title: Phorbol ester-induced release of endothelium-derived relaxing factor.
abstract: The effects of a phorbol ester, 12-deoxyphorbol 13-isobutyrate (DPB), on contraction of isolated vascular smooth muscle of rat aorta were examined. DPB (100 nM-1 microM) induced a concentration-dependent contraction in resting aorta. DPB (3-100 nM) also induced a concentration-dependent relaxation of the norepinephrine-induced contraction. The contractile effect of DPB was potentiated whereas the relaxant effect was inhibited by endothelium removal or by methylene blue, suggesting that lower concentrations of DPB release endothelium-derived relaxing factor to inhibit contraction in rat aorta.
authors.affiliation: Department of Veterinary Pharmacology, Faculty of Agriculture, University of Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sakata
authors.forename: H
authors.initials: H
authors.lastname: Karaki
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic; D002217:Carbachol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010703:Phorbol Esters / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D010703:Phorbol Esters; C039067:12-deoxyphorbol 13-isobutyrate; D009569:Nitric Oxide; D002217:Carbachol; D009638:Norepinephrine