The role of 5-hydroxytryptamine receptor subtypes in the regulation of brain-derived neurotrophic factor gene expression.

Objectives: The study aims to investigate the role of 5-hydroxytryptamine receptor subtypes in mediating the inhibitory effect of the selective serotonin reuptake inhibitor (fluoxetine on brain-derived neurotrophic factor gene (bdnf) expression in rat hippocampus.

Methods: In situ hybridization was used for regional determination of bdnf expression levels in hippocampal brain slices from normal, lesioned (5-hydroxytryptamine or noradrenaline) or adrenalectomized rats; treated with fluoxetine and/or 5-hydroxytryptamine selective ligands.

Key Findings: Our study shows that the transient fluoxetine-induced down-regulation of bdnf gene expression depends on an intact 5-hydroxytryptamine but not noradrenaline system or circulating glucocorticoids.