Protective effect of captopril and enalaprilat, angiotensin-converting enzyme inhibitors, on para-nonylphenol-induced *OH generation and dopamine efflux in rat striatum.
We recently reported that para-nonylphenol, an environmental chemical, induced hydroxyl radical (*OH) formation in rat striatum. In this study we examined the antioxidant effects of angiotensin-converting enzyme inhibitors (captopril or enalaprilat) on para-nonylphenol (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 captopril or enalaprilat was infused in nonylphenol and MPP(+)-treated rats, DA efflux and OH formation significantly decreased, as compared with that in the nonylphenol and MPP(+)-treated control. We compared the ability of non-SH-containing enalaprilat with a SH-containing captopril to scavenge OH and DA efflux. Both inhibitors were able to scavenge *OH and DA efflux induced by para-nonylphenol and MPP(+). The results suggest that angiotensin-converting enzyme inhibitors may protect against nonylphenol and MPP(+)-induced *OH formation via suppressing DA efflux in the rat striatum.
Obata
Toshio
T
Department of Analytical Chemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611, Japan. t-obata@pha.ohu-u.ac.jp
Takahashi
Shigehiro
S
Kashiwagi
Yoshitomo
Y
Kubota
Shunichiro
S
D015655:1-Methyl-4-phenylpyridinium / Q000633:toxicity; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D000818:Animals; D002216:Captopril / Q000494:pharmacology*; D002396:Catechols / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D015259:Dopamine Agents / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D015773:Enalaprilat / Q000494:pharmacology*; D062385:Hydroxybenzoates; D017665:Hydroxyl Radical / Q000378:metabolism*; D007501:Iron / Q000494:pharmacology; D008297:Male; D017072:Neostriatum / Q000187:drug effects / Q000378:metabolism*; D010636:Phenols / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar
D000806:Angiotensin-Converting Enzyme Inhibitors; D002396:Catechols; D015259:Dopamine Agents; D062385:Hydroxybenzoates; D010636:Phenols; D017665:Hydroxyl Radical; C009135:2,3-dihydroxybenzoic acid; D002216:Captopril; D007501:Iron; D015773:Enalaprilat; C041594:4-nonylphenol; D015655:1-Methyl-4-phenylpyridinium; D004298:Dopamine