Cannabinoids (CBs) and their synthetic analogs produce biochemical and pharmacological effects by interacting with the central CB1 and peripheral CB2 receptors. The CB2 receptor has emerged as a pharmacotherapeutic target for treating osteoporosis, as well as for eliciting antinociceptive effects in various models of pain. 4-Quinolone-3-carboxamide CB2 ligand is a selective, high affinity ligand of the CB2 receptor, displaying a Ki value of 0.6 nM (Ki >10,000 nM for CB1) in vitro. At a dose of 6 mg/kg, 4-quinolone-3-carboxamide CB2 ligand exhibits antinociceptive activity in a formalin test of nocifensive response in mice. This analgesic affect is not significantly reversed by the CB2 antagonist AM630 , which suggests 4-quinolone-3-carboxamide CB2 ligand may behave as an inverse agonist.
