苯那普利与厄贝沙坦对慢性心力衰竭大鼠主动脉内皮一氧化氮合酶及还原型辅酶Ⅱ氧化酶亚单位p22^(phox)蛋白表达的影响

Effects of Benazepril,Irbesartan on Expression of NOS and NAD(P) H Oxidase Subunit p22^(phox) of Aortic Endothelial Cells in Chronic Heart Failure Rats

目的观察苯那普利、厄贝沙坦对慢性心力衰竭(CHF)大鼠主动脉内皮氧化应激以及一氧化氮合酶(NOS)、还原型辅酶Ⅱ(NADPH)氧化酶重要亚单位p22phox蛋白表达的影响。方法采用大鼠腹主动脉缩窄法造成压力负荷性心肌肥厚致心力衰竭模型。分为5组:假手术组、未治疗组、苯那普利组、厄贝沙坦组及联合用药组。每2周测定大鼠尾动脉血压,8周后检测心功能指标及电镜观察主动脉的病理超微结构,同时采用黄嘌呤氧化酶法检测血清超氧化物歧化酶(SOD)活性,硫代巴比妥酸法测定丙二醛与硝酸还原法检测一氧化氮水平,采用匀相竞争放射免疫法测定血浆血管紧张素Ⅱ(AngⅡ)和环磷酸鸟苷(cGMP)含量,蛋白质印迹检测主动脉内皮组织NOS与NADPH氧化酶亚单位p22phox的蛋白表达。结果用药3组的主动脉病变明显减轻,内皮细胞较完整,丙二醛、左室舒张末压(LVEDP)、诱导型一氧化氮酶(iNOS)、p22phox蛋白表达均低于未治疗组(均P<0.01),且联合组比单用组低(P<0.05);一氧化氮、SOD、cGMP、左室收缩压(LVSP)、室内压最大上升速率(dp/dtmax)、室内压最大下降速率(-dp/dtmax)、内皮型一氧化氮合酶(eNOS)表达显著高于未治疗组(均P<0.05),其中联合组SOD水平比厄贝沙坦组高(P<0.05);苯那普利组血浆AngⅡ含量低于未治疗组,而联合组低于单用组(均P<0.01);整个实验过程中各治疗组之间血压无差异。结论苯那普利和厄贝沙坦单用均能改善CHF大鼠动脉内皮细胞结构及氧化应激状态,联合应用具有协同作用。

Objective To investigate the effects of benazepril,irbesartan on oxidative stress and NOS,NAD（P）H oxidase subunit p22phox expression of aortic endothelial cells in chronic heart failure（CHF）rats.Methods The model of heart failure was induced by pressure loaded myocardial hypertrophy resulted from partial coarctation of abdominal aorta in rats.The animals were divided into five groups：sham-operated controls,untreated group（Mod）,Benazepril treated group（Ben）,Irbesrtan treated group（Irb）and combined treated group（Com）.The arterial pressure was measured every two weeks.Rats were treated of 8 weeks.The pathological ultra structure changes of the aortic endothelial cells was performe with electronic micrscope.The levels of NO was detected by nitric acid reduction method and MDA by thiobarbituric acid method as well as the activity of SOD in serum by xanthine oxidase method.The serum contents of Ang Ⅱ and cGMP were determined by equalized competition radiation immunization analysis.The expression of iNOS,eNOS and p22phox protein in aortic endomembrane was tested by Western blot analysis.Results Compared with group Mod,aortic lesions were significantly reduced,and the number of intact endothelial cells are higher in group Ben,group Irb and group Com.The level of MDA in serum,left ventricular end diastolic pressure（LVEDP）,iNOS and p22phox protein levels in aortic were significantly decreased in all treated groups（P0.01）,and be more lower in group Com in comparison with group Ben and group Irb（P0.05）.The level of NO and SOD in serum,the contents of cGMP in plasma,left ventricular systolic pressure（LVSP）,dp/dtmax,-dp/dtmax,eNOS protein level in aortic were significantly increased in group Ben,group Irb and group Com in comparison with group Mod（P0.05）,and the level of SOD in serum was significantly increased in group Com in comparison with group Irb（P0.05）.The content of Ang Ⅱ in plasma was significantly reduced in comparison in group Ben and group Com in comparison with group Mod（P0.05）,and be more reduced in gruop Com in comparison group Ben and group Irb.The arterial pressure in different groups had no statistical difference.Conclusion Benazepril or（and）irbesartan improved the structure of aortic endothelial cells and attenuated oxidative stress status in CHF rats.After the combined treatment,the synergistic effect could be observed.