中文摘要：

目的：初步探究电压门控氯通道3（ClC-3）在甲状旁腺激素（PTH）调节成骨分化过程中的作用机制。方法：采用基因转染的方法,分别用特异性siRNA调节成骨细胞MC3T3-E1中转化生长因子β1（TGF-β1）及ClC-3基因的表达水平,采用实时定量RT-PCR检测ClC-3、TGF-β1及碱性磷酸酶（ALP）、骨唾液蛋白（BSP）、骨钙素（OC）、核心结合蛋白因子2（Runx2）等成骨相关因子的基因表达情况,并用Western blot及免疫荧光方法检测CLC-3和TGF-β1蛋白的表达情况。结果：在PTH间断刺激下,成骨细胞中仅干扰TGF-β1基因表达后,ClC-3氯通道基因及蛋白表达水平增强;仅干扰ClC-3氯通道基因后,TGF-β1基因及蛋白表达水平升高。同样在PTH间断刺激下,在分别干扰ClC-3氯通道基因和TGF-β1基因后,成骨相关基因表达水平较对照组明显降低（P〈0.05）;然而共同干扰两者之后成骨相关基因表达较对照组无明显差异（P〉0.05）。结论：ClC-3氯通道通过TGF-β通路参与介导了PTH在成骨细胞中促进成骨细胞分化的作用。

英文摘要：

Objective： To investigate the mechanism of ClC-3 in the process of PTH regulating bone osteogenic differentiation.Methods： We regulated the expression of TGF-β1 and ClC-3 chloride channel in MC3T3-E1 cells with specific siRNA,and investigated the expression of Clcn3,Tgfb1 and osteogenic factors（ Alp,Bsp,Oc and Runx2） with the method of real-time RT-PCR. Then we further investigated the expression of CLC-3 chloride channel protein and TGF-β1 protein with the method of Western blot and immunofluorescence. Results： The effect of TGF-β1 gene expression on ClC-3 expression in osteoblasts under discontinuous stimulation of PTH：ClC-3 chloride channel gene and protein expression increased when TGF-β1 gene expression in osteoblasts was interrupted only. The effect of ClC-3 chloride channel gene expression on TGF-β1 expression in osteoblasts under discontinuous stimulation of PTH： TGF-β1gene and protein expression increased when ClC-3 chloride channel gene expression was interrupted only. Expression of osteogenic genes under discontinuous stimulation of PTH： Expression of osteogenic genes（ Alp,Bsp,Oc and Runx2） decreased comparing to control when ClC-3 gene and TGF-β1 gene were interrupted respectively（P〈0.05）. However,no significant difference was observed between the expression of the simultaneously interrupted genes and the control（P〉0.05）.Conclusions：ClC-3 chloride channel has been involved in the osteoinduction of PTH in the osteoblasts through the TGF-β pathway. The specific mechanism behind that requires further research.