PREFERENTIAL ALTERATION OF OXIDATIVE RELATIVE TO TOTAL GLYCOLYSIS IN PANCREATIC-ISLETS OF 2 RAT MODELS OF INHERITED OR ACQUIRED TYPE-2 (NON-INSULIN-DEPENDENT) DIABETES-MELLITUS

In islets from both adult rats injected with streptozotocin during the neonatal period and spontaneously diabetic rats obtained by repeated selective breedings (GK rats), the ratio between D-[3, 4-C-14]glucose oxidation and D-[5-H-3]glucose conversion to (HOH)-H-3 was 25 % lower than in islets from control rats, indicating an impaired contribution of oxidative to total glycolysis. No primary defect in the Krebs cycle was found in the islets of diabetic rats, as judged from the ratio between either D-[2-C-14]glucose or D-[6-C-14]glucose and D-[3, 4-C-14]glucose oxidation. Therefore, we propose that a preferential alteration of oxidative glycolysis in the pancreatic beta cell may contribute to the impairment of glucose-induced insulin release not only in a cytotoxic but also in a spontaneous model of non-insulin-dependent diabetes mellitus.