耐力运动对大鼠骨骼肌ERK1/2活性的影响

目的:探讨耐力运动对大鼠骨骼肌蛋白总量(t-ERK1/2)及磷酸化ERK1/2(p-ERK1/2)及ERK2mRMA表达的影响。方法:SD大鼠随机分为对照组和运动组。运动组分为1h/d和1.5h/d组,共7周,运动结束后24h和48h取材,测定葡萄糖和胰岛素浓度;Westernblot法检测骨骼肌t-ERK1/2、p-ERK1/2蛋白表达;RT-PCR法分析ERK2mRNA表达。结果:与对照组比较,运动组胰岛素浓度降低;各运动组p-ERK1/2升高;1.5h/d-24h和-48h组t-ERK1/2增高;1h/d-24h组与1.5h/d-24h和-48hERK2mRNA表达增高。结论:耐力运动可能通过增加ERK1/2活性,提高大鼠骨骼肌对胰岛素的敏感性。

Effects of endurance exercise on ERK1/2 phosphorylation and expression in skeletal muscle of rats

Aim:To investigate the effects of exercise on phosphorylated and total ERK1/2,and mRNA of ERK2.Methods:Male rats were randomly divided into control and trained groups.The trained rats were submitted to 1 h or 1.5 h of exercise daily and had a fragment of their excised gastroenemius muscle,24 h or 48 h after the last training session.The train lasted for 7 weeks.The changes in the expressions of ERK1/2 and p-ERK1/2 were determined by Western blotting.The expression of ERK2 mRNA was determined by RT-PCR.Results:Exercise led to a marked increase in p-ERK1/2 of trained groups as compared with controls,and increased ERK1/2 protein expression of training 1.5 h/d,24 h and 48 h after the last training session.ERK2 mRNA was increased by exercise 1 h/d,24 h and exercise 1.5 h/d,24 h and 48 h after the last training session.Glucose tolerance test found that blood insulin concentration was decreased with exercise training.Conclusion:Endurance exercise could increase muscle responsiveness to insulin by improving the total ERK1/2 and p-ERK1/2,ERK2 mRNA expression.