Cultured motor neurons possess calcium-permeable AMPA/kainate receptors

WE examined the biology of AMPA/kainate-induced motor neuron degeneration u sing dissociated spinal cord cultures and motor neuron-specific antibodies which enable characterization of individual motor neurons in culture. Cobal t, which is thought to pass through Ca2+-permeable AMPA/kainate receptors f ollowing kainate exposure, labeled motor neurons in spinal cord cultures. T he analysis of AMPA subunit distribution in dissociated motor neurons revea led a unique pattern of glutamate receptor (GluR) subunits in those cells; the GluR1 subunit was found in all spinal cord neurons, but the GluR2 subun it was not found in identified dissociated motor neurons. These data sugges t that selective sensitivity of motor neurons to non-NMDA receptor activati on is due, at least in part, to the presence of Ca2+-permeable AMPA/kainate receptors. NeuroReport 10:855-859 (C) 1999 Lippincott Williams & Wilkins.