Effect of hydrogen peroxide and catalase on rat cerebellum nitric oxide synthase

Biochem Pharmacol. 1994 Jul 19;48(2):423-5. doi: 10.1016/0006-2952(94)90116-3.

Abstract

The effect of H2O2 and catalase on isolated rat cerebellum nitric oxide (NO) synthase activity was determined by measuring the conversion of L-[3H]arginine to L-[3H]citrulline. H2O2 (1-5 mM) markedly increased NO synthase activity in the presence of endogenous catalase (72 +/- 4 U/mL). This effect of H2O2 was further increased by exogenous catalase (200 U/mL). Exogenous catalase (0.1 to 1000 U/mL) by itself had no significant effect on NO synthase activity. Nitroblue tetrazolium chloride, an electron acceptor, inhibited NO synthase activity in a concentration-dependent manner. This study suggests that H2O2 is not directly involved in NO synthesis and that the H2O2/catalase stimulation of NO synthase activity may be due to the excess oxygen produced by the H2O2/catalase system.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Oxidoreductases / antagonists & inhibitors
  • Amino Acid Oxidoreductases / metabolism*
  • Animals
  • Arginine / metabolism
  • Catalase / pharmacology*
  • Cerebellum / drug effects*
  • Cerebellum / enzymology
  • Citrulline / metabolism
  • Hydrogen Peroxide / pharmacology*
  • In Vitro Techniques
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase
  • Rats
  • Tetrazolium Salts / pharmacology

Substances

  • Tetrazolium Salts
  • 4-anisyltetrazolium blue
  • Citrulline
  • Nitric Oxide
  • Arginine
  • Hydrogen Peroxide
  • Catalase
  • Nitric Oxide Synthase
  • Amino Acid Oxidoreductases