GLUT4-containing vesicles in rat adipocytes as a tissue-specific recycling compartment

In rat adipocytes under basal conditions, GLUT4 is found in homogeneous intracellular vesicles with a sedimentation coefficient of 100–120 S and a buoyant density of 1·12 g/cm³. These structures recycle between the plasma membrane and an intracellular pool(s) in such a way that in any given moment of time only about 2–5% of these vesicles are fused with the plasma membrane. Insulin dramatically shifts the equilibrium towards the plasma membrane