Figure 10: Terpenes act as A_2AR agonists in vitro.

A_2AR-HEK cells used for each experiment. Data represented as the mean ± SEM, with the sample size of independent experiments shown in each graph. Experiments performed in 3–4 technical, independent replicates. A) Vehicle, terpenes (100 µM), and NECA positive control (10 µM) used to stimulate cAMP accumulation. Data normalized to the percent stimulation caused by vehicle (0%) and NECA (100%). **** = p < 0.0001 vs. vehicle group by 1 Way ANOVA with Dunnett’s post hoc test. B) Competition radioligand binding performed with terpene (300 µM) competing against the orthosteric A_2AR ligand ³H-ZM241385. Data normalized to the percent competition caused by vehicle (0%) and saturating cold ligand (100%). Together the results suggest that terpenes act as A_2AR partial agonists without competing against the orthosteric ligand ZM241385.