【摘要】 目的探讨N-乙酰半胱氨酸(N-acetylcysteine,NAC)对过度训练大鼠心肌过氧化损伤的保护作用。方法 36只雄性Wistar大鼠随机均分为3组:对照组(C组)、过度训练组(O组)和过度训练+NAC干预组(N组)。采用7周反复力竭游泳应激建立过度训练致心肌损伤动物模型,分组处理后测定大鼠心肌各种超氧化物岐化酶(superoxide dismutase,SOD)活性、丙二醛(malondialdehyde,MDA)含量和血清肌酸激酶MB同工酶(creatine kinase MB,CKMB)及心肌肌钙蛋白I(troponin I type 3,TNNI3)的含量;透射电镜观察心肌组织的超微结构。结果与C组比较,O组血清CK-MB、TNNI3水平明显升高(P<0.01);经NAC干预后,与O组比较,N组血清CK-MB(11.998±0.634)pg/ml、TNNI3(128.265±11.489)pg/ml水平明显下降(P<0.01),心肌组织T-SOD、Mn-SOD及CuZn-SOD活性和MDA含量都较O组明显改善(P<0.01)。电镜下,O组心肌细胞核明显肿胀,并且大部分心肌肌丝溶解,经NAC干预后,N组心肌超微结构损伤明显轻于O组。结论过度训练可引起心肌损伤,NAC能够通过其抗氧化作用来减轻大鼠心肌过度训练所致的过氧化损伤。更多还原

【Abstract】 Objective To study the protective effect of N-acetylcysteine(NAC)on myocardial injury of peroxidization in overtraining rats.Methods Thirty-six male Wistar rats were randomly divided into control group(group C,n=12),overtraining group(group O,n=12)and overtraining with NAC administration group(group N,n=12)).The animal model of overtraining-induced myocardial injury was developed by seven weeks repeated exhaustive swimming stress.The activity of various superoxide(SOD),the content of malondialdehyde(MDA),creatine kinase MB(CK-MB)and troponin I type 3(TNNI3)were measured after the last swimming training.Transmission electron microscope(TEM)was used to analyze the structure of myocardium.Results Serum CK-MB and TNNI3 contents were significantly increased in group O than those in group C[CK-MB:(19.343±0.944)pg/ml vs.(8.866±0.950)pg/ml,TNNI3:(198.107±12.060)pg/ml vs.(84.854±11.574)pg/ml,P<0.01].Serum CK-MB(11.998±0.634)pg/ml and TNNI3(128.265±11.489)pg/ml were significantly decreased,and T-SOD,Mn-SOD and CuZn-SOD activities and MDA contents were significantly improved in group N compared with those in group O(P<0.01).TEM observation indicated that,there were obvious myocardial cell nucleus swelling,and most myofilaments dissolution in group O.The myocardial microstructures were less damaged in group N.Conclusion Overtraining can induce myocardial damage.NAC can prevent myocardial injury of peroxidization induced by overtraining via its antioxidation effect.更多还原