Differences in the oxygen consumption pattern suggest that nutrient-induced insulin secretion is differentially regulated in primary mouse islets and MIN6 pseudo-islets

Background and aims: In addition to plasma membrane depolarization metabolic amplification is required for the full extent of nutrient-induced insulin secretion. For metabolomic investigations insulin-secreting cell lines, such as MIN6, are utilized. The relevance of such data is, however, unclear. Methods: All parameters were measured by perifusion of freshly isolated mouse islets or of MIN6 pseudo-islets. The oxygen consumption was measured by a fluorescence quenching technique, the free cytosolic Ca2+ concentration ([Ca2+]i) by imaging after loading with Fura and the insulin secretion by ELISA of the fraction…