The endocannabinoid system is implicated in a variety of physiological and pathological conditions (inflammation, immunomodulation, analgesia, cancer and others). The main active ingredient of cannabis, D9 -tetrahydrocannabinol (D9 -THC), produces its effects through activation of CB1 and CB2 receptors. CB1 receptors are expressed at high levels in the central nervous system (CNS), whereas CB2 receptors are concentrated predominantly, although not exclusively, in cells of the immune system. Endocannabinoids are endogenous lipid-signalling molecules that are generated in the cell membrane from phospholipid precursors. The two best characterized endocannabinoids identified to date are anandamide (AEA) and 2-arachidonoylglycerol (2-AG). Here we review the relationship between the endocannabinoid...
