An assessment of concurrent cannabidiol and Δ⁹-tetrahydrocannabinol administration in place aversion and taste avoidance conditioning.
Rising interest in medical marijuana has prompted research into its phytocannabinoid constituents, particularly Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). Coadministration of CBD with THC has been shown to modulate a number of THCs effects, including its negative stimulus properties (e.g., anxiety, paranoia, psychosis) in a clinical setting. The present series of experiments extended these analyses by examining the ability of CBD to impact the aversive effects of THC as assessed in a combined taste and place conditioning procedure. In Experiment 1, male and female Wistar rats were given access to a novel saccharin solution, injected with a vehicle solution CBD (0.075, 0.75 mgkg), THC (0.75 mgkg) or several combinations of CBD and THC (110 or 11 dose ratio), and then placed in a distinct chamber of a place conditioning apparatus. When THC was administered alone, it induced significant place aversions and taste avoidance. At both dose ratios, CBD failed to modulate either effect. There were no sex differences in either assay or at any ratio. A follow-up experiment (Experiment 2) employed identical dose ratios, but a higher dose of THC (7.5 mgkg) and corresponding CBD doses (0.75, 7.5 mgkg). Similar to the initial assessment, CBD had no effect on THC-induced place or taste conditioning at either dose ratio. These results may reflect the specific phytocannabinoid dose ratios examined or species differences in cannabinoid action. The current findings further suggest that altering CBD content in medicinal cannabis will likely have minimal effects in terms of tolerability. (PsycINFO Database Record