不同负荷游泳训练对大鼠骨骼肌HSP70应答及其脂质过氧化的影响

Study on the Changes of Rats Skeletal Muscle Hsp70 Expression and Lipox in Different Load Swimming Training

目的:研究不同负荷游泳训练对于骨骼肌HSP70应答及其脂质过氧化水平的影响,探讨HSP70保护细胞结构的机制;方法:40只雄性SD大鼠随机分成安静对照组(CG),无负重游泳组(FG),负重5%体重游泳组(5%G),负重10%体重游泳组(10%G)和负重15%体重游泳组(15%G)。负重组游泳每游6 min间歇2 min,每天连续进行5组。5%G组大鼠尾根部悬挂自体重5%重物游泳;10%G第1周负5%自体重训练,后3用负重10%;15%G第1周负5%自体重,第2周负重10%,第3、4周负重15%。FG持续游90 min。经过4周的训练,所有大鼠处死后测试大腿股四头肌中SOD、MDA及HSP70含量;结果:1)负重游泳训练使大鼠骨骼肌HSP70水平升高,而且负荷越大,升高就越明显,并且有一定的平台期,但15%G组大鼠骨骼肌HSP70水平陡然下降(P<0.01);2)负重游泳训练造成骨骼肌MDA水平的显著性提高(P<0.01),且依赖负荷的诱导,而对SOD影响并不明显;3)骨骼肌HSP70水平和脂质过氧化程度变化趋势的负相关程度随着训练负荷的增加而增加;结论:骨骼肌中HSP70含量随运动应激强度的增加而增加,并在平台时期,把脂质过氧化增加过程控制在相对和缓的状态,当训练负荷突破平台期时,就会出现HSP70含量的急剧下降和脂质过氧化水平的突增。

The purpose of the test was to research changes of rat skeletal muscle Hsp70 expression and lipox in different load swimming training. Forty male Sprague-Dawley （SD） rats were randomly assigned to control group （CO） and exercise group which was further divided into swimming wkhout load group（FG）, swimming with loading 5 % body weight group （ 5 % G）, swimming with loading 10% BW group（5%G）and swimming with loading 15% BW group （15 %G）. The time that the rats of FG swam is 90 minutes. After four-weeks exercise, the content of SOD, MDA and HSP70 of rat are tested. The result shows, 1）The rats＇ skeletal muscle Hsp70 increased. The improvement of Hsp70 level depends on the exercise intensity, and there was a platform stage in the improvement of Hsp70 level. But the 15 ;G rats skeletal muscle Hsp70 decreased significantly（P〈0.01）. 2）Compared with control group rats, skeletal muscle SOD 1 rats has no change obviously, while skeletal muscle MDA level of 10 ; G and 15 %G rats increased significantly compared with other groups （P〈0. 01）. 3）There was a negative correlation between skeletal muscle Hsp70 express and lipox, which increased when exercise intensity increased. It concludes that the skeletal muscle Hsp70 express increases with sports stress intensity increases, and control the lipox degree in a meek condition before the end of platform stage. The Hsp70 express decreases and lipox increases significantly when exercise intensity exceeds the limit intensity of platform stage.