GMP PROTECTS AGAINST QUINOLINIC ACID-INDUCED LOSS OF NADPH-DIAPHORASE-POSITIVE CELLS IN THE RAT STRIATUM

When injected into the rat striatum, quinolinic acid causes dose-depen dent widespread cell death. All cell types, including the NADPH-diapho rase-positive neurons appear to be sensitive to the toxin. The latter cells are destroyed by quinolinic acid injections of 180 nmol per stri atum, this effect being blocked by the concomitant administration of 5 mg/kg of the non-competitive N-methyl-D-aspartate antagonist MK-801. We report that guanosine-5'-monophosphate (GMP), at a dose of 360 nmol , is equally effective in protecting the diaphorase positive cells aga inst quinolinate toxicity. (C) 1997 Elsevier Science Ireland Ltd.