中文摘要：

目的：研究不同大小的机械牵张力对成骨细胞MMP-13／TIMP-1mRNA表达的影响。方法：通过自制的多通道细胞牵张应力加载系统对小鼠成骨样细胞MC3T3-E1同时施加6％、12％和18％的机械牵张力，作用24h后，用RT—PCR方法检测细胞受力后MMP-13／TIMP-1mRNA表达的变化。结果：细胞受力后，其MMP-13／TIMP-1mRNA表达随牵张力值的增大明显增加。结论：不同大小的机械牵张力可以影响成骨细胞的MMPP-13／TIMP-1mRNA表达，进而影响骨改建。

英文摘要：

Objective To investigate the effects of different magnitudes of mechanical strain on expression of MMP-13/TIMP-1 mRNA in mouse osteoblast-like cells （MC3T3- E1） in vitro. Methods MC3T3-E1 cells were subjected to 0%, 6%, 12%, 18% elongation by using multi-passage cell stress loading system simultaneously for 24h , then MMP-13/TIMP-1 mRNA in MC3T3- E1 cells were detected by RT-PCR, Results Expression of MMP-13/ TIMP-1 mRNA in mouse osteoblast-like cells（MC3T3- E1） significantly increased in groups under strain （6%, 12%, 18% elongation） in magnitude-dependent manner compared to control after mechanical strain treatment for 24h. Conclusion Different magnitudes of mechanical strain can affect expression of MMP-13/TIMP-1 mRNA in MC3T3- E1 cells in magnitude-dependent manner, which deeply affects bone remodeling.