7/23/1996 • Effect of acute and chronic fluoxetine on extracellular dopamine levels in the caudate-putamen and nucleus accumbens of rat.

7/23/1996 • Effect of acute and chronic fluoxetine on extracellular dopamine levels in the caudate-putamen and nucleus accumbens of rat.

Clark RN, Ashby CR Jr, Dewey SL, Ramachandran PV, Strecker RE
Department of Psychiatry and Behavioral Sciences, State University of New York at Stony Brook 11794, USA.

Synapse 1996; Jul; 23 (3); 125-31

Extracellular levels of the 5-HT metabolite 5HIAA were consistently decreased at all doses of fluoxetine in both structures.

Effect of acute and chronic fluoxetine on extracellular dopamine levels in the caudate-putamen and nucleus accumbens of rat.

http://www.ncbi.nlm.nih.gov/htbinpost/Entrez/query?uid=8807740&form=6&db=m&Dopt=b

Clark RN, Ashby CR Jr, Dewey SL, Ramachandran PV, Strecker RE
Department of Psychiatry and Behavioral Sciences, State University of New York at Stony Brook 11794, USA.

Synapse 1996; Jul; 23 (3); 125-31

Extracellular levels of the 5-HT metabolite 5HIAA were consistently decreased at all doses of fluoxetine in both structures.

Recent studies indicate that an increase in serotonergic (5-HT) activity in the nucleus accumbens (NAc) produces an increase in dopamine (DA) release, providing a possible mechanism for the involvement of DA in the therapeutic action of selective serotonin reuptake inhibitor (SSRI) antidepressants. However, acutely administered fluoxetine (2.5, 5.0, or 10.0 mg/kg, i.p.) failed to elevate extracellular levels of DA, or its metabolites in the NAc or caudate-putamen (CP). In fact, the highest dose produced a small (20%) decrease in DA levels in the NAc. Extracellular levels of the 5-HT metabolite 5HIAA were consistently decreased at all doses of fluoxetine in both structures. Since SSRIs generally require several weeks of treatment to be effective clinically, a second experiment examined the effect of chronic administration of fluoxetine. Chronic (21 day) daily treatment with 5 mg/kg had no effect on NAc basal levels of DA, DA metabolites, or 5HIAA, relative to a saline-treated control group. Finally, pretreatment with fluoxetine appeared to slightly enhance the elevation of NAc DA induced by an injection of cocaine (10 mg/kg, i.p.), an effect that was not quite significant (P < .06). In conclusion, the 5-HT-induced facilitation of NAc DA neurotransmission described in the literature may not be relevant to the therapeutic action of fluoxetine. PMID: 8807740, UI: 96401364

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4/15/1993 • Cerebrospinal fluid monoamine metabolites in fluoxetine-treated patients with major depression and in healthy volunteers.

4/15/1993 • Cerebrospinal fluid monoamine metabolites in fluoxetine-treated patients with major depression and in healthy volunteers.

De Bellis MD, Geracioti TD Jr, Altemus M, Kling MA
Clinical Neuroendocrinology Branch, National Institute of Mental Health,National Institute of Health, Bethesda, Maryland.

Biol Psychiatry 1993 Apr 15-May 1; 33 (8-9); 636-41

CSF 5-HIAA and MHPG decreased significantly… following fluoxetine treatment.
Cerebrospinal fluid monoamine metabolites in fluoxetine-treated patients with major depression and in healthy volunteers.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7687151&dopt=Abstract

De Bellis MD, Geracioti TD Jr, Altemus M, Kling MA
Clinical Neuroendocrinology Branch, National Institute of Mental Health,National Institute of Health, Bethesda, Maryland.

Biol Psychiatry 1993 Apr 15-May 1; 33 (8-9); 636-41

CSF 5-HIAA and MHPG decreased significantly… following fluoxetine treatment.

Cerebrospinal fluid (CSF) levels of the monoamine metabolites 5-hydroxyindoleacetic acid (5-HIAA), 3-methoxy-4-hydroxyphenylglycol (MHPG), and homovanillic acid (HVA) were measured in three groups: 46 healthy volunteers; 9 medication-free patients with DSM III-R major depressive disorder, recurrent; and these same 9 patients following at least 4 weeks of fluoxetine treatment at 20 mg/day. CSF monoamine metabolite levels in medication-free patients did not differ from healthy volunteers; however, CSF 5-HIAA and MHPG decreased significantly from 95.9 +/- 24.6 (all values +/- SD) to 64.2 +/- 26.1 pmol/ml and from 46.7 +/- 14.2 to 42.6 +/- 11.6 pmol/ml, respectively, following fluoxetine treatment. Fluoxetine also significantly decreased mean Hamilton Depression Rating Scale scores from 23.2 +/- 6.5 to 17.4 +/- 5.0 and significantly increased the CSF HVA/5-HIAA ratio.
PMID: 7687151, UI: 93320172

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5/17/1975 • Fenfluramine in man: hypophagia associated with diminished serotonin turnover.

5/17/1975 • Fenfluramine in man: hypophagia associated with diminished serotonin turnover.

Shoulson I, Chase TN

Clin Pharmacol Ther 1975 May 17(5) 616-21

The results support the contention that the effect of fenfluramine on human dietary intake may be mediated by alterations in serotonergic rather than dopaminergic mechanisms.
Fenfluramine in man: hypophagia associated with diminished serotonin turnover.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1092516&dopt=Abstract

Shoulson I, Chase TN

Clin Pharmacol Ther 1975 May 17(5) 616-21

The results support the contention that the effect of fenfluramine on human dietary intake may be mediated by alterations in serotonergic rather than dopaminergic mechanisms.

A double-blind trial of orally administered fenfluramine was conducted in 7 non-obese adults with various neurological disorders. Caloric intake and body weight fell significantly after 8 days of treatment although there was no definite change in appetite ratings. Average central turnover of serotonin, as estimated by the cerebrospinal fluid (CSF) accumulation of 5-hydroxyindoleacetic acid (5-HIAA) during probenecid loading, decreased by 66%. No significant change in homovanillic acid, the major dopamine product, was apparent.
Publication Types: Clinical trial Controlled clinical trial PMID: 1092516, UI: 75148833

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