Functional neuronal ionotropic glutamate receptors are expressed in the non-neuronal cell line MIN6

We report that a non-neuronal cell line, MIN6, derived from insulin-secreting pancreatic beta-cells, naturally expresses functional ionotropic glutamate receptors. Electrophysiological recordings show that kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA), and N-methyl-D-aspartate (NMDA) depolarize single MIN6 cells and evoke inward ionic currents. These agents also increase the intracellular calcium concentration in MIN6 cells. Furthermore, insulin secretion from MIN6 cells is stimulated by kainate, AMPA, and NMDA. The presence of AMPA/kainate and NMDA receptor subtypes is confirmed by reverse transcriptase-polymerase chain reaction. These results demonstrate that ionotropic glutamate receptors with properties similar to those in neuronal cells are expressed in a non-neuronal cell line, MIN6. Thus, MIN6 provides a useful and valuable model system for biochemical, pharmacological, and physiological studies of ionotropic glutamate receptors.