热预处理对急性运动大鼠股四头肌抗氧化能力的影响

Effect of hyperthermic treatment on antioxidant ability in rat quadriceps femoryafteries of acute exercise

目的:通过观察热预处理后大鼠急性运动股四头肌热休克蛋白70(HSP70)、超氧化物歧化酶(SOD)、丙二醛(MDA)的变化,并和室温进行相同负荷运动时各项指标进行比较,探讨HSP70对急性运动大鼠股四头肌自由基代谢的影响。方法:三月龄雄性SD大鼠随机分为室温安静组、室温运动组、热处理安静组、热处理运动组。热处理组进行热暴露处理室温恢复24 h后,运动组大鼠进行一次急性运动,运动后3 h进行取样,对股四头肌HSP70的表达、SOD活性和MDA含量进行测试。结果:1)热处理安静组HSP70(465.6±19.3)含量明显高于室温安静组(312.8±58.2)(P(0.05),热处理运动组HSP70(542.6±12.1)含量明显高于室温运动组(411.9±31.1)(P(0.05);2)热处理安静组SOD活性高于室温安静组,但不具有显著性差异(P>0.05),热处理运动组SOD活性显著高于室温运动组(P(0.05);3)室温组和热处理安静组MDA含量无显著性差异(P>0.05),热处理运动组MDA含量与室温运动组比较显著降低(P(0.05)。以上结果表明本实验热处理方案,可以明显提高股四头肌HSP70的表达,HSP70的高表达可增加运动时SOD活性,减少MDA的含量。提示HSP70可能会提高机体的抗氧化能力,对维持运动应激时机体氧化和抗氧化平衡具有一定作用。

The purpose of this study was to test the hyperthermic treatment on free radical metabolism in rat quadriceps femories by comparing heat shock protein70 （HSP70）, superoxide dismutase （SOD）, Malonldehyde （MDA） during the same condition after an acute exercise. Adult （3 months old ） SD rats were divided into four groups： normothermic sedentary （NS） , normothermic exercise （NE）, heat stress sedentary （ HS）, heat stress exercise （HE）. The rats were heated until the rectal temperature reached 42℃ for 15 rain. Then the rats of Heat Sed were at rest under the normal temperature for 24h. Norm sed and Heat Sed were killed immediately, Norm Exe and Heat Exe ran on a treadmill for one hour . The rats were killed quadriceps femories were sampled to analyze HSP70 ,SOD ,MDA. The results were as followsl ） hsp70 content in HS（465. 6 ±19.3 ） were significantly higher than those in NS （ 312.8 ± 58.2） （ P 〈 0.05 ）, The similar result took place between HE and NE（P 〈 0.05） ;（2）SOD activity was higher in HS than that in NS （P〉0.05） ,but SOD activity in HE was significantly higher than in NE （ P 〈 0.05 ）. 3 ） compared with HE , MDA content was higher significantly in NE（P 〈 0.05）. Theses finds demonstrated HSP70 was probably involved in eliminating free radicals and improving antioxidative ability when exercise stress.