title: Overlap between the ligand recognition properties of the anandamide transporter and the VR1 vanilloid receptor: inhibitors of anandamide uptake with negligible capsaicin-like activity.
abstract: Some synthetic agonists of the VR1 vanilloid (capsaicin) receptor also inhibit the facilitated transport into cells of the endogenous cannabinoid anandamide (arachidonoylethanolamide, AEA). Here we tested several AEA derivatives containing various derivatized phenyl groups or different alkyl chains as either inhibitors of the AEA membrane transporter (AMT) in intact cells or functional agonists of the VR1 vanilloid receptor in HEK cells transfected with the human VR1. We found that four known AMT inhibitors, AM404, arvanil, olvanil and linvanil, activate VR1 receptors at concentrations 400-10000-fold lower than those necessary to inhibit the AMT. However, we also found three novel AEA derivatives, named VDM11, VDM12 and VDM13, which inhibit the AMT as potently as AM404 but exhibit little or no agonist activity at hVR1. These compounds are weak inhibitors of AEA enzymatic hydrolysis and poor CB(1)/CB(2) receptor ligands. We show for the first time that, despite the overlap between the chemical moieties of AMT inhibitors and VR1 agonists, selective inhibitors of AEA uptake that do not activate VR1 (e.g. VDM11) can be developed.
authors.affiliation: Endocannabinoid Research Group, Istituto di Cibernetica, C.N.R. Via Toiano 6, 80072, Arco Felice, Napoli, Italy.
authors.forename: L
authors.initials: L
authors.lastname: De Petrocellis
authors.forename: T
authors.initials: T
authors.lastname: Bisogno
authors.forename: J B
authors.initials: JB
authors.lastname: Davis
authors.forename: R G
authors.initials: RG
authors.lastname: Pertwee
authors.forename: V
authors.initials: V
authors.lastname: Di Marzo
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D001667:Binding, Competitive / Q000187:drug effects; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002211:Capsaicin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D063388:Endocannabinoids; D006801:Humans; D008024:Ligands; D053284:Polyunsaturated Alkamides; D051381:Rats; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism*; D050916:TRPV Cation Channels; D014407:Tumor Cells, Cultured
chemical_list: D001095:Arachidonic Acids; D063388:Endocannabinoids; D008024:Ligands; D053284:Polyunsaturated Alkamides; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug; D050916:TRPV Cation Channels; C494484:TRPV1 receptor; C121153:arvanil; D002211:Capsaicin; D002118:Calcium; C078814:anandamide; C107594:N-(4-hydroxyphenyl)arachidonylamide