Combined treatment with NMDA antagonist, CGP 37849, and sigma receptor agonists, SA4503 or DTG, decreases the neuroleptic-induced catalepsy in rats.

The obtained results indicate that joint administration of CGP 37849, a competitive NMDA receptor antagonist, and SA4503, a sigma1 (sigma1) receptor agonist or DTG, sigma 1/2 receptor agonist, evoked anticataleptic effect at doses which were ineffective when each of the compounds was given alone.