Δ⁹-Tetrahydrocannabinol-like discriminative stimulus effects of five novel synthetic cannabinoids in rats

Novel synthetic cannabinoid compounds continue to appear in the market advertised as legal alternatives to marijuana and the older synthetic cannabinoid compounds which are now controlled substances. Most of these newer compounds have been found to act at CB1 receptors, so the purpose of this study was to study the abuse liability of these compounds.

Five of these compounds (BB-22, FUB-PB-22, 5F-AMB, NM2201, and MAB-CHMINACA) were tested for their ability to produce discriminative stimulus effects similar to Δ⁹-tetrahydrocannabinol (Δ⁹-THC) in rats. The ability of the CB1 receptor inverse agonist rimonabant to antagonize the discriminative stimulus effects of the five test compounds was also tested.

All five of the test compounds fully substituted for the discriminative stimulus effects of Δ⁹-THC at some dose, although MAB-CHMINACA produced an inverted U-shaped dose effect. Rimonabant fully antagonized the Δ⁹-THC-like discriminative stimulus effects of BB-22, 5F-AMB, NM2201, and MAB-CHMINACA but only reduced the effects of FUB-PB-22 to 40-50 % of Δ⁹-THC-appropriate responding.

These findings suggest that all five of the test compounds produced Δ⁹-THC-like effects and will likely have abuse liability similar to that of the controlled cannabinoid compounds.