目的:探索机械牵张应力对人成骨肉瘤细胞MG-63中RhoA/ROCK信号通路的影响。方法:将同一条件培养的细胞MG-63分为实验组(加力)与对照组(不加力),实验组采用Flexcell牵张应力加载系统,选择12%形变率作为加载应力值,分为五个时间组,分别加载1 h,4 h,8 h,12 h,24 h,RT-PCR检测RhoA、ROCK mRNA水平表达的变化,Western-Blot检测RhoA与Rock蛋白含量变化。结果:RT-PCR显示MG-63细胞受应力刺激后1 h RhoA、ROCK均未见明显变化(P>0.05),4小时后略有升高(P<0.05),在8 h达到最大值(P<0.05),12、24 h降低,但仍高于对照组(P<0.05);Western-Blot显示MG-63细胞受应力刺激后1 h RhoA、ROCK均未见明显变化,4 h仍未见明显变化,在8 h达到最大值,12、24 h降低,高于对照组。结论:机械牵张力加载下MG-63细胞内RhoA、ROCK表达升高并随时间增加出现峰值,提示其可能在成骨细胞力学信号转导过程中发挥重要作用。 Objective: To investigate the effect of mechanical stretch stress on RhoA / ROCK signaling pathway in human osteosarcoma cell line MG-63. Methods: The cells cultured in the same condition were divided into experimental group (with force) and control group (without force). Flexcell stretch stress loading system was used in the experimental group. The 12% deformation rate was selected as the loading stress and divided into The expression of RhoA and ROCK mRNA was detected by RT-PCR at 1h, 4h, 8h, 12h and 24 h respectively. The contents of RhoA and Rock protein were detected by Western-Blot. Results: There was no significant change in RhoA and ROCK at 1 h after MG-63 cells were stimulated by RT-PCR (P> 0.05), but slightly increased at 4 h (P <0.05) and reached the peak at 8 h P <0.05), but decreased at 12 and 24 h (P <0.05). Western-Blot showed that there was no significant change in RhoA and ROCK at 1 h after stress-induced in MG-63 cells, See significant changes, reaching the maximum at 8 h, 12,24 h decreased, higher than the control group. CONCLUSION: The expression of RhoA and ROCK in MG-63 cells induced by mechanical strain increases and peaks with time, suggesting that it may play an important role in the signal transduction of osteoblasts.