中文摘要：

目的：研究人G蛋白偶联受体激酶4（GRK4）变异体 A142V对大鼠血管平滑肌细胞（VMSCs）血管紧张素Ⅱ1型（AT1）受体及其介导的VMSCs增殖的影响，以期了解 GRK4引起原发性高血压的原因。方法构建与增强型绿色荧光蛋白（EGFP）融合表达的慢病毒载体，包装慢病毒，感染A10细胞并进行鉴定；免疫印迹方法检测 AT1受体蛋白变化；采用分光光度法检测GRK4活性，免疫共沉淀检测 GRK4和 A T1受体的共连接；[3 H ]胸腺嘧啶掺入的方法检测增殖变化。结果转染hGRK4γA142V细胞的GRK4酶活性显著升高，AT1受体表达显著升高，GRK4和AT1受体共连接作用降低，AngⅡ刺激细胞增殖效应显著增强。结论转染hGRK4变异体A142V增加GRK4活性，引起AT1受体的功能增强和VMSCs的增殖作用增加。

英文摘要：

Objective To study the effect of human G-coupled protein kinase 4（GRK4） A142V overexpression on angiotensin Ⅱ1 type（AT1 ） receptor and its-mediated proliferation of rat vascular smooth muscle cells .Methods We constructed a lentiviral vec-tor carrying human GRK4-EGFP gene and observed its expression in A10 cells .Expression of AT1 receptor were determined by im-munoblotting ,GRK4 activity were checked by spectrophotometry ;the linkage between GRK4 and AT1 receptor were determined by co-immunoprecipitation .[3 H] thymidine incorporation was used to detect changes of cell proliferation .Results As compared with the control cells ,A142V-transfected cells had higher GRK4 activity and higher AT1 receptor expression ;there was linkage between GRK4 and AT1 receptor ,the co-immunoprecipitation levels were lower in A142V cells .The basal levels of VSMC proliferation was higher in A142V cells ,Ang Ⅱ increased VSMC proliferation to a greater extent in A 142V cells .Conclusion GRK4 A142V ,via in-creasing GRK4 activity ,increases AT1 receptor expression and function in vascular smooth muscle cell proliferation .