Electrophysiological properties of glial cells: comparison of brain slices with primary cultures.

Intracellular recordings were obtained from glial cells in the CA1 region of rat hippocampal slices to compare their electrophysiological properties with the previously reported properties of glial cells in primary tissue culture. The average resting potential was -77 mV and the average input resistance was 3.2 M omega. Barium (10 mM) depolarized glial cells in brain slices and increased input resistance, but barium action potentials which have been observed in primary cultures, were not observed in brain slices. gamma-aminobutyric acid (GABA) and glutamate depolarized glial cells. Spontaneous oscillations of membrane potential were observed occasionally. The mechanism underlying these responses are unknown as yet.