Development of GABA neurons in dissociated cell culture of rat cerebral cortex

Abstract

Cortical neurons dissociated from newborn rat brain were maintained on supporting glial monolayers in the presence of the mitotic inhibitor, FUdR. The ability of this type of primary culture (NG) to synthesize, store, metabolize, accumulate and release GABA was compared to that of neuron-free glial monolayers (G) cultured under the same conditions. While NG cultures synthesized and stored GABA, there was little GABA, or GABA-synthesizing activity (GAD) in G cultures. In contrast, appreciable activities of the GABA catabolizing enzyme, GABA-T, were present in both cultures. Furthermore, accumulation of GABA by high affinity uptake and K +-stimulated release of GABA were associated exclusively with the neurons. Morphological differentiation, GABA metabolism, uptake and release increased with increasing time in culture. The present evidence suggests that the NG preparation may represent a good model system to study GABA-mediated transmission in culture.