曲美他嗪对慢性心衰家兔心肌能量代谢的影响及其保护作用

目的探讨曲美他嗪（TMZ）对慢性心衰家兔心肌能量代谢的影响及其保护作用。方法新西兰兔30只,随机分为4组：假手术组（n=6）,手术组（n=8）：结扎腹主动脉复制心衰模型,手术给药组1（TMZ,n=8）,手术给药组2（卡托普利,n=8）,分别于术后第4天口服给药。实验8周后,观察TMZ对家兔慢性心衰时心脏血流动力学各项指标（HR、LVSP、LVEDP、±dp/dt（max））及心肌高能磷酸盐（ATP、PCr）代谢的影响,同时比较血浆心钠素水平、心质量指数的变化。结果（1）与假手术组相比,手术组发生不同程度的心衰症状,表现为心脏收缩功能的减退,心肌肥厚,血浆心钠素水平显著升高,同时心肌高能磷酸盐含量显著减少（均P〈0.01）。（2）手术给药组（TMZ、卡托普利）的血流动力学各项指标明显优于手术组,且心肌肥厚明显减轻,血浆心钠素水平明显下降,心肌高能磷酸盐含量明显增加（均P〈0.05）,给药组组间比较差异无统计学意义（P〉0.05）。结论TMZ可显著改善慢性心衰心脏的心功能,减轻心肌肥厚,其作用机制可能与增加心衰心肌内的高能磷酸盐储备有关。

Effects of Trimetazidine on Myocardial Metabolism in Rabbits with Experimental Congestive Heart Failure and Its Cardioprotective

Objective To study the effects of trimetazidine（TMZ） on myocardial metabolism in rabbits with congestive heart failure and its cardioprotective effect. Methods Thirty rabbits were randomly assigned to four groups ： the sham group （ SH, n = 6 ）, operation group （ OP, n = 8 ）, TMZ group （ TMZ, n = 8 ） and captopril group （captopril , n = 8 ）. Except sham group, the rabbit model with congestive heart failure was produced by constricting abdominal aorta. TMZ was given in TMZ group four days after operation and captopril in captopril group. The parameters of hemodynamics （ HR, LVSP, LVEDP, ＋ dp/dtmax ） and the content of myocardial high energy phosphate （ ATP, PCr） were measured after 8 weeks of treatment. Meanwhile, Heart and LV weight to body weight ratio and ANP in hematoplasma were also examined. Resuits With sham group, the cardiac contractile function in operation group were significantly decreased, the myocardial hypertrophy emerged, the level of plasma ANP were significantly higher and the myocardial ATP,PCr level was significantly lower after 8 weeks （P 〈 0.01 ）. Nevertheless, in comparison with the operation group, in TMZ and captopril group the cardiac contractile function and the myocardial ATP, PCr level were significantly increased, the level of plasma ANP was significantly lower and the myocardial hypertrophy was lessen （ P 〈 0.05 ）. Conclusion Trimetazidine can promote cardiac contractile function in rabbit with congestive heart failure . Its mechanisms may be associated with increasing myocardial ATP level.