Changes in xanthine oxidase in ischemic rat brain

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✓ Xanthine oxidase activity in the rat brain was measured by means of high-performance liquid chromatography with electrochemical detection of uric acid. Cerebral ischemia was produced by a four-vessel occlusion method. In the control rat, the enzyme activity was 0.87 ± 0.13 nmol/gm wet weight/min at 25°C (mean ± standard deviation), of which 92.4% was associated with the nicotinamide adenine dinucleotide (NAD)-dependent dehydrogenase form and only 7.6% with the oxygen-dependent superoxide-producing oxidase form. However, the ratio of the latter form increased to 43.7% after 30 minutes of global ischemia, despite the total xanthine oxidase activity remaining the same. Thus, it was revealed that uric acid can be synthesized in the rat brain and that cerebral ischemia induced the conversion of xanthine oxidase from an NAD-dependent dehydrogenase to an oxygen-dependent superoxide-producing oxidase. Although the xanthine oxidase pathway has been proposed as a source of oxygen-derived free radicals in various ischemic organs other than brain, the results of the present study suggest the involvement of the oxygen free radicals generated from this pathway in the pathogenesis of the ischemic injury of the rat brain.

Article Information

Address reprint requests to: Yuji Kinuta, M.D., Ph.D., Department of Neurosurgery, Faculty of Medicine, Kyoto University, 54 Kawaracho, Shougoin, Sakyo-ku, Kyoto 606, Japan.

© AANS, except where prohibited by US copyright law.

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Figures

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    Xanthine oxidase in purine metabolism of the rat brain. Xanthine oxidase consists of the nicotinamide adenine dinucleotide (NAD)-dependent dehydrogenase (Type D) and the oxygen-dependent superoxide-producing oxidase (Type O). ATP = adenosine triphosphate; NADH = NAD, reduced form.

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    Examples of urate production at different incubation times. A value of urate production in the reaction mixture with nicotinamide adenine dinucleotide (NAD) means the activity of Type D plus Type O. A value in the reaction mixture without NAD means the activity of Type O. Note the difference in urate production rate between the control and ischemic rat brains in the reaction mixture without NAD.

References

  • 1.

    Al-Khalidi URSChaglassian TH: The species distribution of xanthine oxidase. Biochem J 97:3183201965Al-Khalidi URS Chaglassian TH: The species distribution of xanthine oxidase. Biochem J 97:318–320 1965

    • Search Google Scholar
    • Export Citation
  • 2.

    Betz AL: Identification of hypoxanthine transport and xanthine oxidase activity in brain capillaries. J Neurochem 44:5745791985Betz AL: Identification of hypoxanthine transport and xanthine oxidase activity in brain capillaries. J Neurochem 44:574–579 1985

    • Search Google Scholar
    • Export Citation
  • 3.

    Chan PHSchmidley JWFishman RAet al: Brain injury, edema, and vascular permeability changes induced by oxygen-derived free radicals. Neurology 34:3153201984Chan PH Schmidley JW Fishman RA et al: Brain injury edema and vascular permeability changes induced by oxygen-derived free radicals. Neurology 34:315–320 1984

    • Search Google Scholar
    • Export Citation
  • 4.

    Della Corte EStirpe F: The regulation of rat liver xanthine oxidase. Biochem J 126:7397451972Della Corte E Stirpe F: The regulation of rat liver xanthine oxidase. Biochem J 126:739–745 1972

    • Search Google Scholar
    • Export Citation
  • 5.

    Del Maestro RFBjork JArfors KE: Increase in microvascular permeability induced by enzymatically generated free radicals. Microvasc Res 22:2392541981Del Maestro RF Bjork J Arfors KE: Increase in microvascular permeability induced by enzymatically generated free radicals. Microvasc Res 22:239–254 1981

    • Search Google Scholar
    • Export Citation
  • 6.

    Downey JMMiura TEddy LJet al: Xanthine oxidase is not a source of free radicals in the ischemic rabbit heart. J Mol Cell Cardiol 19:105310601987Downey JM Miura T Eddy LJ et al: Xanthine oxidase is not a source of free radicals in the ischemic rabbit heart. J Mol Cell Cardiol 19:1053–1060 1987

    • Search Google Scholar
    • Export Citation
  • 7.

    Jarasch EDBruder GHeid HW: Significance of xanthine oxidase in capillary endothelial cells. Acta Physiol Scand Suppl 548:39461986Jarasch ED Bruder G Heid HW: Significance of xanthine oxidase in capillary endothelial cells. Acta Physiol Scand Suppl 548:39–46 1986

    • Search Google Scholar
    • Export Citation
  • 8.

    Kanemitsu HTamura ASano Ket al: Changes of uric acid level in rat brain after focal ischemia. J Neurochem 46:8518531986Kanemitsu H Tamura A Sano K et al: Changes of uric acid level in rat brain after focal ischemia. J Neurochem 46:851–853 1986

    • Search Google Scholar
    • Export Citation
  • 9.

