卡维地洛与倍他乐克防治大鼠AMI左室重构作用的比较

目的对比卡维地洛及倍他乐克对大鼠急性心肌梗死(AMI)左室重构(LVRM)的防治作用.方法 105只AMI术后成活的雌性SD大鼠随机分成AMI对照(n=35)、卡维地洛1 mg/(kg@d)(n=35)和倍他乐克2 mg/(kg@d)(n=35)三组.另设假手术组.给药4周后行血流动力学测定和病理分析.去除死亡及梗死面积＜35%或＞55%者,最终46只大鼠资料完整,在以上各组分别为11,12,11和12只.结果与假手术组相比,AMI组的左室舒张末压(LVEDP)、容积(LVV)、重量(LVW)显著增加(P＜0.05～0.111),左室内压最大上升和下降速率(±dp/dt)及其校正值(±dp/dt/LVSP)显著降低(P＜0.01～0.001).与AMI组相比,卡维地洛和倍他乐克组的LVEDP及LVV均显著降低(P均＜0.001),±dp/dt及±dp/dt/LVSP均显著升高(P＜0.05～0.001),而LVW和RVW仅在卡维地洛组显著减轻(P均＜0.05～0.01).结论 1、卡维地洛能有效抑制大鼠AMI左室重构并改善血流动力学和左室功能,2、倍他乐克与卡维地洛的作用相似,但对心室肥厚似无抑制作用.

Comparative effects of carvedilol and metoprolol in preventing from left ventricular remodeling after acute myocardial infarction in rats

OBJECTIVE: To compare the effects of carvedilol and metoprolol in preventing from left ventricular remodeling (LVRM) after acute myocardial infarction (AMI) in rats. METHODS: Twenty-four hours after ligating left coronary artery, 105 surviving female SD rats were randomly assigned to AMI control, carvedilol 1 mg/(kg.d) and metoprolol 2 mg/(kg.d) groups. Sham-operated rats (n = 16) were selected randomly as non-infarction control. After four weeks of drugs therapy, hemodynamic studies and pathologic analysis were performed. Exclusive of MI size < 35% or > 55%, complete experimental variables were obtained in 46 rats, which were comprised of AMI (n = 11), carvedilol (n = 12), metoprolol (n = 11), and Sham-operated (n = 12) groups. RESULTS: Compared with sham-operated group, left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV) and weight (LVW), were all significantly increased (P < 0.05-0.001), while maximal rate of rise and fall (+/- dp/dt) of LV pressure as well as their corrected values (+/- dp/dt/LVSP) were all significantly decreased (P < 0.01-0.001) in AMI group. In comparison with AMI group, the LVEDP and LVV were all significantly decreased (all P < 0.001), while +/- dp/dt and +/- dp/dt/LVSP were significantly increased (P < 0.05-0.001) in both carvedilol and metoprolol group, with LVW and RVW only decreased in carvedilol group (P < 0.05-0.01). CONCLUSIONS: 1. Carvedilol can effectively attenuate LVRM, and improve hemodynamics and LV function after AMI in rats, 2. Metoprolol has equivalent beneficial effects as carvedilol on hemodynamics, LV dilatation and function, but not LV hypertrophy.