CGP-39653 BINDING IN THE CHICK CNS AFTER NMDA RECEPTOR ANTAGONIST TREATMENT

To analyze the affect of blocking neuronal activity on NMDA receptor l evels during development, we have injected chick embryos with the comp etitive NMDA receptor antagonist NPC 12626 from E17 to E19. Brains fro m drug-treated (n = 7) and control (n = 6) embryos (E20) were processe d for receptor autoradiography using the NMDA competitive antagonist [ H-3]CGP 39653. NPC 12626 treatment caused a significant 24 to 46% incr ease in [H-3]CGP 39653 binding in both the forebrain and cerebellar co rtex. The results support the hypothesis that NMDA receptor levels are regulated by activity-dependent mechanisms.