The effects of chronic administration of phencyclidine (PCP) or CGS 19755 (cis-4-phosphonomethyl-2-piperidine-carboxylic acid) on the cataleptic effects of N-methyl-D-aspartate (NMDA) receptor antagonists were studied in pigeons. PCP, a channel blocker of the NMDA receptor complex, or CGS 19755, a competitive NMDA antagonist, was administered i.m. to separate groups of pigeons each day....
MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5, 10-imine maleate] and related compounds were studied in monkeys discriminating between 0.032 mg/kg of (+)-MK-801 and saline and in a separate group of monkeys responding under a multiple schedule of repeated acquisition and performance of conditional discriminations. In the drug discrimination study, small doses of (+)-MK-801...