中文摘要：

目的 ：探讨狼疮鼠（MRL/lpr）骨BMP/Smads信号通路表达情况。方法 ：分离小鼠股骨制备组织切片,常规苏木素-伊红（HE）染色,观察骨质情况;免疫组化观察骨组织中骨形态发生蛋白-2（bone morphogenetic protein-2,BMP-2）表达;密度梯度离心法和贴壁筛选法分离培养骨髓间充质干细胞（bone marrow masenchymal stem cells,BMMSCs）,细胞爬片后免疫荧光法观察BMP-2、p-Smad1/5/8蛋白表达情况;BMP-2诱导BMMSCs向成骨细胞分化,RT-PCR法检测BMMSCs ALP、Runx2基因m RNA水平,ALP染色鉴定早期成骨情况。结果：狼疮鼠骨皮质较正常鼠减少,皮质骨占骨体积比例较正常鼠减低（P〈0.01）;狼疮鼠股骨BMP-2表达与正常鼠无明显差别（P〉0.05）;细胞免疫荧光显示狼疮鼠BMMSCs BMP-2、p-Smad1/5/8表达减弱（P〈0.05）;狼疮鼠BMMSCs BMP-2刺激7 d后ALP活性较正常鼠减低,BMP-2刺激3 d后ALP m RNA水平较正常鼠减弱（P〈0.01）,Runx2 m RNA水平较正常鼠无明显差别（P〉0.05）。结论 ：狼疮鼠骨BMP/Smads信号通路处于抑制状态。

英文摘要：

Objective：To investigate the status of BMP/Smads signaling pathway on the bone of lupus mice（MRL/lpr）. Methods： The femurs of the mice were isolated, and the bone structure was detected by hematoxylin-eosn （HE）staining. The protein expression levels of bone morphogenetic protein-2（BMP-2）were measured by immunohistochemistry. Bone marrow mesenchymal stem cells （BMMSCs）were isolated by the density gradient centrifugation and the adherence screening methods. After BMMSCs growing on coverslips,the protein of BMP-2 and PSmadl/5/8 was valued by immumofluorescence method. The mRNA expressions of ALP, Runx2 of BMMSCs were measured by Real-time PCR,and the Alkaline phosphatase（ALP）staining was performed for measuring the early osteogenic differentiation induced by BMP-2. Results： Compared with the controlled mice,the cortex of MRL/lpr mice were reduced （P 〈 0.01）. There was no difference in the BMP-2 expression on the bone of the two groups by immunohistochemistry detection （P 〉 0.05）. The expressions of BMP-2 and PSmadl/5/8 in BMMSCs of lupus mice were lower than those of the control group （P 〈 0.05）. After 7 days of BMP-2 stimulation,ALP activities of BMMSCs from lupus mice were decreased compared with the control group. The mRNA levels of ALP in lupus mice were lower than that of C3He/HeJ mice （P 〈 0.01）,while there were no differences in the Runx2 mRNA levels between the two groups after BMP-2 stimulation （P 〉 0.05）. Conclusion：BMP/Smads signaling was inhibited in the bone of lupus mouse.