Subchronic milnacipran treatment increases basal extracellular noradrenaline concentrations in the medial prefrontal cortex of rats

In this study, we investigated the acute effects of milnacipran, a serotonin-noradrenaline reuptake inhibitor, following subchronic treatment with milnacipran (30 mg/kg periorally for 7 days) on extracellular noradrenaline, dopamine and serotonin concentrations in the medial prefrontal cortex. Subchronic administration of milnacipran produced significantly higher basal levels of extracellular noradrenaline. Acute milnacipran administration following subchronic milnacipran treatment for 7 days produced a greater increase in extracellular noradrenaline than a single dose of milnacipran alone. The present results suggest that subchronic milnacipran treatment enhances noradrenergic neural transmission beyond that achieved with acute administration of milnacipran alone, but has no effect on serotonergic or dopaminergic neural transmission. (c) 2005 Elsevier B.V. All tights reserved.