Effects of single and repeated phencyclidine administration on the expression of subunit mRNA for NMDA receptors in rat brain

To investigate the effects of phencyclidine (PCP) on N-methyl-d-aspartate (NMDA) receptors, we examined the effects of both single and repeated administrations of PCP on the NMDA receptor subunits in rat brain using in situ hybridization. Intraperitoneal (i.p.) administration of a daily dose of 7.5mg/kg PCP resulted in significantly decreased in expression of NMDAR2A subunit mRNA in the cingulate cortex Ih after a single administration. Repeated PCP administrations for 14 days resulted in significantly decreased the expression of NMDAR1(-) mRNA in the nucleus accumbens and piriform cortex. These results suggest that region-specific decreases of NMDA receptor subunits may represent a compensatory response to enhanced glutamate availability in the limbic region.