NaAsO2中毒对大鼠左心收缩功能及心脏毒性的影响

Effects of NaAsO2 Poisoning on Left Ventricular Systolic Function and Cardiotoxicity in Rats

目的探讨砷中毒对大鼠左心室收缩功能的影响及心脏的毒性作用。材料与方法选取12周龄SD大鼠48只,体重(220±20)g。采用完全随机法分为4组:正常对照组(自由饮水)以及低、中、高剂量NaAsO2染毒组(NaAsO2剂量分别为5mg/kg、10mg/kg、20mg/kg),每组12只。建立NaAsO2染毒模型12周前后,采用超声心动图检测大鼠心脏左心室短轴缩短率(LVFS)及左心室射血分数(LVEF)等。然后处死大鼠,取左心室心肌组织,经Masson染色后观察大鼠心肌胶原纤维的分布情况,测定心肌细胞中超氧化物歧化酶(SOD)活力?还原型谷胱甘肽(GSH)和丙二醛(MDA)水平。结果NaAsO2染毒组大鼠LVEF及LVFS均低于正常对照组[LVEF:(69.89±2.35)%比(83.92±2.39)%;LVFS:(38.79±1.64)%比(49.28±1.71)%,(P均<0.05)]。Masson染色显示,NaAsO2染毒组大鼠心肌细胞明显肥大,心肌间隙中的胶原纤维明显增多。与对照组比较,不同剂量NaAsO2染毒组大鼠心肌组织组织中的SOD活力及GSH水平较低,而MDA水平较高,差异均有统计学意义(P<0.05)。结论NaAsO2中毒可能导致大鼠左心功能及心肌纤维形态结构损伤。

Purpose To investigate the effects of arsenic poisoning on left ventricular systolic function and the toxic effects of the heart.Materials and Methods Forty-eight SD rats of 12 weeks old,with weight of (220±20) g,were selected and randomized into 4 groups:normal control group (free drinking water) and low,medium and high dose NaAsO2 exposure groups (NaAsO2 doses were 5 mg/kg,10 mg/kg and 20 mg/kg,respectively),with 12 rats in each group.The left ventricular fraction shortening (LVFS) and left ventricular ejection fraction (LVEF) of the rat heart were detected by echocardiography 12 weeks before and after the NaAsO2 exposure model was established.The rats were executed and the left ventricle myocardium was taken.The distribution of myocardial collagen fibers was observed by Masson staining.The superoxide dismutase (SOD) activity,reduced glutathione (GSH) and malondialdehyde (MDA) levels in cardiomyocytes were determined.Results The LVEF and LVFS in the NaAsO2 exposure groups were lower than those of the normal control group[LVEF:(69.89±2.35)% vs.(83.92±2.39)%;LVFS:(38.79±1.64)% vs.(49.28±1.71)%,P<0.05].Masson staining showed that the cardiomyocytes in the NaAsO2 exposure groups were significantly hypertrophied,and the collagen fibers in the myocardial gap were significantly increased.Compared with the control group,the SOD activity and GSH level in the myocardial tissue of the rats exposed to different doses of NaAsO2 exposure groups were lower,the level of MDA was higher,and the difference was statistically significant (P<0.05).Conclusion NaAsO2 poisoning may cause damage to left ventricular function and myocardial fiber morphology in rats.