title: Effects of a calcium-channel blocker (CV159) on hepatic ischemia/reperfusion injury in rats: evaluation with selective NO/pO2 electrodes and an electron paramagnetic resonance spin-trapping method.
abstract: Nitric oxide (NO) and the partial pressure of oxygen (pO(2)) in the liver were simultaneously quantified in rats with partial hepatic ischemia/reperfusion injury (PHIRI). Real-time NO/pO(2) monitoring and immunohistochemical analysis for superoxide dismutase and inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) were performed to evaluate the protective effects of a dihydropyridine-type calcium-channel blocker--CV159--on PHIRI. Serum high-mobility-group box-1 (HMGB-1) was measured to assess cellular necrosis. Moreover, we used in vitro/ex vivo electron paramagnetic resonance spin trapping to assess the hydroxyl radical (*OH)-scavenging activity (OHSA) of CV159 and the liver tissue. The NO levels were significantly higher in CV159-treated rats than in control rats throughout the ischemic phase. Immediately after reperfusion, the levels temporarily increased in waves and then gradually decreased in the treated rats but remained constant in the control rats. pO(2) was continually higher in the treated rats. In these rats, hepatic eNOS expression increased, whereas iNOS expression decreased. The treated rats exhibited significantly higher cytosolic and mitochondrial concentrations NOx (NO(2)+NO(3)). The serum HMGB-1 levels significantly decreased in the treated rats. Moreover, CV159 directly scavenged *OH and both mitochondrial and cytosolic OHSA were preserved in the treated rats. Thus, CV159-mediated inhibition of intracellular Ca(2+) overloading may effectively minimize organ damage and also have *OH-scavenging activity and the cytoprotective effects of eNOS-derived NO.
authors.affiliation: Department of Gastroenterological and General Surgery, St. Marianna University Hospital, Kawasaki, Japan.
authors.forename: Keizo
authors.initials: K
authors.lastname: Hataji
authors.forename: Taiji
authors.initials: T
authors.lastname: Watanabe
authors.forename: Shigeru
authors.initials: S
authors.lastname: Oowada
authors.forename: Masaki
authors.initials: M
authors.lastname: Nagaya
authors.forename: Masato
authors.initials: M
authors.lastname: Kamibayashi
authors.forename: Eiichi
authors.initials: E
authors.lastname: Murakami
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Kawakami
authors.forename: Atsuko
authors.initials: A
authors.lastname: Ishiuchi
authors.forename: Toshio
authors.initials: T
authors.lastname: Kumai
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakano
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Takehito
authors.initials: T
authors.lastname: Otsubo
mesh_terms: D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology / Q000627:therapeutic use*; D003600:Cytosol / Q000378:metabolism; D004095:Dihydropyridines / Q000494:pharmacology / Q000627:therapeutic use*; D004566:Electrodes; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D004727:Endothelium / Q000378:metabolism; D016166:Free Radical Scavengers / Q000494:pharmacology / Q000627:therapeutic use; D024243:HMGB1 Protein / Q000097:blood; D017665:Hydroxyl Radical; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D009336:Necrosis / Q000378:metabolism / Q000517:prevention & control*; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009589:Nitrogen Oxides / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000517:prevention & control*
chemical_list: D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D016166:Free Radical Scavengers; D024243:HMGB1 Protein; D009589:Nitrogen Oxides; D009569:Nitric Oxide; D017665:Hydroxyl Radical; C055634:CV 159; D019001:Nitric Oxide Synthase; D010100:Oxygen