N-Methyl-D-aspartate acid: a convulsant with weak neurotoxic properties.

N-Methyl-D-aspartic acid (NMDA) is 100-fold less potent as a neurotoxin than kainic acid when injected into the rat striatum. However, NMDA, when injected into the hippocampus, causes a more severe seizure disorder than kainic acid and doses of NMDA than produce much smaller lesions than those caused by kainate. These results indicate a poor correlation between convulsant and neurotoxic properties of acidic excitatory amino acids.