缬沙坦对兔髂动脉内皮损伤后转化生长因子β_1表达的影响

Effect of valsartan on expression of transforming growth factor-β_1 after balloon injury in rabbits

目的 探讨血管紧张素Ⅱ(AngⅡ)受体拮抗剂缬沙坦对兔髂动脉内皮损伤后转化生长因子β1(TGF-β1)表达的影响。方法 新西兰兔24只随机平分为3组,普通饲料喂饲组(G1),高脂饮食喂饲+动脉内皮损伤组(G2),高脂饮食喂饲+动脉内皮损伤+缬沙坦治疗组(G3),G2、G3应用球囊损伤髂动脉内皮加高脂饲养的方法建立兔动脉粥样硬化狭窄模型,术后4周采用免疫组织化学和反转录聚合酶链反应(RT—PCR)技术对兔髂动脉壁TGF-β1表达的情况进行观察。结果 G2、G3TGF-β1蛋白和TGF-β1mRNA表达均显著高于G1,而G3 TGF-β1蛋白和TGF-β1mRNA表达显著低于G2(P<0.01)。此外,还观察到TGF-β1mRNA表达水平与内膜/中膜比值呈正相关(r=0.941,P<0.01)。结论 缬沙坦对内皮损伤后的血管病变有部分保护作用,其机制可能是部分通过下调TGF-β1的表达,减轻血管损伤后新生内膜的增生。

Objective To investigate the effect of Valsartan on expression of transforming growth factor-β1 after balloon injury in rabbits. Methods The following groups of rabbits were studied: ordinary feeding rabbits(G1) .cholesterol feeding+iliac artery injury rabbits(G2) and cholesterol feeding+iliac artery injury+ Valsartan treatment rabbits(G3). A reproducible rabbit model was established with cholesterol feeding after iliac artery injury induced by an inflated balloon catheter. The expression of transforming growth factor-β1 (TGF-β1) in the iliac artery was observed by immunohisto-chemistry and reverse transcription polymerase chain reaction (RT-PCR) after 4 weeks of iliac artery injury. Results Compared to Gl there was a significant increase in protein and mRNA expression of TGF-β1 in G2 and G3. The mRNA expression of TGF-β1 as well as the protein expression of TGF-β1 in G3 were much lower than in G2. Besides,a positive correlation was found between mRNA expression of TGF-β1 and intimal/medial(I/M) ratio(r=0. 941,P<0. 01). Conclusion Valsartan has some protective effect on the balloon-injured arteries of rabbits partly through down-regulating TGF-β1 expression and reducing proliferation of neointima.