Progressive defect of insulin action on glycogen synthase in obesity and diabetes.

The purpose of the present work was to have a closer view on the changes in the regulation of glycogen synthase (GS) activity by insulin in relationship with the impairment of nonoxidative glucose disposal in human obesity. Obese patients with normal glucose tolerance (12), impaired glucose tolerance (11), diabetes (10), and lean control subjects (15) participated to the study. A euglycemic, hyperinsulinemic clamp was performed and associated with indirect calorimetry.