Background: Cannabidiol, a therapeutic with potential serotonin (5-hydroxytryptamine; 5-HT) 5- HT1A receptor agonist activity, is the second most prevalent cannabinoid in Cannabis after 9 - THC. The extent to which cannabidiol modifies the effects of 9 -THC has not been firmly established, especially with respect to abuse-related effects in rhesus monkeys where previously antagonistic interactions have been reported for some behavioral outcomes. Methods: Cannabidiol and the 5-HT1A receptor agonist (±)-8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OHDPAT) were tested in two separate discrimination assays in rhesus monkeys. One group (n=6) discriminated 9 -tetrahydrocannabinol ( 9 -THC; 0.1 mg/kg i.v.); a second group (n=6) discriminated the cannabinoid...
