Action of GABA and glycine on the membrane potential of cultured astrocytes and the extracellular K+-concentration

The depolarization of cultured astrocytes by GABA and glycine correlates in amplitude and time course with the increase of the extracellular K+-concentration during perfusion with these amino acids. It is suggested that the glial depolarization is caused by an efflux of K+ from neighbouring neurones activated by the amino acid transmitters.