The G protein-coupled cannabinoid-1 (CB1) receptor of mammalian brain: Inhibition by phthalate esters in vitro

► Phthalate diesters inhibit [3H]CP-55940 and [3H]SR141716A binding to brain CB1-Rs. ► Phthalate monoesters are less effective inhibitors of [3H]radioligand binding. ► Inhibitory effects on G-protein activation and [3H]CP-55940 binding correlate well. ► Phthalates are low affinity, allosterically acting antagonists of CB1-R function.