title: Imidaprilat suppresses nonylphenol and 1-methyl-4-phenylpyridinium ion (MPP+)-induced hydroxyl radical generation in rat striatum.
abstract: The present study examined the antioxidant effects of angiotensin-converting enzyme inhibitor (ACE), imidaprilat, on para-nonylphenol and 1-methyl-4-phenylpyridinium ion (MPP+)-induced hydroxyl radical (*OH) formation and dopamine (DA) efflux in extracellular fluid of rat striatum, using a microdialysis technique. para-Nonylphenol clearly enhanced *OH formation and DA efflux induced by MPP+. When imidaprilat was infused in para-nonylphenol and MPP+-treated rats, DA efflux and *OH formation significantly decreased, as compared with that in the para-nonylphenol and MPP+-treated control. Imidaprilat was able to scavenge *OH and DA efflux induced by para-nonylphenol and MPP+. When iron(II) was administered to para-nonylphenol-pretreated animals, iron(II) clearly produced a dose-dependent increase in the levels of 2,3-dihydroxybenzoic acid (2,3-DHBA), as compared with MPP+-only-treated rats. A positive linear correlation was observed between iron(II) and 2,3-DHBA (R2=0.985) in the dialysate. However, in the presence of imidaprilat, a small increase in the levels of 2,3-DHBA products was observed. The results suggest that imidaprilat may protect against para-nonylphenol and MPP+-induced *OH formation via suppressing DA efflux in the rat striatum.
authors.affiliation: Department of Analytical Chemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611, Japan. t-obata@pha.ohu-u.ac.jp
authors.forename: Toshio
authors.initials: T
authors.lastname: Obata
mesh_terms: D015655:1-Methyl-4-phenylpyridinium / Q000008:administration & dosage*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage*; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D045604:Extracellular Fluid / Q000737:chemistry / Q000187:drug effects; D017665:Hydroxyl Radical / Q000378:metabolism*; D048289:Imidazolidines / Q000008:administration & dosage*; D008297:Male; D017551:Microdialysis; D010636:Phenols / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D048289:Imidazolidines; D010636:Phenols; D017665:Hydroxyl Radical; C025256:nonylphenol; D015655:1-Methyl-4-phenylpyridinium; D004298:Dopamine; C078006:imidaprilat