N-乙酰半胱氨酸改善大鼠心肌梗死后心室结构重塑的研究

目的：探讨N-乙酰半胱氨酸（N-acetylcysteine,NAC）对大鼠心肌梗死（myocardial infarction,MI）后心室结构重塑的影响及其潜在机制。方法：Sprague-Dawley（SD）大鼠96只,随机分为空白对照组（blank control,BC组）6只,余90只制作心肌梗死模型,成功存活24小时后随机分为NAC干预组（NAC）34只,生理盐水对照组（NS）32只,NAC组腹腔注射NAC0.2 mg·kg-1.2d-1],NS组腹腔注射同等剂量的生理盐水。连续干预4周后,超声心动图检测大鼠收缩期左室后壁厚度（systolic left ventricular posterior wallthickness,LVPW;s）,舒张期左室后壁厚度（diastolic left ventricular posterior wall thickness,LVPW;d）,收缩期室间隔厚度（systolicinterventricular septal thickness,IVS;s）,舒张期室间隔厚度（diastolic interventricular septal thickness,IVS;d）,左室质量指数（LV Mass）及校正后的左室质量指数（LV Mass Corrected）等,还原型谷胱甘肽（glutathione,GSH）和氧化型谷胱甘肽（glutathione disulfide,GSSG）检测试剂盒检测心肌组织中GSH的含量,并计算大鼠的存活率。结果：与BC组相比,NS组左室后壁厚度明显变薄,室间隔厚度显著减小,GSH含量明显减少,存活率明显下降,左室质量指数及校正后的左室质量指数明显增大,差异均具有显著统计学意义（P〈0.05）;NAC组左室后壁厚度、室间隔厚度等未见明显减小,左室质量指数及校正后的左室质量指数未见明显增大GSH含量未见明显降低,差异均不具有统计学意义（P〈0.05）,但存活率明显下降,差异具有统计学意义（P〈0.05）;与NS组相比,NAC组左室后壁厚度增厚,室间隔厚度显著提高,左室质量指数及校正后的左室质量指数明显减小,GSH含量明显增高,差异均具有统计学意义（P〈0.05）,但存活率无明显统计学差异（P〉0.05）。结论：NAC能改善大鼠心肌梗死后心室结构的重塑,可能与抑制氧化应激,增加GSH的含量有关,但其对心肌梗死后大鼠的存活率无明显影响。

Research on Improvement of Left Ventricular Structural Remodeling after Myocardial Infarction in Rats by N-Acetylcysteine

Objective： To investigate the potential effects and possible mechanisms ofN-acetylcysteine （NAC） on left ventricular structural remodeling after myocardial infarction in rats. Methods： Total 96 Sprague-Dawley were randomly divided into blank control group（BC group, n=6）, the rest 90 underwent myocardial infarction model were randomly divided into NAC group（n=34） and NS group （n=32） 24 h after survival. Rats in NAC group were intraperitoneal injected with NAC （0.2 mg. kg^-1. 2d^-1） for 4 weeks, while rats in NS group were given the same volume of normal saline as control After 4 weeks, the systolic left ventricular posterior wall thickness（LVPW; s）, the diastolic left ventricular posterior wall thickness （LVPW;d）, systolic Interventricular septal thickness （1VS;s）, diastolic Interventricular septal thickness（IVS;d）, LV Mass Corrected and LV Mass were measured by Ultrasound Cardiography, the level of GSH was measured by GSH/GSSG kit, the morality was also calculated. Results： In comparison with BC group, GSH level in NS group was significantly lower（P〈0.05）, LVPW; d, LVPW; s, IVS; d, IVS; s, LV Mass Corrected and LV Mass appeared much thinner（P〈0.05）, the survival rate decreased in both NS group and NAC group. In comparison with NS group, GSH level was significantly higher in NAC group（P〈0.05）, LVPW;d, IVS;d, IVS;s, LV Mass Corrected and LV Mass appear much thicker（P〈0.05）, but no significant difference was observed on the survival rate （P〉0.05）. Conclusions： NAC was capable to inhibit the left ventricle remodeling from myocardial infarction in rats at least in part through up-regulation of GSH, but it didn＇t improved the survival after myocardial infarction.