11.45±1.50（48 h）,14.10±1.29（72 h）and the transient intrauterine ischemia group is 26.29±1.64（24 h）,32.38±1.05（48 h）,39.20±1.88（72 h）.β-catenin expression between the two groups was no statistically significant difference.However,expression of GSK-3β in transient intrauterine ischemia group increased（P〈0.05）.The sham operation group is 1.75±1.07（24 h）,1.34±1.03（48 h）,1.48±1.10（72 h）and the transient intrauterine ischemia group is 3.25±1.34（24 h）,2.99±1.26（48 h）,3.10±1.35（72 h）.Conclusion Wnt pathway may play an important part in intrarterine hypoxia-ischemia brain damage.