Depolarization of cultured oligodendrocytes by glutamate and GABA

Subpopulations of cultured oligodendrocytes from mouse spinal cord respond with depolarization to glutamate and GABA. Heterogeneity in the oligodendrocyte population was indicated by the observation that some cells respond to both GABA and glutamate, while others respond to only one and some are not responsive to either. Depolarizations are not mediated by an increase of [K+]o released from neurons. The response to GABA was blocked in Na+-free solution and is not accompanied by a change in input resistance. Several other neurotransmitters did not induce changes in membrane potential.