Nitric oxide protects nitric oxide synthase function from hydroxyl radical-induced inhibition

Biochim Biophys Acta. 2000 Aug 31;1481(1):156-66. doi: 10.1016/s0167-4838(00)00113-8.

Abstract

The interdependent relationships among nitric oxide synthase (NOS), its coenzyme, cofactors and nitric oxide (NO(free radical) were studied using electron paramagnetic resonance spectroscopy. It was found that superoxide-dependent hydroxyl free radical (OH(free radical), derived from NOS coenzyme and cofactors, inhibits NOS activity, and that endogenous NO(free radical) generated by NOS scavenges OH(free radical) and protects NOS function. These results reveal a new role for NO(free radical) that may be important in NOS function and cellular free radical homeostasis.

Publication types

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

MeSH terms

  • Coenzymes / metabolism
  • Electron Spin Resonance Spectroscopy
  • Free Radical Scavengers / pharmacology
  • Homeostasis
  • Hydroxyl Radical / analysis
  • Hydroxyl Radical / metabolism*
  • Nitric Oxide / metabolism*
  • Nitric Oxide / pharmacology
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase / metabolism*
  • Spin Trapping
  • Superoxides / metabolism

Substances

  • Coenzymes
  • Free Radical Scavengers
  • Superoxides
  • Nitric Oxide
  • Hydroxyl Radical
  • Nitric Oxide Synthase