血管紧张素Ⅱ-NADPH氧化酶-活性氧通路在慢性心肌缺血血瘀证中作用的实验研究

Experimental study on role of AngII-NADPH oxidase-ROS pathway in syndrome of blood stasis based on chronic myocardial ischemia model

目的:观察血管紧张素Ⅱ-NADPH氧化酶(NADPH oxiase)-活性氧通路在慢性心肌缺血血瘀证发生发展中的作用。方法:采用中华小型猪左冠状动脉前降支放置Ameroid缩窄环的方法制备慢性心肌缺血血瘀证模型。小型猪随机分为假手术组、模型组,动态观察模型动物心肌缺血(0-4周)四诊体征与血液流变学指标,采用冠脉造影测定心肌缺血的程度;Elisa方法测定血浆血管紧张素Ⅱ(AngⅡ)、醛固酮(Ald)含量以及氧化应激关键分子NADPH氧化酶、活性氧(ROS)、超氧物歧化酶(SOD)的浓度变化。结果:该模型在4周确定为稳定的病证结合慢性心肌缺血血瘀证模型,血瘀证形成时肾素-血管紧张素-醛固酮系统(RAAS)中,AngⅡ和Ald分别上升了14.10%和56.25%。NADPH氧化酶和代表ROS含量变化的丙二醛(MDA)分别上升了43.75%和9.24%,SOD下降了11.55%(P<0.05),相关性分析发现,AngⅡ与NADPH氧化酶呈正相关(P<0.05),NADPH氧化酶与MDA呈正相关(P<0.05),AngⅡ与MDA呈正相关(P<0.01)。结论:该模型制备的慢性心肌缺血血瘀证,早期的病理机制包括RAAS系统的激活以及氧化应激损伤反应。其中,AngⅡ-NADPH氧化酶-ROS之间存在着正相关关系。AngⅡ介导NADP氧化酶浓度的升高,进一步增加NADPH氧化酶来源的ROS生成,RAAS系统的激活与氧化应激反应互为因果,进而导致了血瘀证的临床改变,及早干预该环节可提高慢性心肌缺血血瘀证的临床疗效。

Objective： To inquire the roles of AngiotensinⅡ-NADPH oxidase-reactive oxygen species（ROS） pathway in the genesis and development of blood stasis syndrome with myocardial ischemia.Methods： Miniature swine were randomly divided into sham operation group and model group,the dynamic observation of animal models（0-4 weeks） were taken to collect the four diagnostic information,hemorheology and coronary angiography were used to measure the extent of myocardial ischemia,Elisa to determine the concentration of key molecules in oxidative stress and RAAS such as angiotensin（AngⅡ）,aldosterone（Ald）,NADPH oxidase,superoxide dismutase（SOD）,malondialdehyde（MDA）.Results： The blood stasis syndrome is expressed steadily in 4th week,suggesting for a stable combination of blood stasis Syndrome with chronic myocardial ischemia model.Tongue color and blood hemorheology changed significantly in this stage.Among them,compared with the sham-operated group,AngⅡ and Ald rose by 14.1% and 56.25% respectively.NADPH oxidase and MDA which represents ROS concentration,were increased by 43.75% and 9.24% respectively,activity of antioxidant enzymes as SOD expressed in the model group decreased by 11.55%,which were significantly different（P〈0.05）.Correlation analysis found that,AngⅡ and NADPH oxidase showed a strong positive correlation（P〈0.05）,NADPH oxidase and MDA was positively correlated（P〈0.05）,AngⅡ showed a strong positive correlation with MDA（P〈0.01）.Conclusion： The early pathological mechanisms included RAAS system activation and oxidative stress damage response.The AngⅡ-NADPH oxidase-ROS existed strong positive correlation.AngⅡ mediated the increase of NADPH oxidase concentration,which further increased the generation of NADPH oxidase-derived ROS,the activation of RAS system and oxidative stress based on each other which leading to change of blood stasis syndrome,finally exacerbated the pathological process of blood stasis syndrome with myocardial ischemia,early intervention may improve the clinical efficacy.