2-Arachidonoyl glycerol (2-AG) has been isolated from porcine brain, and has been characterized as the natural endocannabinoid ligand for the CB1 receptor. The congener of 2-AG in which a linoleoyl group replaces the arachidonoyl group is 2-linoleoyl glycerol (2-LG), and this compound also appears in vivo in conjunction with 2-AG. Although the intrinsic activity of 2-LG is low, it potentiates the activity of other endocannabinoids, including 2-AG. This “entourage” effect has been attributed to blockade of the breakdown and reuptake pathways that normally function to reduce endocannabinoid levels rapidly upon release.
