Figure 3.
Cannabis vapor self-administration produces physiologically relevant cannabinoid concentrations and alterations in CB1R binding. Correlations between the number of cannabis vapor deliveries (200 or 400 mg/ml) earned and plasma concentrations of (A) THC (CANTHC-200: r = 0.51, p = 0.03; CANTHC-400: r = 0.86, p < 0.001) and (B) CBD (CANCBD-200: r = 0.58, p = 0.01; CANCBD-400: r = 0.51, p = 0.18) at the end of the 1 h self-administration session (n = 8–17/group). Brain tissue concentration of (C) THC and (D) CBD measured 24 h after the final self-administration session in rats trained to self-administer CANTHC or CANCBD vapor (n = 11/group). E, Hippocampal CB1R binding site density (pmol/mg protein) and (F) CB1R binding affinity (nm) in rats trained to self-administer CANTHC, CANCBD, or VEH. Tissue was analyzed 24 h after the final self-administration session. n = 4/group. p ≤ 0.05. *Significant differences between CANTHC and VEH groups. #Significant differences between CANTHC and CANCBD groups.