title: Effect of .OH scavenging action by non-SH-containing angiotensin converting enzyme inhibitor imidaprilat using microdialysis.
abstract: We examined the effect of non-SH-containing angiotensin converting enzyme (ACE) inhibitor imidaprilat on hydroxyl radical (.OH) generation using microdialysis. Salicylic acid in Ringer's solution containing sodium salicylate (0.5 n mol microL-1 min-1) was infused directly through a microdialysis probe to detect the generation of .OH as reflected by the formation of 2,3-dihydroxybenzoic acid (DHBA) in the myocardium of anesthetized rats. We compared the ability of two non-SH-containing ACE inhibitors (imidaprilat and enalaprilat) with an -SH-containing ACE inhibitor (captopril) to scavenge the .OH. When iron (II) was administered to animals pretreated with these three ACE inhibitors, a decrease in 2,3-DHBA of all three compounds was observed, as compared with the iron (II) only-treated group. All three ACE inhibitors were able to scavenge .OH generated by the action of iron (II). However, imidaprilat is a free radical scavenger more potent than enalaprilat. These results suggested that ACE inhibitors are probably not only related to the presence of the SH radical.
authors.affiliation: Department of Pharmacology, Oita Medical University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Obata
authors.forename: Y
authors.initials: Y
authors.lastname: Yamanaka
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D000818:Animals; D015773:Enalaprilat / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000494:pharmacology*; D017665:Hydroxyl Radical; D007093:Imidazoles / Q000494:pharmacology*; D048289:Imidazolidines; D008297:Male; D017551:Microdialysis; D015394:Molecular Structure; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D016166:Free Radical Scavengers; D007093:Imidazoles; D048289:Imidazolidines; D017665:Hydroxyl Radical; D015773:Enalaprilat; C078006:imidaprilat