O-1918 is a cannabidiol analog and a selective antagonist at the endothelial cannabidiol receptor. It is an inhibitor of GPR18. O-1918 can also induce endothelium-dependent vasodilation.
Selective, silent antagonist of a putative endothelial anandamide receptor distinct from CB 1 or CB 2 receptors. Inhibits vasodilation and cell migration induced by abnormal-cannabidiol (abn-CBD; 4-[(1R,6R)-3-Methyl-6-(1-methylethenyl)-2-cyclohexen-1-yl]-5-pentyl-1,3-benzenediol).
This endocannabinoid antagonist (FW = 286.42 g/mol; CAS 536697-79-7), systematically named 1,3-dimethoxy-5-methyl-2-[(1R,6R)-3-methyl-6-(1- methylethenyl)-2-cyclohexen-1-yl]benzene, is a cannabidinodiol analogue that selectively targets a putative G-coupled endothelial anandamide receptor that is distinct from CB1 or CB2 endocannabinoid receptors. O- 1918 does not bind to CB1 or CB2 receptors and does not cause vasorelaxation at concentrations up to 30 μM, but inhibits the vasorelaxant effects of abn-cbd and anandamide in a concentration-dependent manner (1- 30 μM). (See abn-cbd; Anandamide; Oleamide). While the atypical cannabinoids O-1602 and abn-cbd (or abnormal cannabidiol) stimulate GPR55-dependent GTPgS activity (EC50 ~ 2 nM), O-1918 antagonizes such effects. O-1918 is involved in the delayed hypotension induced by anandamide in anaesthetized rats.
