Neurotoxicity evoked by N-methyl-d-aspartate in the organotypic static slice cultures of rat cerebral cortices: effect of GABAA receptor activation

We investigated the neurotoxicity evoked by N-methyl-d-aspartate (NMDA) receptor stimulation in the organotypic static slice cultures of rat cerebral cortices. We also examined whether the γ-aminobutyric acid (GABA)_A receptor agonist muscimol has a protective effect on the NMDA-mediated neurotoxicity in this culture system. NMDA-mediated cytotoxicity was evaluated histologically and quantified by the measurement of lactate dehydrogenase (LDH) release into the culture medium. There was an NMDA-induced, dose-dependent leakage of LDH release and neuronal cell death, which were not attenuated by muscimol treatment. The results suggested that NMDA neurotoxicity is reproduced in the organotypic culture, and that GABA_A receptor activation exerted no protective action against the NMDA cytotoxicity. Received: 25 July 1997 / Revised, accepted: 1 December 1997