Cannabinoid CB1 receptors control conditioned drug seeking

Recent developments have implicated cannabinoid CB, receptors as a novel target for a new class of therapeutic agents used to treat drug addiction. CB, receptors are expressed in the motivational circuitry of the brain and modulate drug seeking. Blockade of the CB, receptor is particularly effective in reducing cue-induced reinstatement of drug seeking, an animal analogue of cue-induced relapse in human addicts. These relapse-preventing properties are observed with different classes of abused drug (i.e. psychostimulants, opiates, nicotine and alcohol). In addition, recent evidence indicates a more general role of CB, receptors in reward-related memories, which is consistent with the proposed role of endocannabinoids in memory-related plasticity. Relapse-preventing actions and inhibitory effects on weight gain were confirmed recently in clinical trials with the CB, antagonist rimonabant. Collectively, these clinical and preclinical studies suggest that antagonists of CB, receptors offer a novel approach in the treatment of addictive behaviours.