曲美他嗪对离体兔心肌顿抑的保护作用

Cardioprotective effects of Trimetazidine on myocardial stunning in isolated rabbit heart

目的 探讨曲美他嗪对离体兔心肌顿抑的保护作用及可能机制。方法 使用改良的非循环式Langendorff离体心灌注装置复制心肌顿抑模型 ,比较未使用曲美他嗪和分别在低温缺血停跳时 ,复灌后使用曲美他嗪对顿抑心肌心功能恢复的影响 ,同时测定缺血前和复跳前、复跳 30min后的心肌ATP含量变化 ,测定实验末的心肌含水量 ,观察心肌细胞超微结构的变化。结果 实验组的心功能各项指标恢复及对心肌的保护明显优于对照组 ,实验组间差别无显著意义 ;低温缺血停跳时使用曲美他嗪可改善顿抑心肌的ATP储备。结论 曲美他嗪可显著改善顿抑心肌的心功能。其作用机制可能与维护缺血心肌的ATP能量储备 ,调节再灌注后心肌脂肪酸及葡萄糖氧化代谢失衡 ,减轻心肌细胞损伤有关。

Objective To study the cardioprotective effects of Trimetazidine on myocardial stunning in isolated rabbit heart and explore its possible mechanisms Methods The twenty-four rabbits were randomly divided into A, B, C three groups Using a Langendorff rabbit heart model with modified K-H buffer at 37℃,all the groups were subjected to perfusion for 30 min,cold ischemia for an hour with St Thomas II cardioplegia and reperfusion for 30 min While,the group B used cardioplegia containing Trimetazidine and the group C used K-H buffer containing Trimetazidine during reperfusion The parameters of hemodynamics(HR,LVDP,±dp/dtmax)and cardiac function(RPP),the levels of myocardial ATP were measured before ischemia and during reperfusion Meanwhile, myocardial water content and ultra structure were also examined Results The recovery of hemodynamics and cardiac function except HR in experimental group were significantly better than those in control group during reperfusion (P<0 01) In addition, in comparison with the control group A,the myocardial ATP level was significantly higher in group B (P<0 01) and water content was significantly decreased (P<0 01)and the damage of myocardial ultra structure was little in experimental group Conclusion Trimetazidine can promote the recovery of cardiac function of myocardial stunning in isolated rabbit heart Its mechanisms may be associated with increasing myocardial ATP level ,intervening oxidative metabolism of glucose and fatty acid and reducing myocardial injury [