同型半胱氨酸在大鼠血管平滑肌细胞上通过激活ERK1/2信号通路促进血管紧张素Ⅱ受体1表达  

Homocysteine upregulates angiotensinⅡreceptor type 1(AT1R) expression via activating ERK1/2 signaling pathway in rat vascular smooth muscle cells

作　　者：姜衡[1] 于曼丽[2] 魏勇[1] 欧阳平[1] 梁春[3] 吴宗贵[3] 

机构地区：[1]上海交通大学附属第一人民医院松江分院心内科,上海201600 [2]第二军医大学长海医院心内科,上海200433 [3]第二军医大学长征医院心内科,上海200003

出　　处：《第二军医大学学报》2014年第9期968-973,共6页Academic Journal of Second Military Medical University

基　　金：上海市松江区科委科学技术攻关项目(12SJGGYY02)~~

摘　　要：目的观察同型半胱氨酸(homocysteine,Hcy)对大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMCs)血管紧张素Ⅱ受体1(angiotensinⅡreceptor type 1,AT1R)蛋白表达的影响。方法从大鼠胸主动脉分离、培养VSMCs,并用平滑肌特异性肌纤蛋白(α-SMA)进行免疫荧光鉴定;用10、100和300μmol/L 3个不同浓度的Hcy孵育VSMCs,或在加入Hcy的同时加入5μmol/L的ERK1/2通路阻断剂U0126,48h后用免疫印迹法检测磷酸化的ERK1/2及AT1R的蛋白表达。结果经鉴定,成功分离、培养VSMCs。10、100和300μmol/L 3个不同浓度的Hcy均可上调VSMC的AT1R蛋白表达量(与溶剂对照组比较,P<0.05)。但3个浓度的Hcy组间差异无统计学意义(P>0.05)。10μmol/L的Hcy可增加VSMC的ERK1/2磷酸化(P<0.05),激活ERK1/2信号通路。ERK1/2通路抑制剂U0126可完全阻断Hcy导致的ERK1/2磷酸化,并取消Hcy导致的AT1R上调。结论 Hcy可通过激活ERK1/2信号通路促进大鼠VSMC AT1R的表达,这一结果可能有助于揭示高Hcy血症与高血压的内在联系。Objective To study the influence of homocysteine on the protein expression of angiotensinⅡ receptor type 1(AT1R)in rat vascular smooth muscle cells(VSMCs).Methods Primary rat VSMCs were isolated and cultured in vitro and identified by detectingα-SMA expression with immunofluorescence technique.VSMCs were exposed to three different concentrations of homocysteine(10,100 and 300μmol/L)alone or in combination with U0126(5μmol/L,apotent inhibitor of ERK1/2)for 48 h,and then immunoblotting method was used to detect AT1 Rprotein expression and phosphorylation of ERK1/2.Results Primary rat VSMCs(positive forα-smooth muscle actin [α-SMA]staining)were isolated and cultured successfully.All the three different concentrations of homocysteine(10,100 and 300μmol/L)induced significant AT1 Rprotein expression(P<0.05 vs solvent control group)in VSMCs,but there was no significant difference between the three groups.Moreover,homocysteine at 10μmol/L significantly activated phosphorylation of ERK1/2in VSMCs(P<0.05 vs blank control).Supplement of U0126 not only blocked the phosphorylation of ERK1/2induced by homocysteine,but also abolished homocysteine-induced upregulation of AT1 R.Conclusion Our results in this study indicate that homocysteine can upregulateAT1 Rprotein expression via activating ERK1/2signaling pathway in rat VSMCs,which may help to illustrate the relation between Hcy and hypertension.

关 键 词：高血压 同型半胱氨酸 血管平滑肌细胞 ERK1/2 血管紧张素Ⅱ受体1 

分 类 号：R544.1[医药卫生—心血管疾病]