Antidepressant-Like Effect of Venlafaxine Is Abolished in μ-Opioid Receptor–Knockout Mice

Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Japan.
Journal of Pharmacological Sciences (Impact Factor: 2.36). 01/2010; 114(1):107-10. DOI: 10.1254/jphs.10136SC
Source: PubMed


Although the opioid system is known to modulate depression-like behaviors, its role in the effects of antidepressants is not yet clear. We investigated the role of μ-opioid receptors (MOPs) in the effects of venlafaxine, a serotonin and norepinephrine reuptake inhibitor, in the forced swim test using MOP-knockout (KO) mice. Venlafaxine reduced immobility time in wild-type mice (C57BL/6J), but not in MOP-KO mice, although no significant effects were observed on locomotor activity. These results suggest that MOPs play an important role in the antidepressant-like effects of venlafaxine.

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Available from: Kazutaka Ikeda
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