中文摘要：

目的：观察马拉松运动后不同时相人体外周血细胞DNA的损伤效应及血浆中SOD、GSH和MDA活性的变化，探讨大强度耐力运动引起人体血细胞DNA损伤的机制。方法：选取7名参加2007年北京国际马拉松赛的健康男运动员，分别在运动前一天（CG）、运动后2h（2h）、24h（24h）和48h（48h）采血抗凝，用单细胞凝胶电泳（SCGE）技术检测人体外周血细胞DNA损伤，并测定血浆中超氧化物歧化酶（SOD）活性、谷胱甘肽（GSH）和丙二醛（MDA）含量。结果：运动后2h和24hDNA损伤程度显著高于安静水平，2h显著高于24h；48h基本恢复至安静水平。2h血浆中SOD活性、GSH和MDA含量均较安静水平显著升高；24hSOD和MDA仍显著高于安静水平，而GSH水平则无显著差异；48hSOD、GSH和MDA均较安静水平无显著差异。结论：马拉松运动对人体外周咀细胞的DNA损伤具有明显的诱发作用，且存在一定的时序性特征。运动性氧应激是导致人体外周血细胞DNA损伤的原因之一。

英文摘要：

Objective： to investigate the DNA damage and the level of anti-oxidative status on human peripheral blood cell in different, time ＇after Marathon running, and discuss the mechanism of DNA damage induced by endurance exercise. Method： We select seven healthy men athletes, who participated in International Marathon Match in 2007. The subjects are required to have a test at the time of twenty-four hours＇ pre-exereise, also 2 hours, 24 hours and 48 hours after exercise. We investigate the DNA damage on htmran peripheral blood cell by using the single cell gel electrophoresis （SCGE） and detected the level of SOD, GSH and MDA in serum. Results： The results have shown that the DNA damage on peripheral blood cell significantly increased at 2h and 24h after exercise and the 2h is significant higher than the 24h. It reduces to the level of pre-exercise after 48 hours. The activity of SOD and the content of GSH and MDA in serum increase significantly at 2h compared with the pre-exereise, and SOD activity and MDA content are still significant higher than the pre-exercise. The changes of the indexes in serum at 48h have no significant difference compared with the pre-exereise. Conclusions： The Marathon running can result the DNA damage in human peripheral blood cell and there exists a certain time sequence. Exercise-induced oxidative stress may be one of the DNA damage mechanisms.