Cannabidiol Exerts Sedative and Hypnotic Effects in Normal and Insomnia Model Mice Through Activation of 5-HT Receptor.

Cannabis sativa has been used for improving sleep for long history. Cannabidiol (CBD) has drown much attention as a non-addictive psychoactive component in Cannabis sativa extract. However, the effects of CBD on sleep architecture and it's acting mechanism remains unclear. In the present study, we evaluated the sedative-hypnotic effect of cannabidiol (CBD), assessed the effects of CBD on sleep using a wireless physiological telemetry system. We further explored the therapeutic effects of CBD using 4-chloro-dl-phenylalanine (PCPA) induced insomnia model and changes in sleep latency, sleep duration and intestinal flora were evaluated. CBD shortened sleep latency and increases sleep duration in both normal and insomnia mice, and those effects were blocked by 5-HT receptor antagonist WAY100635. We determined that CBD increases 5-HT receptors expression and 5-HT content in the hypothalamus of PCPA-pretreated mice and affects tryptophan metabolism in the intestinal flora. These results showed that activation of 5-HT receptors is one of the potential mechanisms underlying the sedative-hypnotic effect of CBD. This study validated the effects of CBD on sleep and evaluated its potential therapeutic effects on insomnia.