Attenuation of the effects of d-amphetamine on interval timing behavior by central 5-hydroxytryptamine depletion

Abstract
Interval timing in the free-operant psychophysical procedure is sensitive to the monoamine-releasing agent d-amphetamine, the D2-like dopamine receptor agonist quinpirole, and the D1-like agonist 6-chloro-2,3,4,5-tetrahydro-1-phenyl-1H-3-benzepine (SKF-81297). The effect of d-amphetamine can be antagonized by selective D1-like and 5-HT2A receptor antagonists. It is not known whether d-amphetamine’s effect requires an intact 5-hydroxytryptamine (5-HT) pathway.