This study investigated whether D,L-cis-2,3-Pyrrolidine dicarboxylate (D,L-cis-2,3-PDC), a new glutamate analogue, alters glutamate binding to cerebral plasma membranes and whether N-methyl-D-aspartate (NMDA) receptors are involved in the convulsant effect of this compound. D,L-cis-2,3-PDC reduced sodium-independent [H-3]-L-glutamate binding to lysed membrane preparations from adult rat cortex and had no effect on sodium-dependent glutamate binding. Intracerebroventricular administration Of D,L-cis-2,3-PDC (7.5-25 nmol/5 mul) induced generalized tonic-clonic convulsions in mice in a dose-dependent manner. The coadministration of MK-801 (7 nmol/2.5 mul), with D,L-cis-2,3-PDC (16.5 nmol/2.5 mul), fully protected the animals against D,L-cis-2,3-PDC-induced convulsions, while the coadministration of DNQX (10 nmol/2.5 mul) increased the latency to convulsions but did not alter the percentage of animals that had convulsions. These results suggest that D,L-cis-2,3-PDC-induced effects are mediated predominantly by NMDA receptors. (C) 2003 Elsevier Inc. All rights reserved.762295299