    Markley HGFaillace LAMezey E: Xanthine oxidase activity in rat brain. Biochim Biophys Acta 309:23311973Markley HG Faillace LA Mezey E: Xanthine oxidase activity in rat brain. Biochim Biophys Acta 309:23–31 1973

    • Search Google Scholar
    • Export Citation
  • 10.

    McCord JM: Oxygen-derived free radicals in postischemic tissue injury. N Engl J Med 312:1591631985McCord JM: Oxygen-derived free radicals in postischemic tissue injury. N Engl J Med 312:159–163 1985

    • Search Google Scholar
    • Export Citation
  • 11.

    Onodera HIijima KKogure K: Mononucleotide metabolism in the rat brain after transient ischemia. J Neurochem 46:170417101986Onodera H Iijima K Kogure K: Mononucleotide metabolism in the rat brain after transient ischemia. J Neurochem 46:1704–1710 1986

    • Search Google Scholar
    • Export Citation
  • 12.

    Parks DAGranger DN: Xanthine oxidase: biochemistry, distribution and physiology. Acta Physiol Scand Suppl 548:87991986Parks DA Granger DN: Xanthine oxidase: biochemistry distribution and physiology. Acta Physiol Scand Suppl 548:87–99 1986

    • Search Google Scholar
    • Export Citation
  • 13.

    Podzuweit TBraun WMuller Aet al: Arrhythmias and infarction in the ischemic pig heart are not mediated by xanthine oxidase-derived free oxygen radicals. Basic Res Cardiol 82:4935051987Podzuweit T Braun W Muller A et al: Arrhythmias and infarction in the ischemic pig heart are not mediated by xanthine oxidase-derived free oxygen radicals. Basic Res Cardiol 82:493–505 1987

    • Search Google Scholar
    • Export Citation
  • 14.

    Ponten URatcheson RASalford LGet al: Optimal freezing conditions for cerebral metabolites in rats. J Neurochem 21:112711381973Ponten U Ratcheson RA Salford LG et al: Optimal freezing conditions for cerebral metabolites in rats. J Neurochem 21:1127–1138 1973

    • Search Google Scholar
    • Export Citation
  • 15.

    Pulsinelli WABrierley JB: A new model of bilateral hemispheric ischemia in the unanesthetized rat. Stroke 10:2672721979Pulsinelli WA Brierley JB: A new model of bilateral hemispheric ischemia in the unanesthetized rat. Stroke 10:267–272 1979

    • Search Google Scholar
    • Export Citation
  • 16.

    Ramboer CRH: A sensitive and nonradioactive assay for serum and tissue xanthine oxidase. J Lab Clin Med 74:8288351969Ramboer CRH: A sensitive and nonradioactive assay for serum and tissue xanthine oxidase. J Lab Clin Med 74:828–835 1969

    • Search Google Scholar
    • Export Citation
  • 17.

    Santos JNHempstead KWKopp LEet al: Nucleotide metabolism in rat brain. J Neurochem 15:3673761968Santos JN Hempstead KW Kopp LE et al: Nucleotide metabolism in rat brain. J Neurochem 15:367–376 1968

    • Search Google Scholar
    • Export Citation
  • 18.

    Schultz VLowenstein JM: Purine nucleotide cycle: evidence for the occurrence of the cycle in brain. J Biol Chem 251:4854921976Schultz V Lowenstein JM: Purine nucleotide cycle: evidence for the occurrence of the cycle in brain. J Biol Chem 251:485–492 1976

    • Search Google Scholar
    • Export Citation
  • 19.

    Spector R: Hypoxanthine transport and metabolism in the central nervous system. J Neurochem 50:9699781988Spector R: Hypoxanthine transport and metabolism in the central nervous system. J Neurochem 50:969–978 1988

    • Search Google Scholar
    • Export Citation
  • 20.

    Stirpe FDella Corte E: The regulation of rat liver xanthine oxidase. J Biol Chem 244:385538631969Stirpe F Della Corte E: The regulation of rat liver xanthine oxidase. J Biol Chem 244:3855–3863 1969

    • Search Google Scholar
    • Export Citation
  • 21.

    Villela GG: Xanthine oxidase activity in the brain. Experientia 24:110111021968Villela GG: Xanthine oxidase activity in the brain. Experientia 24:1101–1102 1968

    • Search Google Scholar
    • Export Citation
  • 22.

    Watson BDBusto RGoldberg WJet al: Lipid peroxidation in vivo induced by reversible global ischemia in rat brain. J Neurochem 42:2682741984Watson BD Busto R Goldberg WJ et al: Lipid peroxidation in vivo induced by reversible global ischemia in rat brain. J Neurochem 42:268–274 1984

    • Search Google Scholar
    • Export Citation

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