“The cannabinoid signaling system includes two G protein coupled receptors, CB1 and CB2. These receptors are widely distributed throughout the body and have each been implicated in many physiologically important processes.
Though the cannabinoid signaling system has therapeutic potential, a persistent hurdle has remained the development of receptor-selective ligands. Because CB1 and CB2 are involved in diverse processes, it would be advantageous develop ligands that differentially engaging CB1 and CB2.
In summary we have determined that GW405833 and AM1710 are not only CB2 agonists but also CB1 antagonists, with distinctive and complex signaling properties. Thus experiments using these compounds must take into account their potential activity at CB1 receptors.”