Augmented accumbal serotonin levels decrease the preference for a morphine associated environment during withdrawal.

G C Harris; G Aston-Jones

doi:10.1016/s0893-133x(00)00184-6

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Augmented accumbal serotonin levels decrease the preference for a morphine associated environment during withdrawal.

G C Harris·G Aston-Jones

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Abstract

Recent studies have found that acute morphine administration increases serotonin (5-HT) transmission within the nucleus accumbens and other forebrain regions. In contrast, 5-HT transmission is depressed during withdrawal from chronic morphine. We show that pharmacological agents that increase brain 5-HT levels (fluoxetine or 5-hydoxytryptophan, 5-HTP) abolish the preference of chronically morphine-treated, withdrawn rats for a morphine-associated environment. Similar results were seen when fluoxetine was microinjected into the nucleus accumbens. Conversely, rats given morphine acutely showed an enhanced preference for a morphine-associated environment when pretreated with these agents. Fluoxetine also decreased the heightened anxiety found in morphine withdrawn rats. The results of our study indicate that drugs that augment 5-HT levels may reduce the desire for morphine during withdrawal.

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5-Hydroxytryptophan Animals Anxiety Conditioning, Psychological Drug Administration Schedule Environment, Controlled Fluoxetine Head Movements Male Morphine Morphine Dependence Neurons Nucleus Accumbens Rats Rats, Sprague-Dawley Serotonin Substance Withdrawal Syndrome Journal Article Research Support, U.S. Gov't, P.H.S.

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G C Harris, G Aston-Jones. 2001. Augmented accumbal serotonin levels decrease the preference for a morphine associated environment during withdrawal.. https://doi.org/10.1016/s0893-133x(00)00184-6

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