ACE抑制剂卡托普利对实验性围手术期心肌缺血的影响

目的:图手术期心肌缺血主要是因为应激引起冠状动脉内皮功能障碍所致,所以观察卡托普利对其影响。方法:杂种犬20只均分为4组:Ⅰ组(对照组),Ⅱ组(心肌梗塞模型组),Ⅲ组(心梗 胃大部切除术)和Ⅳ组(心梗 卡托普利 胃大部切除术)。心梗2周后行胃大部分切除术,测定Ⅲ、Ⅳ两组的基础状态、术前和术后的血流动力学指标、血浆内皮素(ET)及一氧化氮(NO)。用组织原位杂交方法观察4组非梗塞区冠脉内皮-氧化氮合酶(NOS)mRNA表达水平。结果:在Ⅲ组,手术使LV dP/dt_(max)、心脏指数(CI)及NO下降,引起LVEDP、PCWP、总外周阻力(TPR)、左室舒张压力下降时间常数(T值)和ET升高。在Ⅳ组,用卡托普利后40min,TPR下降,T值升高;手术使血流动力学指标回降,不影响其它指标。组织原位杂交示,NOS mRNA在Ⅰ组高度表达,Ⅱ组和Ⅳ组次之,Ⅲ组最低。结论:卡托普利能预防胃大部切除术引起的左室舒缩障碍和冠脉内皮功能障碍。

Effects of angiotensin converting enzyme inhibitor captopril on experimental penoperative myocardial inchemia

OBJECTIVE: The perioperative myocardial ischemia (PMI) is mainly caused by increase in sympathetic nervous system activity due to stress, which results in coronary endothelial dysfunction, so it is investigated that the effect of captopril on PMI.METHODS:Twenty mongrel dogs were randomized for four groups:group I :control group;group II : myocardial infarction (MI) model;group III :MI partial gastrectomy; group IV : MI captopril partial gastrectomy. In the group HI and IV,the hemodynamics,plasma endothelin(ET) and nitric oxide(NO) on baseline,pre-and postoperaion were investigated two weeks after MI. All animals were killed by overdose anesthetic and their cardiac samples of non-infarcted area for examining nitric oxide synthase (NOS) mRNA expression levels in vascular endothelial cells. RESULTS: In the group III,the operation decreased the maximal rate of left ventricular presure rise(LV dP/dtmax, cardiac index(CI) and plasma NO level,and increased left ventricular end diastolic pressure(LVEDP),time-course of isovolumic pressure fall(T constant),total peripheral resistance (TPR) and the levels of ET. In the group IV, 40 minutes after administration of captopril,the TPR was decreased, and the T constant was increased significantly, the operation attenuated the TPR and T constant, but did not affect other values. In situ hybridization it was showed that the expressive levels of NOSmRNA was the highest in the group I , lower in the group II and IV , and the lowest in th egroup III. CONCLUSIONS: Captopril can improve the left ventricular and endothelial dysfunction induced by the partial gastrectomy performed after myocardial infarction.