Effects of acute and continuous administration of pentobarbital on phencyclidine response

In mice acutely treated with Na-pentobarbital, the phencyclidine (PCP) induced motor incoordination was significantly enhanced. On the other hand, in mice rendered tolerant to pentobarbital by pentobarbital pellet implantation, PCP induced motor incoordination was markedly attenuated. The biochemical studies also revealed that acute administration of pentobarbital slowed down the rate of decay of PCP in brain and serum. In contrast, the rate of PCP disappearance in pentobarbital tolerant mice was significantly accelerated. It appears that the effects of pentobarbital on PCP response are dependent on its influence on PCP metabolism.