Enhanced Insulin-Stimulated Activation of Phosphatidylinositol 3-Kinase in the Liver of High-Fat-Fed Rats

摘要

Insulin receptor substrate (IRS)-1 and IRS-2, which mediated phosphatidylinositol (PI) 3-kinase activation, play essential roles in insulin-induced translocation of GLUT4 and in glycogen synthesis. In this study, we Investigated the process of PI 3-kinase activation via Binding with IRS-1 and -2 in liver, muscle, and fat of High-fat-fed rats, a model of insulin-resistant diabetes. In the liver of high-fat-fed rats, insulin increased the PI 3-kinase regulatory subunit p85a and the PI 3-kinase activities associated with IRS-1 3.6- and 2.4-fold, and with IRS-2, 4.7- and 3.0-fold, respectively, compared with those in control rats.