Effect of phencyclidine and two monohydroxy metabolites on 3H QNB binding in vivo in rats

The purpose of these investigations was to determine if phencyclidine (PCP) and/or two of its major monohydroxy metabolites [1-(1-phenylcyclohexyl)4-hydroxy piperidine (4-OH-pip PCP) and 1-(1-phenyl-4-hydroxycyclohexyl) piperidine (4-OH-cyclo PCP)] influence 3H quinuclidinyl benzilate (QNB) binding in rat brain after in vivo administration. PCP and 4-OH-pip PCP but not 4-OH-cyclo PCP enhanced QNB binding. The effect was blocked by atropine. Since the dose of 4-OH-pip PCP necessary to alter QNB binding in rat brain is substantially higher than that required for PCP, this metabolite probably does not play a major role in the PCP effect on QNB binding in rat brain.