中文摘要：

目的：探讨经典Wnt信号通路在大鼠胫骨牵张成骨中不同时期的表达变化。方法：建立大鼠胫骨牵张成骨模型,在牵张结束当日与固定第4周获取标本,用实时荧光定量PCR及免疫组化技术检测Wnt3A和β-catenin在牵张骨痂中的时空表达。结果：在牵张结束时经典Wnt信号通路的两个关键蛋白分子Wnt3A及β-catenin在牵张骨痂成骨细胞中有强阳性表达,固定4周后表达水平显著减弱（P〈0.05）。结论：牵张力作用可激活经典Wnt信号通路,从而参与牵张成骨的分子调控过程。

英文摘要：

Objective：To observe the expression of canoical Wnt signaling proteins at various times in distracted rat tibia.Methods：We established rat tibia distraction osteogenesis model.The animals were sacrificed at the end of DO and 28days post-DO.RT-PCR and immune-staining were used to analyze spatial and temporal expression of Wnt3A and β-catenin in the distracted gap.Results：The expression of Wnt3A and β-catenin were significantly up-regulated,especially in osteoblasts,at the end of distraction and it is down-regulated at 28 days post-DO（P〈0.05）.Conclusion：Bio-mechanical stimulation could activate canonical Wnt signal pathway and participate in the molecular regulation process.