Cannabidiol decreases body weight gain in rats: involvement of CB2 receptors.

Cannabidiol (CBD) is a major non-psychotropic constituent of Cannabis sativa, with well recognized therapeutic potential. Considering the importance of the endogenous cannabinoid system to the regulation of food intake and energy balance we studied the effects of repeated CBD administration on body weight gains in rats. Male Wistar rats (260 ± 20 g at start of study) received intraperitoneal injections of CBD at doses of 2.5 and 5mg/kg/day for 14 consecutive days and body weight gains were monitored. Both doses of CBD produced significant decrease in body weight gain, with the effect produced by 5mg/kg being more pronounced. The CB2 receptor selective antagonist, AM630, blocked the decrease in body weight gain. AM630 alone did not affect body weight gain. The results suggest that CBD has the ability to alter body weight gain, possibly via the CB2 receptor. CB2 receptors may play a role in the regulation of body weight and the effects of CB2 specific ligands should be further investigated in studies of body weight regulation.