title: Mechanistic studies on AMD6221: a ruthenium-based nitric oxide scavenger.
abstract: Nitric oxide is a mediator of many disease states. Previous studies have demonstrated that ruthenium(III) polyaminocarboxylates can react with NO to form stable complexes reducing the levels of nitrite in the culture medium of stimulated RAW264 macrophages and reverse the NO-mediated hypotension in animal models of septic shock. It was necessary to confirm that these observations were due to NO scavenging and not inhibition of the NO metabolic pathway. Using RAW264 cells it was confirmed that [Ru(H(3)dtpa)(Cl)] (AMD6221) was neither acting at the level of iNOS induction, nor as an inhibitor of iNOS by measuring iNOS mRNA by RT-PCR and protein by Western blot and enzyme activity. Using HPLC, the nitrosyl adduct of reaction of AMD6221, [Ru(H(2)dtpa)NO], was identified in the medium of stimulated RAW264 cells co-incubated with AMD6221, concomitant with a stoichiometric reduction in nitrite/nitrate levels, thus confirming that the ruthenium(III) polyaminocarboxylates exert their pharmacological effect by scavenging NO.
authors.affiliation: AnorMED Inc., 200-20353 64th Avenue, Langley, British Columbia, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Mosi
authors.forename: B
authors.initials: B
authors.lastname: Seguin
authors.forename: B
authors.initials: B
authors.lastname: Cameron
authors.forename: L
authors.initials: L
authors.lastname: Amankwa
authors.forename: M C
authors.initials: MC
authors.lastname: Darkes
authors.forename: S P
authors.initials: SP
authors.lastname: Fricker
mesh_terms: D000818:Animals; D002460:Cell Line; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D009942:Organometallic Compounds / Q000737:chemistry / Q000494:pharmacology*; D004369:Pentetic Acid / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis; D017975:Ruthenium Compounds / Q000032:analysis
chemical_list: C453459:AMD 6221; D016166:Free Radical Scavengers; D009942:Organometallic Compounds; D012333:RNA, Messenger; D017975:Ruthenium Compounds; D009569:Nitric Oxide; D004369:Pentetic Acid; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse