Objective: To probe into the effects of GLUT4 and IL-6 on the development of insulin resistance(IR) inhibited by exercise. Methods: Rats were fed by 8 weeks high-fat diets to develop IR, and glucose infusion rates (GIR) were determined by hyperinsulinemic-euglycemic clamping to confirm the development of IR. 8 weeks treadmill exercise (the speed and duration time in the first week were respectively 16m/min and 50min, and speed increased 1m/min and duration time increased 5min every week following it) and/or IL-6shRNA plasmid injection (rats received 4time IL-6shRNA injection via the tail vein every two weeks) were adopted. The indexes of serum IL-6, fasting blood glucose, fasting serum insulin, GIR, IL-6 gene expression levels and p-p38 invarious tissues were determined. Results: Rats fed by 8 weeks high-fat diets were developed IR and the IL-6mRNA levels of IL-6shRNA injection groups were significantly lower than those of control group(P<0.05,or P<0.01). The development of IR in exercise rats significantly decreased, however, compared with that, the GIR of exercise rats injected by IL-6shRNA was lower (P<0.05,or P<0.01). The IL-6 and GLUT4mRNAlevels in the high-fat diets rats significantly increased(P<0.01), compared with those of control rat, and those in the high-fat diets exercised rats were more high(P<0.01). However, the IL-6 and GLUT4 mRNA levels in high-fat diets and high-fat diets exercised IL-6shRNA injected groups significantly decreased(P<0.01), compared with that of respective saline injected groups. Conclusions: High-fat diets and exercise led to increase of IL-6 and GLUT4 gene expression in the skeletal muscles. The inhibition of insulin resistance development by exercise was related with IL-6 promoting the gene expression of GLUT4.
