ROCKⅠ／Ⅱ基因下调对血管平滑肌细胞迁移及增殖的影响

目的：探讨ROCK亚型ROCKⅠ和ROCKⅡ对血管平滑肌细胞（A7r5）迁移及增殖的影响。方法：利用Western blot技术检测ROCKⅠ和ROCKⅡ蛋白在A7r5细胞中的表达水平；利用siRNA技术使ROCKⅠ和ROCKⅡ基因表达分别下调，并检测基因下调后蛋白表达水平；利用Boyden小室法，观察ROCKⅠ和ROCKⅡ基因下调后及ROCK特异抑制剂Y-27632对PDGF诱导的A7r5细胞迁移的影响；使用MTT法检测ROCKⅠ和ROCKⅡ基因下调后对A7r5细胞生长曲线的影响。结果：ROCKⅠ和ROCKⅡ在A7r5细胞中的蛋白表达水平不同，ROCKⅡ较ROCKⅠ的表达水平高4倍；通过对A7r5细胞进行ROCKⅠ和ROCKⅡsiRNA转染，使二者蛋白表达水平分别下调83.4％和94.7％；基因表达下调后，ROCKⅠ明显抑制了PDGF诱导的A7r5细胞的迁移，而ROCKⅡ无明显影响，Y-27632也抑制了A7r5细胞的迁移；ROCKⅠ和ROCKⅡ基因下调后对A7r5细胞生长曲线的影响无明显差别。结论：ROCKⅠ在血管平滑肌细胞迁移过程中起主导作用，ROCKⅠ和ROCKⅡ对血管平滑肌细胞的增殖作用无明显差异。

Effects of ROCK Ⅰ/ Ⅱ gene expression down-regulated on migration and proliferation of vascular smooth muscle cells

Objective： To investigate the effects of ROCK Ⅰ and ROCK Ⅱ on migration and proliferation of vascular smooth muscle cells （VSMCs） （A7r5）. Methods： The expression levels of ROCK Ⅰ and ROCK Ⅱ proteins were detected in A7r5 cells by western blot, the protein expressions of ROCK Ⅰ and ROCK Ⅱ was down regulated by siRNA transfection respectively, the effects of down-regulation of ROCK Ⅰ and ROCK Ⅱ gene expression and Y-27632 of ROCK specific inhibitor on PDGF induced A7r5 migration were detected by Boyden chamber method, the effects of down-regulation of ROCK Ⅰ and ROCK Ⅱ gene expression on A7r5 proliferation were detected by MTT assay. Results： The protein expression level of ROCK Ⅱ was four times than higher that of ROCK Ⅰ in A7r5 cells. By using siRNA transfection, the protein expression of ROCK Ⅰ and ROCK Ⅱ were down regulated by 83.4% and 94.7% respectively; ROCK Ⅰ siRNA decreased the migration of A7r5 cells, but ROCK Ⅱ siRNA had no significant effects at the same condition, and Y-27632 also decreased A7r5 migration; ROCK Ⅰ and ROCK Ⅱ siRNA have no significant differences in cell growth. Conclusion： ROCK Ⅰ, but not ROCK Ⅱ, plays an important role in VSMCs migration; ROCK Ⅰ and ROCK Ⅱ have no siguifichant differences on the proliferation of VSMCs.