Fluoxetine pretreatment reduces breaking points on a progressive ratio schedule reinforced by intravenous cocaine self-administration in the rat.
Fluoxetine, a specific serotonin re-uptake inhibitor, reduced the breaking points reached by rats on a progressive ratio (PR) schedule reinforced by intravenous cocaine (0.6 mg/inj). This effect was dose-dependent. Specifically, fluoxetine (2.5, 5.0, 10.0, and 20.0 mg/kg, IP) significantly decreased breaking points at all but the lowest dose. These data support a role for the serotonergic system in cocaine reinforcement. We argue that facilitating serotonergic activity reduces the rewarding value of cocaine, thus suggesting an aversive role for serotonin in cocaine reinforcement.
Richardson
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Department of Psychology, Carleton University, Ottawa, Canada.
Roberts
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DC
D000818:Animals; D003042:Cocaine / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005473:Fluoxetine / Q000494:pharmacology*; D007262:Infusions, Intravenous; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012651:Self Medication; D012701:Serotonin / Q000378:metabolism
D005473:Fluoxetine; D012701:Serotonin; D003042:Cocaine