辛伐他汀对大鼠心肌梗死后心室重塑影响的实验研究

目的探讨辛伐他汀对大鼠心肌梗死后心脏功能和心室重塑的影响。方法结扎大鼠冠状动脉前降支建立心肌梗死模型,24 h后存活大鼠随机分成心肌梗死组(M I组)、辛伐他汀20 mg组(20 mg.kg-1.d-1)和40 mg组(40 mg.kg-1.d-1),另单设假手术组(Sham组)。8 wk后测定血液动力学指标,血清血脂水平,心室重量指数,苦味酸天狼猩红染色后观察心脏形态学改变,测定心肌胶原容积分数。结果各组血脂水平无统计学差异;MI组心室重量指数增加,心脏收缩及舒张功能受损,梗死边缘区胶原沉积明显,胶原比例改变。两个辛伐他汀(simvastatin,Sim)组均能减轻心室重量指数,改善心脏功能,减少梗死边缘区胶原沉积。结论辛伐他汀能抑制心肌梗死后心室重塑,其机制可能与抑制心肌梗死后心肌肥大和心肌间质纤维化相关,而与其降脂作用关系不大。

Effect of simvastatin on left ventricular remodeling and heart function in rats with myocardial infarction

Aim To study the effect of simvastatin(Sim) on left ventricular remodeling and heart function in rats with myocardial infarction(MI).Methods Myocardial infarction models were successfully induced by ligation of anterior descending coronary artery.24 h later the survivals were randomly divided into 3 groups.① MI group;② 20 mg Sim group(20 mg·kg~(-1)·d~(-1));③ 40 mg Sim group(40 mg·kg~(-1)·d~(-1)).The rats with sham ligation formed sham group.After 8 weeks,hemodynamic parameters,blood serum lipids,the ratio of RV and LV weight to body weight(RVWI,LVWI) were examined.The pathomorphological change and the collagen volume fraction(CVF) were analyzed by PSR dyeing.Results There were no significant differences in values of serum lipids among 4 groups.Compared with sham group,the left ventricular end-diastolic pressure(LVEDP) was increased and left ventricular systolic pressure(LVSP) was depressed significantly in MI group; the RVWI and LVWI and the CVF in border infarcted zone and Ⅰ/Ⅲ ratio were increased in MI group too.Compared with MI group,Sim partially normalized LVSP and LVEDP;abated ventricular weight index;reduced CVF in non-infarction zone in both Sim groups.Conculusion Simvastatin improves LV remodeling and heart function in rats with MI,which is associated with the effect of limiting myocardial hypertrophy and interstitial fibrosis.