罗格列酮及饮食干预对胰岛素抵抗大鼠骨骼肌GLUT4转位的影响

目的　探讨罗格列酮对胰岛素抵抗大鼠骨骼肌细胞葡萄糖转运蛋白 4(GLUT4)转位的影响。方法　利用高脂饲料喂养 ,使Sprague -Dawley(SD)大鼠产生胰岛素抵抗 ,用罗格列酮及饮食干预治疗 4周后 ,取骨骼肌组织 ,应用Western -bloting印迹法分析骨骼细胞膜GLUT4表达量。结果　在胰岛素刺激下 ,胰岛素抵抗大鼠骨骼肌细胞膜GLUT4表达较正常大鼠下降 5 2 72 %(P <0 0 0 1) ,罗格列酮及饮食干预组 ,细胞膜GLUT4表达较未干预胰岛素抵抗大鼠分别增加 49 5 3 %、5 0 3 4%(P <0 0 0 1)。结论　罗格列酮可促进胰岛素刺激的GLUT4转位 ,从而改善高脂喂养所引起的骨骼肌组织胰岛素抵抗

Effects of Rosiglitazone on GLUT4 Protein Translocation in Skeletal Muscle of Insulin Resistance Rat

Objective To investigate effects of rosiglitazone on glucose transport-4(GLUT4) protein translocation in skeletal muscle of insulin resistance rats. Methods 38 male sprague dawley rats were randomized to received high fat or standard chow diet for 8 weeks, feeding high-fat diet to induce insulin resistance in skeletal muscle of rats. 25 high-fat-fed rats were randomly treated with rosiglitazone(1mg/kg), standard chow diet, or placebo(high-fat diet) for 4 weeks. Plasma concentrations of glucose and insulin, weight and viscero-fat in all rats were measured. The GLUT4 level in the cell membrane of isolated rats skeletal muscle was detected by western blotting analysis. Results Insulin-stimulated translocation of GLUT4 to the plasma membrane in skeletal muscles of high fat-fed rats was significantly lower than that of standard chow-fed rats(52 72%,P<0 001). But the defects of GLUT4 translocation in skeletal muscle of high-fat-fed rats were fully prevented by rosiglitazone or standard chow diet. Conclusion Rosiglitazone is an insulin-sensitizing agent that appears to prevent insulin resistance in skeletal muscle of high-fat-fed rats by selectively improving GLUT4 translocation to the cell membrane.