氯沙坦对自发性高血压大鼠血管内氧化应激态的影响

Effect of losartan on oxidative stress in vessels of rats with spontaneous hypertension

目的:探讨氯沙坦对自发性高血压大鼠(spontaneoushypertensionrats,SHR)血浆一氧化氮、一氧化氮合酶(nitricoxidesynthase,NOS)、超氧化物歧化酶(superoxidedismutase,SOD)和活性氧的影响。方法:30只实验动物分为3组,其中10只Wistar京都大鼠(WKY)为正常血压组,20只SHR随机分为SHR组和使用氯沙坦SHR组。氯沙坦灌胃8周后,取血浆采用化学比色法测定一氧化氮和活性氧的含量及NOS,SOD活性。结果:SHR组与正常血压组比较,血浆活性氧含量和NOS活性显著增高(t=52.15,6.87,P<0.001),一氧化氮含量和SOD活性显著降低(t=4.60,6.60,P<0.001);氯沙坦SHR组活性氧含量犤(864.6±24.8)kU/L犦比SHR组犤(2134.8±87.6)kU/L犦显著降低(t=44.11,P<0.001),一氧化氮含量增高(t=3.09,P<0.05),但SOD和NOS的活性变化,差异无显著性意义(P>0.05)。结论:高血压可能是血管内氧化应激态形成的重要因素之一,而氯沙坦对这种状态有抑制作用,有利于内皮功能的改善。

AIM:To explore the effect of losartan on the expression of plasma nitric oxide(NO),nitric oxide synthase(NOS),superoxide dismutase(SOD) and reactive oxygen species(ROS) in rats with spontaneous hypertension. METHODS:Twenty spontaneously hypertension rats(SHR) were randomly divided into SHR group and losartan SHR group and 10 WKY rats were taken as the normal blood pressure group.After treated with the intragastric infusion of losartan for 8 weeks,chemical colorimetry was applied to measure the plasma contents of NO and ROS,and activities of NOS and SOD. RESULTS:Compared with the normal blood pressure group,the plasma ROS content and NOS activity were increased significantly(t=52.15,6.87,P< 0.001),while the NO content and SOD activity were significantly decreased(t=4.60,6.60,P< 0.001) in the SHR group.The content of ROS in the losartan SHR group[(864.6±24.8)kU/L] was significantly decreased compared with the SHR group[(2 134.8±87.6)kU/L](t=44.11,P< 0.001), and NO content increased(t=3.09,P< 0.05),while there was no significant difference in the changes of SOD and NOS activities(P >0.05). CONCLUSION:Hypertension may be one of the important factors of the formation of intravascular oxidative stress,however,losartan can inhibit the oxidative stress,which is beneficial to the amelioration of endothelial function.