Examining the reinforcement-enhancement effects of phencyclidine and its interactions with nicotine on lever-pressing for a visual stimulus.
Behavioural brain research September 15, 2015 Natashia Swalve, Scott T Barrett, Rick A Bevins et al.
Nicotine and phencyclidine (PCP) each separately increased rats' lever-pressing for a brief visual stimulus, indicating a reinforcement-enhancement effect. The effect was dose-dependent for nicotine (0.2 or 0.4 mg/kg) and present with PCP (2.0 mg/kg) across increasing fixed-ratio schedules. Adding PCP to nicotine did not further increase lever-pressing, possibly due to a ceiling effect. PCP's effect appeared driven largely by locomotor stimulation, whereas nicotine's effect was independent of locomotor activity. This dissociation suggests that different pharmacological properties underlie the reinforcement-enhancement effects of these substances.