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Updated: Aug 13, 2026

A Protocol for Measuring Cue Reactivity in a Rat Model of Cocaine Use Disorder
Published on: June 18, 2018
Cocaine craving, euphoria, and self-administration: a preliminary study of the effect of catecholamine precursor
Marco Leyton1, Kevin F Casey, J Scott Delaney
1McGill University, Department of Psychiatry, Montreal, PQ, Canada. marco.leyton@mcgill.ca
Abstract:
The authors used the acute phenylalanine-tyrosine depletion (APTD) method to test the effect of transient catecholamine precursor depletion on cocaine craving, euphoria, and self-administration. Eight nondependent, nontreatment-seeking cocaine users self-administered 3 doses of cocaine (0.6, 1.5, 3.0 mg/kg, taken intranasally) following ingestion of (a) a nutritionally balanced amino acid mixture, (b) APTD, and (c) APTD followed by L-dopa/carbidopa (2x100 mg/25 mg). APTD decreased both cue and cocaine-induced drug craving but not euphoria or self-administration. APTD+L-dopa also decreased drug craving, possibly reflecting the ability of L-dopa to transiently decrease dopamine cell firing. Together, these preliminary results suggest that the craving elicited by cocaine and cocaine cues is related to changes in catecholamine neurotransmission. Euphoria and the self-administration of freely available drugs by regular users, in comparison, might be better accounted for by other mechanisms.
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