Depolarization in the absence of exogenous nutrients inhibits the metabolic amplification by glucose but not KIC

Background and aims: Metabolic amplification of insulin secretion is the signaling process whereby nutrient secretagogues enhance secretion beyond the extent established by the triggering pathway. Separating triggering from amplifying pathway should facilitate investigation of amplification. Here, we characterized the role of mitochondrial respiration during amplification. Methods: All parameters were measured by perifusion of freshly isolated mouse islets. Oxygen consumption rate (OCR) kinetics were measured by fluorescence quench technique and insulin secretion by ELISA of fractionated perifusate. Results: A 6…