Stereospecific antagonism by (+)-alpha-methyl-4-carboxyphenylglycine (MCPG) of (1S,3R)-ACPD-induced effects in neonatal rat motoneurones and rat thalamic neurones.

The (+)-enantiomer of alpha-methyl-4-carboxyphenylglycine (MCPG) stereoslectively antagonized the depolarization of neonatal rat motoneurones and the excitation of rat thalamic neurons induced by the specific metabotropic glutamate receptor agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate (ACPD). (+)-MCPG preferentially reduced (1S,3R)-ACPD-induced responses relative to responses induced by (S)-alpha-amino-3-hydorxy-5-methylisoxazole-4-propionic acid (AMPA) and N-methyl-D-aspartate (NMDA).