Damiaan Denys1, André A Klompmakers, Herman G M Westenberg. 1. Department of Psychiatry, The Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands. d.a.j.p.denys@azu.nl
Abstract
RATIONALE: The combination of atypical antipsychotic drugs in addition to serotonin reuptake inhibitors has recently proven to be beneficial in a number of neuropsychiatric disorders, such as major depression, schizophrenia, and obsessive-compulsive disorder. OBJECTIVES: To investigate the effects of an atypical antipsychotic drug in combination with a serotonin reuptake inhibitor on extracellular serotonin [5-HT]ex, and dopamine levels [DA]ex in different brain areas. METHODS: The effects of quetiapine (10 mg/kg) with fluvoxamine (10 mg/kg) on [5-HT]ex and [DA]ex were compared in the rat dorsal striatum, prefrontal cortex, nucleus accumbens (core and shell), and thalamus by means of microdialysis coupled to HPLC with electrochemical detection. RESULTS: Quetiapine had no significant effect on [DA]ex and [5-HT]ex levels in the prefrontal cortex and thalamus, but increased [DA]ex and [5-HT]ex levels in the dorsal striatum. In the accumbens, quetiapine increased [DA]ex levels and decreased [5-HT]ex levels. Fluvoxamine increased [5-HT]ex levels in all brain areas, and also increased [DA]ex levels in the striatum. The combination of quetiapine with fluvoxamine increased [DA]ex and [5-HT]ex levels in all brain areas compared with baseline. Although neither quetiapine nor fluvoxamine in monotherapy affected [DA]ex levels in the prefrontal cortex and thalamus, the combination produced a significant increase of [DA]ex levels in these two brain areas. CONCLUSIONS: The combination of quetiapine with fluvoxamine causes a synergistic dopamine increase in the prefrontal cortex and the thalamus.
RATIONALE: The combination of atypical antipsychotic drugs in addition to serotonin reuptake inhibitors has recently proven to be beneficial in a number of neuropsychiatric disorders, such as major depression, schizophrenia, and obsessive-compulsive disorder. OBJECTIVES: To investigate the effects of an atypical antipsychotic drug in combination with a serotonin reuptake inhibitor on extracellular serotonin [5-HT]ex, and dopamine levels [DA]ex in different brain areas. METHODS: The effects of quetiapine (10 mg/kg) with fluvoxamine (10 mg/kg) on [5-HT]ex and [DA]ex were compared in the rat dorsal striatum, prefrontal cortex, nucleus accumbens (core and shell), and thalamus by means of microdialysis coupled to HPLC with electrochemical detection. RESULTS:Quetiapine had no significant effect on [DA]ex and [5-HT]ex levels in the prefrontal cortex and thalamus, but increased [DA]ex and [5-HT]ex levels in the dorsal striatum. In the accumbens, quetiapine increased [DA]ex levels and decreased [5-HT]ex levels. Fluvoxamine increased [5-HT]ex levels in all brain areas, and also increased [DA]ex levels in the striatum. The combination of quetiapine with fluvoxamine increased [DA]ex and [5-HT]ex levels in all brain areas compared with baseline. Although neither quetiapine nor fluvoxamine in monotherapy affected [DA]ex levels in the prefrontal cortex and thalamus, the combination produced a significant increase of [DA]ex levels in these two brain areas. CONCLUSIONS: The combination of quetiapine with fluvoxamine causes a synergistic dopamine increase in the prefrontal cortex and the thalamus.
Authors: M Tohen; T G Jacobs; S L Grundy; S L McElroy; M C Banov; P G Janicak; T Sanger; R Risser; F Zhang; V Toma; J Francis; G D Tollefson; A Breier Journal: Arch Gen Psychiatry Date: 2000-09
Authors: J R Calabrese; S E Kimmel; M J Woyshville; D J Rapport; C J Faust; P A Thompson; H Y Meltzer Journal: Am J Psychiatry Date: 1996-06 Impact factor: 18.112