Befiradol (F13640; NLX-112) reduces the activity of dorsal raphe serotonergic neurons at 0.2-18.2 μg/kg, i.v. (cumulative doses; ED50=0.69 μg/kg, i.v.) and increases the discharge rate of 80% of mPFC pyramidal neurons in the same dose range (ED50=0.62 μg/kg, i.v.). Both effects are reversed by the subsequent administration of the 5-HT1A receptor antagonist (±)WAY100635. In microdialysis studies, Befiradol (F13640; NLX-112) (0.04-0.63 mg/kg, i.p.) dose-dependently decreases extracellular 5-HT in the hippocampus and mPFC. Likewise, Befiradol (F13640; NLX-112) (0.01-2.5 mg/kg, i.p.) dose-dependently increases extracellular DA in mPFC, an effect dependent on the activation of postsynaptic 5-HT1A receptors in mPFC. Local perfusion of Befiradol in mPFC (1-1,000 μM) also increases extracellular DA in a concentration-dependent manner. Both the systemic and local effects of Befiradol are prevented by prior (±)WAY100635 administration[1].