IC50: 19.1 nM JO 1784 is a selective σ1 receptor ligand. The CNS σ receptor ligands, as is known, modulates central neurotransmitter systems ( noradrenergic-, glutaminergic-, and dopaminergic-neurons was included). In vitro: Compared with control, data obtained displayed significant reduction in the densities of β-adrenergic, but not σ1, 5-HT1A, and GABAB receptors in fluoxetine (18%), desipramine (DMI, 32%) and JO 1784 (20%)-treated groups. Tyrosine hydroxylase (TH) activity was significantly (30–32%) decreased in all treated groups. Further, fluoxetine and DMI excluding the JO 1784 -treated groups diaplayed 85 and 40% reductions in serotonin (5-HT) and noradrenaline (NE) neuronal uptake, respectively. Following acute treatment, JO 1784 is inactive for monoamine oxidase (MAO) A or B . In vivo: In vivo studies, JO 1784 at behaviorally active doses exhibited weak effects on the NE uptake but has no activity in altering 5-HT and DA synthesis or antagonizing selective drug-stimulated depletion of monoamine neuronal uptake. NMDA-induced potentiates cGMP was inhibited by JO 1784, indicating that JO 1784 may interfere with the NMDA receptor/NOS/cGMP pathway. Although it appears that the pharmacological actions of JO 1784 partially is modulated by the monoaminergic system, there is still need to find other possible mechanisms of antidepressant action . Clinical trial: So far, no clinical study has been conducted.