title: Tetrahydrobiopterin-dependent formation of endothelium-derived relaxing factor (nitric oxide) in aortic endothelial cells.
abstract: Inhibition of tetrahydrobiopterin (H4biopterin) biosynthesis in endothelial cells almost completely abolished the agonist-induced formation of endothelium-derived relaxing factor (EDRF) (NO). This inhibitory effect could be antagonized when H4biopterin biosynthesis was restored by activating a salvage pathway. These data indicate that the formation of EDRF strictly depends on the presence of intracellular H4biopterin, which, in addition to Ca2+, may represent a further physiological and/or pathophysiological regulatory of endothelial NO synthases.
authors.affiliation: Institut für Pharmakodynamik und Toxikologie, Universität Graz, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Schmidt
authors.forename: E R
authors.initials: ER
authors.lastname: Werner
authors.forename: B
authors.initials: B
authors.lastname: Mayer
authors.forename: H
authors.initials: H
authors.lastname: Wachter
authors.forename: W R
authors.initials: WR
authors.lastname: Kukovetz
mesh_terms: D000818:Animals; D001011:Aorta; D001708:Biopterins / Q000031:analogs & derivatives* / Q000494:pharmacology; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D007042:Hypoxanthines / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis* / Q000378:metabolism; D013552:Swine
chemical_list: D007042:Hypoxanthines; D001708:Biopterins; D009569:Nitric Oxide; C017202:2,4-diaminohypoxanthine; C003402:sapropterin