中文摘要：

目的：观察二氧化硫（SO2）吸入对运动大鼠心肌收缩力的影响并分析其可能机制。方法：48只SD大鼠随机分为空白对照组（RG）、单纯运动组（EG）、单纯S02污染组（SRG）和SO2污染运动组（SEG），每组12只。SRG组和SEG组置于S02污染环境（10mg／m2）中1h／d，共4周；EG组和SEG组进行电动跑轮运动（8m／min，1h／d，连续4周）。实验结束后，称量大鼠体重、心脏重量，并利用公式计算心脏重量指数和体重增长率。采用心脏插管技术测定各组大鼠血液动力学参数：采用放射免疫技术测定各组大鼠心肌AngII含量；采用免疫组织化学技术测定各组大鼠心肌AT1R含量。结果：EG组大鼠心脏重量指数、主动脉收缩压（SBP）、脉压差（PP）、左室内压峰值（LVSP）、左室内压最大上升速率（＋dp／dtmax）、左室内压最大下降速率（-dp／dtmax）显著高于RG组（P〈0．01），舒张压（DBP）、心率（HR）、心肌AT1R蛋白表达水平显著低于RG组（P〈0．01，P〈0．05）；SRG组和SEG组大鼠心脏重量指数、左室末期舒张压（LVEDP）、心肌AngII含量、AT1R蛋白表达显著高于RG组（P〈0．05。P〈0．01），＋dp／dtmax显著低于RG组（P〈0．01）；SEG组大鼠SBP、PP、LVSP显著低于RG组（P〈0．01），HR显著高于RG组（P〈0．01）；且SEG组大鼠HR、LVEDP、心肌AngII含量、AT1R蛋白表达显著高于SRG组（P〈0．01），SBP、PP、LVSP、＋dp／dtmax显著低于SRG组（P〈0．01）。结论：SO2污染对运动大鼠心脏收缩功能产生显著负性变力性效应．AngII及其受体AT1R蛋白表达水平上调引起RAS系统功能紊乱是导致运动大鼠心肌收缩力降低的原因之一。

英文摘要：

Objective The aim of this study function of exercising rats. Methods Forty eight was to observe the effect of SO2 inhalation on cardiac SD rats were equally divided into 4 groups randomly： rest group （RG）, exercise group （EG）, SO2 inhalation group （SRG） and SO2 inhalation plus exercise group （SEG）. Rats in groups SRG and SEG were exposed to the SO2 polluted environment （10 mg/m3, 1 h/d） for 4 weeks. And the rats in groups EG and SEG were trained with motor driven wheel （8 m/min, 1 h/d） for 4 weeks. The body weight and the heart weight of rats were obtained and the cardiac index and body weight growth rate were calculated with the corresponding formula after the experiment. Hemodynamic parameters were detected through heart catheterization. The concentrations of Aug II and of AT1R in myocardium were tested by radioimmunity technique and immunohistochemistry. Results As compared with group RG,cardiac index,SBP,PP,LVSP and ＋dp/dtmax in group EG increased significantly （P 〈 0.01） ,while DBP,HR and concentrations of Ang II and AT1R in myocardium decreased significantly （P 〈 0.01,P 〈 0.05）. Cardiac index,LVEDP and concentrations of Ang II and AT1R of myocardium were significantly higher （P 〈 0.05 ,P 〈 0.01 ） and ＋dp/dtmax was significantly lower （P 〈 0.01 ） in groups SRG and SEG than that in group RG. Meanwhile,SBP,PP and LVSP reduced significantly,and HR remarkably increased in group SEG as compared with that in group RG （P 〈 0.01 ）. HR, LVEDP and concentrations of Ang II and AT1R of myocardium in group SEG were higher than that in group SRG （P 〈 0.01 ） ,while SBP,PP,LVSP and ±dp/dtmax in group SEG were lower than that in group SRG（P 〈 0.01 ）. Conclusion Exercise in SO2 polluted environment negatively affects the myocardial contractility based on the upregulation of Aug II and AT1R expression and the disturbance of renin-angiotensin system.