Dipeptides--analogues of N-acetylaspartylglutamate inhibit convulsive effects of excitatory amino acids in mice.

The effects of three dipeptide analogues of N-acetylaspartylglutamate on seizures elicited by intracerebroventricular (i.c.v.) injection of L-glutamate (GLU), N-methyl-D-aspartate (NMDA), kainate (KA) and intraperitoneal (i.p.) injection of pentylentetrazol (PTZ) were studied in mice. N-Ac-L-Phe-L-Glu was active against myoclonic seizures induced by GLU and NMDA under simultaneous i.c.v. injection. All dipeptides were ineffective against KA and PTZ convulsions. The anticonvulsant activity and potency of N-Ac-L-Phe-L-Glu were similar to that of gamma-D-glutamylglycine (gamma-DGG) for excitatory amino acids (EAA) induced seizures. These results indicate EAA antagonistic activity among dipeptides which have L-glutamic acid on C-terminal and acetylated N-terminal.