血管紧张素Ⅱ受体拮抗剂对糖尿病大鼠大血管Toll样受体2表达的影响

The effect of Valsartan on the expressions of Toll-like receptor 2 in the arteria of diabetic rats

目的:研究选择性血管紧张素Ⅱ受体拮抗剂(缬纱坦)对链脲佐菌素(STZ)诱导的糖尿病(DM)大鼠大血管Toll样受体2(Toll-liker eceptor 2,TLR2)表达的影响。方法:将31只SD大鼠随机分成正常对照组(NC组)和DM造模组,造模组给予STZ60mg/(kg.次)腹腔注射,再随机分为DM组和DM+缬沙坦干预组(DV组),DV组给予缬沙坦20mg/(kg.d)灌胃。于12周时乌拉坦麻醉,取胸主动脉,用RT-PCR方法检测STZ诱导的DM大鼠大血管组织中TLR2 mRNA表达的变化,Western blot检测大血管中TLR2蛋白表达的变化。结果:与NC组相比,DM组和DV组大鼠的血糖明显升高(P<0.01),而DM和DV组间血糖差异无显著性(P>0.05);DM大鼠大血管组织中TLR2 mRNA和蛋白的表达明显高于NC组(均P<0.01),而DV组大血管组织中TLR2 mRNA和蛋白的表达明显低于DM组(P<0.01),差异均具有显著性。结论:DM大鼠大血管组织中存在TLR2表达的增加,缬纱坦可能通过降低血管组织TLR2表达而对糖尿病大血管炎性改变起防治作用。

Objective：To investigate the effect of Valsartan on the expressions ofToll-like receptor（TLR） 2 in the arteria of streptozotocin（STZ） induced diabetic rats. Methods ：Thirty-one Sprague-Dawley rats aged 8 weeks were assigned randomly to receive STZ at a dose of 60 mg/kg intraperitoneally（diabetes, n = 24） or citrate buffer alone（normal eontrols,NC,n = 7）. One week after injection, only STZ- treated rats with plasma glucose concentrations above 16.7 mmol/L were considered diabetic and were subsequently dividied into two groups：diabetic group and DV group which received Valsartan 20 mg/（kg·d） intragastriely. At 12th week, the rats in three groups were sacrificed for their arteria and blood samples. The expressions of TLR2 mRNA were determined by reverse transcription PCR. The protein levels of TLR2 were detected by Western blot. Results：Compared with NC group, the levels of blood glucose in DM and DV groups increased significantly （P 〈 0.01 ）, but no notable difference was found in the levels of blood glucose between DM and DV group（P 〉 0.05）. The expressions of TLR2 mRNA and protein in DM group were much higher than that in NC group（P 〈 0.01 ）, but it was much lower in DV group than that in DM group （P 〈 0.01 ）. Conclusion：The expressions of TLR2 mRNA and protein were much higher in the arteria of diabetic rats, Valsartan could obviously reduce the expression of TLR2 in the arteria of diabetic rats which implicates that it might be able to ameliorate the early inflammatory reaction in the arteria of the rats with diabetes.