丝裂素活化蛋白激酶磷酸酶-1对血管平滑肌细胞增殖的影响及其机制

目的 研究丝裂素活化蛋白激酶磷酸酶-1(MKP1)对血管平滑肌细胞增殖的影响及机制。方法 转染MKP1质粒72h后，收集培养的血管平滑肌细胞(VSMC)，利用P^42／P^44磷酸化抗MAPK抗体通过免疫印迹法测定MAPK活性，用流试细胞仪测定细胞周期、细胞周期素和P27蛋白的表达。结果 转染MKP1质粒后，MAPK活性明显下降，VSMC阻滞于G0-G1期，同时抑制了细胞周期素D、E的表达，P27蛋白表达却明显增加。结论 MKP1抑制VSMC增殖可能是通过降低MAPK活性，抑制细胞周期素表达和增加P27蛋白表达途径实现的。

The Effect of Mitogen-Activated Protein Kinase Phosphatase-1 on the Proliferation of Vascular Smooth Muscle Cells and Its Mechanism

Objective To study the effect of mitogen-activated protein kinase phosphatase-1(MKP 1) on the proliferation of vascular smooth muscle cells(VSMC) and its mechanism. Methods Cultured VSMCs were collected at 72h after transfection with MKP 1 plasmid The MAPK activity was evaluated by an immunobloting technique using anti-P 42/44 phospho-MAPK antibody. Cell cycle distribution, cyclins and P27 expression were determined with flow cytometer. Results After transfection, the activities of MAPK were decreased increasingly and growth of VSMC were arrested in G 0-G 1 phase,and the cyclin D, E expression were inhibited; on the contrary,P27 expression were increased significantly. Conclusion MKP 1 inhibited the proliferation of VSMC probably by decreasing the activity MAPK, inhibiting the cyclin D,E expression and increasing the P27 expression.