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Muscle Cell Diagram

Muscle Cell Diagram

Shulman and colleagues propose that fatty acids block glucose movement from the bloodstream into the muscles. By activating an enzyme called PKC0, the fatty acids set off a cascade that causes defects in activation of insulin receptor substrates (IRS-1 and IRS-2). This, in turn, blocks PI 3-kinase, an enzyme that stimulates GLUT4 to transport glucose into the muscle cell.