Osmotic swelling of beta-cells is a potent stimulus for insulin release and is accompanied by the activation of regulatory volume decrease (RVD) anion channels/currents (RVDC). RVDC in Ins-1E cells have an increased basal activity in isotonic low glucose (5 mM) compared to glucose-free extracellular solution and are further activated by hypoosmotic (30%) cell swelling. The current displays outward rectification, time-dependent inactivation at positive potentials and is inhibited by the anion channel blocker DIDS. Increasing the glucose concentration to 20 mM under isotonic conditions elicits an outwardly rectifying current with varying activation kinetics at positive potentials. In the presence of nifedipine the current amplitude is reduced and clear time dependent inactivation can be observed, indicating the involvement of a calcium-sensitive current component. FRET experiments reveal that glucose induces an association of ICln, a protein involved in the activation of RVDC, with the cell membrane. Activation of RVDC might be important for the regulation of insulin secretion from beta-cells under normo- and hyperglycemic conditions when ATP-sensitive potassium-channels are closed.