Effect of chronic nicotine pre-treatment on phencyclidine (PCP) disposition in the rat.

Disposition of [3H] phencyclidine (5 mg kg-1 i.p.) in brain, liver and plasma of rats treated chronically with 0.9% saline or nicotine (1 mg kg-1 s.c. twice a day for 11 days) was studied using a method possessing high sensitivity and specificity for PCP. No significant differences were observed in the values of PCP in plasma and tissues and in brain or liver to plasma PCP concentration ratios in the 2 groups 0.5, 1, 2 hr after [3H] PCP injection. With the exception of the value of PCP metabolites in plasma at 0.5 hr, the PCP metabolites concentrations were also not significantly different in the 2 groups. Data suggested that chronic nicotine pretreatment of rats did not affect the disposition of PCP and the potentiation of PCP-induced locomotor stimulant effects by nicotine possibly involves the additive pharmacodynamic interaction of 2 compounds at the level of the central nervous system.