低氧暴露对运动性贫血大鼠抗氧化能力的影响

Influence of intermittent hypoxic exposure on the antioxidation in rats of sports anemia

目的:观察低氧暴露对运动性贫血大鼠某些抗氧化酶的影响,探讨低氧条件下抗氧化系统的反应是否有利于改善运动性贫血。方法:实验于2005-07/09在广东省高等学校运动生物化学教学重点实验室完成。选择6周龄健康雄性SD大鼠40只,均为运动性贫血动物模型,大鼠适应环境1周后采用6周递增负荷跑台运动方式建立。按随机数字表法分为1h低氧暴露组、2h低氧暴露组和间歇性低氧暴露组、常氧恢复组,每组10只。采用人工常压低氧环境,低氧浓度控制在14.5%左右,按分组每天在常压低氧舱进行1,2h和间歇性低氧暴露(低氧暴露1h,中间间歇3h,再低氧暴露1h),其余时间在舱外常氧中自由活动,每周6d,持续3周。常氧恢复组大鼠在常氧中自由活动。3周后测试运动性贫血大鼠血清丙二醛含量、超氧化物歧化酶活性和血浆过氧化氢酶、谷胱甘肽过氧化酶活性。结果:纳入动物40只,均进入结果分析。①低氧暴露3周后1h低氧暴露组、2h低氧暴露组、间歇性低氧暴露组血清丙二醛含量均显著低于常氧恢复组[分别为(2.62±0.16),(2.60±0.22),(2.55±0.06),(3.36±0.34)μmol/L,P<0.05]。②低氧暴露3周后血清超氧化物歧化酶和血浆谷胱甘肽过氧化酶、过氧化氢酶活性均高于常氧恢复组,2h低氧暴露组与常氧恢复组比较差异有显著性意义[分别为(4239.68±169.53),(3190.30±339.40)μkat/L;(20622.46±2002.07),(15556.44±607.79)μkat/L;(50.01±6.67),(35.17±4.50)μkat/L,P<0.05]。③各低氧暴露组间除2h低氧暴露组血清超氧化物歧化酶活性显著高于1h低氧暴露组外[分别为(4239.68±169.53),(2126.41±161.20)μkat/L,P<0.05],其他指标组间差异无显著性意义(P>0.05)。结论:低氧暴露可提高运动性贫血大鼠机体的抗氧化能力,有利于促进运动性贫血的恢复。

AIM： To investigate the effects of hypoxic exposure on the activities of some antioxidant enzymes in rats with sports anemia and explore if the changes of the antioxidant system elicited by hypoxic exposure can help to improve sports anemia. ＂METHODS： This experiment was conducted from July to September 2005 at the Key Laboratory of Exercise Biochemistry in Guangdong College. Forty male healthy SD rats （6 weeks old） were chosen to carry out the progressive load treadmill exercise for 6 weeks. After the establishment of the sports anemia model, all the rats were divided at random： normoxia recovery group, 1-hour hypoxic exposure group, 2-hour hypoxic exposure group and intermittent hypoxic exposure group （1-hour hypoxic exposure, 3-hour interval and then 1-hour hypoxic exposure）, with 10 rats in each. According to the grouping, the hypoxic exposure groups practiced the training protocol in the normobaric hypoxic cabin （artificial normobedc hypoxia at 14.5% oxygen content） for 1 hour, 2 hours and （1＋1） hours per day, respectively, 6 days a week for 3 weeks successively, while the normoxia group conducted free-running in normal pressure. The serum malondialdehyde （MDA） concentration, superoxide dismutase （SOD）, glutathione peroxidase （GSH-Px） and catalase （CAT） activities of rats with sports anemia were measured after 3 weeks. RESULTS： Totally 40 rats were involved in the result analysis.①After three weeks＇ hypoxic exposure, the concentrations of MDA in hypoxic exposure groups ware significantly lower than that in normoxia recovery group [（2.62±0.16）, （2.60± 0.22）, （2.55±0.06）, （3.36±0.34） μmol/L, P 〈 0.05].②After three weeks＇ hypoxic exposure, SOD, GSH-Px and CAT activity were higher in hypoxic exposure groups, but only between 2-hour hypoxic exposure group and normoxia recovery group there was a significant difference [（4 239.68±169.53）, （3 190.30±339.40） μkat/L; （20 622.46±2 002.07）, （15 556.44±607.79） μkat/L; （50.01 ±6.67）, （35.17±4.50） μkat/L, P 〈 0.05].③Except that the level of SOD in 2-hour hypoxic exposure group was higher than that in 1.hour hypoxic exposure group [（4 239.68±169.53）, （2 126.41＋161.20） μkat/L, P 〈 0.05], there were no significant differences for the other indexes among the hypoxic exposure groups compared with each other （P 〉 0.05）. CONCLUSION： Hypoxic exposure is effective on improving the antioxidant capacity in the rats with sports anemia. and it can promote the treatment of sports anemia.