title: Repeated Cocaine Experience Facilitates Sucrose-Reinforced Operant Responding in Enriched and Isolated Rats.
abstract: The purpose of the present experiment was to determine whether repeated cocaine exposure differentially affects sucrose-reinforced operant responding in rats raised in an enriched condition (EC) or an isolated condition (IC). Specifically, the performance of EC and IC rats pressing a lever for sucrose under a high fixed-ratio schedule (FR 30) prior to and after 10 days of exposure to cocaine (15 mg/kg, i.p.) or saline was compared. Regardless of rearing condition, rats repeatedly exposed to cocaine had shorter reacquisition latencies to complete a sucrose-reinforced FR 30 task than saline controls. The results suggest that cocaine exposure may have cross-sensitized both EC and IC rats to the reinforcing effects of sucrose or sucrose-associated cues, thus facilitating reacquisition of operant responding.
authors.affiliation: University of Kentucky.
authors.forename: Emily D
authors.initials: ED
authors.lastname: Klein
authors.affiliation: University of Kentucky.
authors.forename: Brenda J
authors.initials: BJ
authors.lastname: Gehrke
authors.affiliation: University of Kentucky.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Green
authors.affiliation: University of Kentucky.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Zentall
authors.affiliation: University of Kentucky.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bardo
keywords: Cocaine; Environmental Enrichment; Fixed Ratio; Locomotor; Sensitization; Sucrose