Glucose-induced changes in the redox state of pancreatic non-B islet cells

Pancreatic islet B and non-B cells prelabelled with the calcium-sensitive fluorochrome Fluo-3 were examined in a single step procedure of flow cytometry. Increasing concentrations of D-glucose, in the 1.0-20.0 mM range, were found to cause a progressive rise in the NAD(P)H content of the islet non-B cells. This coincided with a dual change in the intracellular Ca2+ concentration in the same cells. In the non-B cells, the forward scatter of light was little affected, however, by changes in D-glucose concentration. These findings are compared with those found, within the same experiments, in purified islet B-cells, with the emphasis on the differences between the two cell populations in their responsiveness to D-glucose, in terms of changes in both redox state and Ca2+ cell content.