Effects of acute olanzapine after sustained fluoxetine on extracellular monoamine levels in the rat medial prefrontal cortex.
The combination of selective serotonin reuptake inhibitors with atypical antipsychotic drugs exhibits beneficial effects in treatment-resistant depression. We investigated the effects of a 2-week treatment with a low fluoxetine dose (3 mg/kg per day) plus a single injection of olanzapine (3 mg/kg) on the dialysate concentration of noradrenaline, dopamine and serotonin (5-HT) in the medial prefrontal cortex of the rat. Chronic fluoxetine increased only 5-HT levels whereas single olanzapine administration increased the concentration of catecholamines and decreased that of 5-HT to a comparable extent in vehicle- and fluoxetine-treated rats. Therefore, it is possible that the therapeutic benefit of this pharmacological combination may not be associated to changes in the cortical concentration of monoamines, but to postsynaptic blockade of monoaminergic receptors.
Amargós-Bosch
Mercè
M
Department of Neurochemistry, Instituto de Investigaciones Biomédicas de Barcelona, CSIC (IDIBAPS), Calle Rosellón 161, 6th floor E-08036 Barcelona, Spain.
Artigas
Francesc
F
Adell
Albert
A
D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology; D001569:Benzodiazepines / Q000494:pharmacology; D015306:Biogenic Monoamines / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D005473:Fluoxetine / Q000494:pharmacology*; D008297:Male; D017551:Microdialysis; D009638:Norepinephrine / Q000378:metabolism; D000077152:Olanzapine; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D015306:Biogenic Monoamines; D004298:Dopamine; D005473:Fluoxetine; D009638:Norepinephrine; D000077152:Olanzapine; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors