Nitric oxide: a cytotoxic activated macrophage effector molecule

Biochem Biophys Res Commun. 1988 Nov 30;157(1):87-94. doi: 10.1016/s0006-291x(88)80015-9.


The experiments reported here identify nitric oxide as a molecular effector of activated macrophage induced cytotoxicity. Cytotoxic activated macrophages synthesize nitric oxide from a terminal guanidino nitrogen atom of L-arginine which is converted to L-citrulline without loss of the guanidino carbon atom. In addition, authentic nitric oxide gas causes the same pattern of cytotoxicity in L10 hepatoma cells as is induced by cytotoxic activated macrophages (iron loss as well as inhibition of DNA synthesis, mitochondrial respiration, and aconitase activity). The results suggest that nitric oxide is the precursor of nitrite/nitrate synthesized by cytotoxic activated macrophages and, via formation of iron-nitric oxide complexes and subsequent degradation of iron-sulfur prosthetic groups, an effector molecule.

Publication types

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

MeSH terms

  • Animals
  • Arginine / physiology
  • Cell Survival
  • Cricetinae
  • Hydrogen-Ion Concentration
  • Macrophage Activation
  • Macrophages / physiology*
  • Nitric Oxide / physiology*
  • Nitrogen Dioxide / physiology
  • Tumor Cells, Cultured


  • Nitric Oxide
  • Arginine
  • Nitrogen Dioxide