摘要
目的:为探讨肥胖和运动减肥的机制,观察长期的有氧耐力训练对大鼠脂代谢、血清胰岛素和骨骼肌胰岛素受体mRNA表达的影响,将100只SD大鼠进行高脂膳食喂养8周,按体重分为3大组,即肥胖、中间、肥胖抵抗组,三组间的体重极显著差异(P<0.01)。将各组分为对照组和运动组,共6组。各组继续进行高脂膳食,运动组进行7周的游泳训练,观察体重、体脂、血清胰岛素和骨骼肌胰岛素受体的mRNA的表达变化。结果显示:1)肥胖组体重、脂肪量、体脂率显著高于中间组(P<0.01);抵抗组体重、脂肪量显著低于中间组(P<0.05)。肥胖运动组、中间运动组体重、脂肪量、体脂率分别显著低于自身对照组(P<0.01)。2)肥胖组胰岛素显著高于中间组与抵抗组(P<0.01)。3)肥胖运动组血清GLU和胰岛素显著低于肥胖组(P<0.01、P<0.05),而肌糖原显著升高(P<0.05)。4)肥胖组胰岛素受体mRNA表达显著低于中间组和抵抗组(P<0.05)。肥胖运动组胰岛素受体mRNA表达有下降趋势但无显著性变化。结论:1)相同品系大鼠对高脂膳食的敏感程度存在很大差异,有氧耐力运动对肥胖和中间体重大鼠有很好的减肥作用,但对肥胖抵抗组没有降体脂的作用。2)长期的高脂膳食引起肥胖大鼠骨骼肌胰岛素敏感性下降,出现了外周性胰岛素抵抗。3)有氧耐力训练能有效降低高脂膳食诱导的肥胖大鼠体脂,降低血浆胰岛素水平,增加肌糖原含量,但未出现骨骼肌胰岛素受体mRNA表达增加,推测可能与胰岛素受体mRNA表达时序性有关。
Objective：The purpose of this study was to investigate the effects of endurance exercise training on fat metabolism and plasma insulin and insulin receptor mRNA expression in skeletal muscle of rats. Methods： 100 Sprague-dawley （SD） rats were given ad libitum access to a high-fat diet （HFD） for 8 weeks ,and then were randomly allocated to one of the following groups according to body weight：obese, obese exercise training, mid, mid exercise training, obese-resistance, obese-resistance exercise training. There were significant differences in body weight between the obese, mid, obese-resistance rats （ P 〈 0.01 ）. During the subsequent 7-week experimental period, rats continued to eat a high-fat diet and the rats in exercise protocols were submitted to swimming exercise for 7 weeks. We determined the effects of exercise training on body weight,body fat, plasma insulin and muscle insulin receptor mRNA expression in high-fat-fed rats. Results：Obese group had a greater body weight, body fat and percentage of body fat then mid group（ P 〈 0.01 ）. In contrast, obese-resistance group had lower body weight and body fat than mid group （ P 〈 0.05 ）. Endurance exercise training reduced body weight,body fat,percentage of body fat in obese and mid exercise training rats. Rats with obese group had higher plasma insulin than mid and obese-resistance rats（ P 〈0.01 ）. Compared with the obese group,Plasma glucose and insulin were decreased （P 〈0.01 ,P 〈 0.05 ）;but muscle glycogen content was elevated in obese exercise training group（ P 〈 0.05 ）. Obese rats had lower muscle insulin receptor mRNA expression than mid and obese-resistance rats （P 〈 0.05 ）. Muscle in- sulin receptor mRNA expression only tended to decrease with exercise training in obese exercise training group. Conclusion：There are great difference in sensitivity to high-fat diet between the same strain rats. After endurance exercise training ,body mass decreased significantly in fat and mid-weight rats but not in obese-resistance rats. Long-term high-fat feeding resulted in decreased muscle insulin sensitivity in obese rats and induced insulin resistance in peripheral tissues. Aerobic endurance exercise reduced the body fat and plasma insulin in obese rats which were induced by high-fat diet; and a increase in muscle glycogen content. However,endurance exercise did not appear to improve the mRNA expression of muscle insulin receptor which may be associated with the timing of mRNA expression of insulin receptor.
出处
《沈阳体育学院学报》
北大核心
2010年第5期53-56,60,共5页
Journal of Shenyang Sport University
基金
辽宁省高等学校科学研究项目
编号为2008707
关键词
肥胖
高脂膳食
胰岛素
胰岛素受体
有氧运动
obesity
high-fat diet
insulin
insulin receptor
aerobic endurance exercise
