Effects of the new, non benzodiazepine, anxiolytic drug buspirone on the serotonergic system

The effects of the new, non benzodiazepine, anxiolytic drug buspirone and its metabolite 1-(2-pyrimidinyl)-piperazine (1-PP) were studied on the serotonergic system by in vivo voltammetry. This technique, in association with carbon fiber microelectrodes, chronically implanted in the hippocampus, caudate nucleus and nucleus accumbens of freely moving rats, continuously recorded 5-hydroxy-indoleacetic acid (5HIAA), the serotonin metabolite, in the extracellular space. The administration of buspirone (10 mg/kg i.p.) induced a decrease in 5HIAA in the hippocampus but not in the caudate nucleus and nucleus accumbens. This effect lasted about 150 min; 1-PP was found to be ineffective. The regional specificity of buspirone suggests a role for hippocampal serotonin in anxiety.