Abstract (1) Background: In addition to the major phytocannabinoids, trans-Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD), the cannabis plant (Cannabis sativa L.) synthesizes over 120 additional cannabinoids that are known as minor cannabinoids. These minor cannabinoids have been proposed to act as agonists and antagonists at numerous targets including cannabinoid type 1 (CB1) and type 2 (CB2) receptors, transient receptor potential (TRP) channels and others. The goal of the present study was to determine the agonist effects of the minor cannabinoids: cannabinol (CBN), cannabigerol (CBG), cannabichromene (CBC), cannabitriol (CBT) and cannabidivarin (CBDV) at the CB1 receptor. In addition, the CB1 receptor antagonist effects of Δ9-tetrahydrocannabivarin (Δ9-THCV) were compared with its...