递增负荷有氧运动对老龄雌性大鼠心肌抗氧化酶及心肌线粒体超微结构的影响

目的：探讨长时间递增负荷有氧运动对老龄雌性大鼠心肌抗氧化酶活性和心肌线粒体超微结构的影响。方法：健康雌性18月龄SD大鼠30只,随机分为两组：老龄运动组和老龄对照组,每组15只;另安排15只3月龄SD大鼠作为年青对照组。采用20周递增负荷跑台运动建立中老年大鼠有氧运动模型,运动方案结束后取心肌组织,检测心肌组织SOD、GSH-Px、CAT活性和MDA含量,并采用透射电镜观察大鼠心肌组织线粒体超微结构的变化。结果：（1）递增有氧运动能显著提高心肌SOD、GSH-Px活性,显著降低心肌MDA含量,但CAT活性未见显著提高;（2）递增有氧运动能改善心肌线粒体因衰老导致的形态改变,延缓心肌线粒体退行性变化。结论：（1）递增有氧运动能提高老龄大鼠心肌抗氧化酶活性,降低老龄运动组大鼠心肌MDA含量,保护心肌组织因衰老而导致的自由基的损害;（2）长期递增有氧运动能改善老龄大鼠心肌线粒体结构,保护线粒体膜和嵴的完整性,延缓心肌线粒体因衰老而导致的退行性变化。

Effect of Regular Aerobic Exercise on Anti-oxidation Enzyme and Morphology of Mitochondria in Aged Female Rats

Objective：To explore the effect of long-term progressive aerobic exercise on activity of myocardial antioxidant enzyme and the mitochondria morphology in aged female rats.Materials and methods：30 18-months-old female SD rats were randomly divided into aged control group and aged exercise group,and 15 3-months-old female SD rats were as young control group.20 weeks progressive aerobic treadmill exercise was applied to establish animal model of aerobic exercise.Activity of SOD,GSH-Px,CAT and content of MDA in myocardial tissue were tested,and mitochondria was observed using transmission electron microscope.Results：Progressive aerobic exercise can significantly increase myocardial SOD,GSH-Px activity,significantly decrease myocardial MDA content.Meanwhile regular progressive aerobic exercise can delay degenerative change of structure in myocardial mitochondria caused by aging.Conclusion：（1） Regular aerobic exercise can improve myocardial antioxidant enzyme activity,decrease MDA content,protect myocardial tissue caused by aging free radical damage,and delay senescence in cardiac muscle of old rats,（2） Long-term regular aerobic exercise can improves structure of myocardial mitochondria in aged rats,protect the mitochondrial membrane and the integrity of the mitochondrialcristae,delay the degenerative change of mitochondria by aging.