Objective:To observe effects of Huanglian Jiedu Decoction on expression of insulin receptor substrate 1（IRS-1）and the level of tyrosine phosphorylation in skeletal muscles to explore the molecular mechanism in improving insulin resistance.Methods:Wistar system insulin resistance model rats were developed with injection of small dose of streptozotocin into the caudal vein plus feeding by forage with high sugar and high lipids

and they were treated with Huanglian Jiedu Decoction for 10 weeks.Then blood sugar and serum insulin level were determined

and the changes of IRS-1 protein expression and tyrosine phosphorylation level in the skeletal muscles of the rat with insulin resistence after treatment of Huanglian Jiedu Decoction were detected with immuno- precipitation and Western Blot methods.Results:After treatment with Huanlian Jiedu Decoction

IRS-1 expression and IRS-1 tyrosine phosphorylation level in the muscular tissue increased as compared with those of the model group.Conclusion Huanglian Jiedu Decoction improves IRS-1 protein expression and tyrosine phosphorylation level in the skeletal muscle tissue of the rats with insulin resistance

which is possibly one of the mechanisms of decreasing blood sugar and improving sensitivity of insulin in tissues.