血管紧张素Ⅱ对大鼠血管平滑肌细胞弗林蛋白酶表达的影响

Effects of angiotensinⅡon furin expression in cultured rat vascular smooth muscle cells

目的研究血管紧张素Ⅱ(AngⅡ)对体外培养的大鼠血管平滑肌细胞(VSMCs)弗林蛋白酶表达的影响,初步探讨在高血压中,AngⅡ导致纤维化病变形成的作用机制。方法选择体外培养大鼠VSMCs,按实验方案给予不同浓度AngⅡ作用24 h后,采用实时定量PCR和Western blot法,检测各组细胞弗林蛋白酶mRNA及蛋白的表达量;用荧光分析法检测各组弗林蛋白酶的活性。本实验共分为5组;对照组、AngⅡ10^(-7)mol/L组、AngⅡ10^(-6)mol/L组、AngⅡ10^(-5)mol/L组、AngⅡ10^(-4)mol/L组。结果与对照组比较,不同浓度AngⅡ组弗林蛋白酶mRNA表达量及活性均明显升高,AngⅡ10^(-5)mol/L组和AngⅡ10^(-4)mol/L组升高更明显,AngⅡ10^(-4)mol/L组达到最大值(P<0.05,P<0.01)。结论 AngⅡ能够促进大鼠VSMCs中弗林蛋白酶的表达,AngⅡ可能通过促进弗林蛋白酶的表达,使活性转化生长因子β产生增加从而促进纤维化病变的形成。

Objective To investigate effect of angiotensin Ⅱ （Ang Ⅱ ） on the expression of furin in cultured rat vascular smooth muscle cells（VSMCs） ,so that to illustrate the mechanism of fibrotic effects of Ang Ⅱin hypertension. Methods VSMCs were cultured in DMEM and then were stimulated with Ang Ⅱas indicated. Furin mRNA and protein expression were examined by RT-PCR and Western blot. Furin activity was determined using fluorescent Furin-substrate Boc-RVRR- amc by the release of the fluorescent amc moiety,measured with a fluorospectrometer. All statisti- cal analyses were preformed using SPSS 10.0 software. Differences with P〈0.05 were considered as statistically significant. Results Ang Ⅱ enhanced furin expression. What is more,furin expres- sion in 10^-7 mol/L and 10^-4 mol/L Ang Ⅱ groups was extremely higher than that of control group（P〈 0.05 ,P〈0.01）,with the highest expression found in the 10^-4 mol/L Ang Ⅱ group. Conclusion Ang Ⅱ upregulates furin expression in cultured VSMCs. Ang Ⅱ may enhance activity of TGF-β by stimulating furin expression,leading to fibrosis of blood vessels in hypertension.