Reversal of stress-induced anhedonia by the atypical antidepressants, fluoxetine and maprotiline.
Chronic exposure to mild unpredictable stress has previously been found to depress the consumption of palatable sweet solutions. In the present study this effect was reversed by chronic (9 weeks) treatment with the atypical antidepressants, fluoxetine and maprotiline (5 mg/kg/day); the non-antidepressant chlordiazepoxide was ineffective. Stressed animals were also subsensitive to food reward in the place conditioning procedure; however, fluoxetine and maprotiline treated animals showed normal place preference conditioning. Acute pretreatment with raclopride (100 micrograms/kg) selectively reversed the recovery of sucrose drinking in antidepressant-treated stressed animals. These results extend previous reports of the efficacy of tricyclic antidepressants in this paradigm, and support the hypothesis of a dopaminergic mechanism of antidepressant action.
Department of Psychology, City of London Polytechnic, UK.
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Muscat
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Papp
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Willner
D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000494:pharmacology*; D002707:Chlordiazepoxide / Q000494:pharmacology; D003216:Conditioning, Operant / Q000187:drug effects*; D004298:Dopamine / Q000502:physiology; D004435:Eating / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D005473:Fluoxetine / Q000494:pharmacology*; D005502:Food; D008297:Male; D008376:Maprotiline / Q000494:pharmacology*; D051381:Rats; D012201:Reward; D013315:Stress, Psychological / Q000523:psychology*; D013395:Sucrose / Q000494:pharmacology
D018687:Antidepressive Agents, Second-Generation; D005473:Fluoxetine; D008376:Maprotiline; D013395:Sucrose; D002707:Chlordiazepoxide; D004298:Dopamine