Responses to gamma-aminobutyric acid applied to cell bodies and dendrites of rat visual cortical neurons.

The effects of pressure-applied gamma-aminobutyric acid (GABA) on the soma and dendrites of pyramidal and non-pyramidal neurons of rat visual cortical slices were recorded intracellularly. When applied close to the soma, GABA produced hyperpolarizations and depolarizations, but when GABA was applied more than 250 microns from the soma only depolarizations were recorded. The results suggest that most visual cortical cells respond to GABA and that the responses of pyramidal and non-pyramidal cells to GABA are similar.