Prohedonic Effect of Cannabidiol in a Rat Model of Depression

Background: Accumulating evidence suggests that cannabidiol (CBD) may be an effective and safe anxiolytic agent and potentially also an antidepressant. Aim: The objective of this study was to further examine these properties of CBD using the 'depressive-like' Wistar-Kyoto (WKY) rat, focusing on the drug's effect on anhedonia-like behaviors. Methods: Forty-eight WKY and 48 control Wistar adult male rats were pretreated orally with CBD (15, 30 and 45 mg/kg) or vehicle. The saccharin preference test (SPT), the elevated plus maze (EPM) test and the novel object exploration (NOE) test were used. Results: CBD showed a prohedonic effect on the WKY rats at 30 mg/kg in the SPT. In the NOE, CBD increased exploration of the novel object and locomotion at 45 mg/kg and increased locomotion at 15 mg/kg, indicating an improvement in the characteristically low motivation of WKY rats to explore. There was no similar effect at any dose in the EPM or in open-field behavior in the habituation to the NOE. Conclusions: These findings extend the limited knowledge on the antidepressant effect of CBD, now shown for the first time in a genetic animal model of depression. These results suggest that CBD may be beneficial for the treatment of clinical depression and other states with prominent anhedonia. (C) 2016 S. Karger AG, Basel