|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
EDITORIAL FOCUS
Department of Biophysics and Free Radical Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
Submitted 1 October 2003 ; accepted in final form 7 December 2003
S-Nitrosothiols have been suggested to be mediators of many nitric oxide-dependent processes, including apoptosis and vascular relaxation. Thiol nitrosation is a poorly understood process in vivo, and the mechanisms by which nitric oxide can be converted into a nitrosating agent have not been established. There is a discrepancy between the suggested biological roles of nitric oxide and its known chemical and physical properties. In this study, we have examined the formation of S-nitrosothiols in lipopolysaccharide-treated RAW 264.7 cells. This treatment generated 17.4 ± 1.0 pmol/mg of protein (means ± SE, n =27) of intracellular S-nitrosothiol that slowly decayed over several hours. S-Nitrosothiol formation depended on the formation of nitric oxide and not on the presence of nitrite. Extracellular thiols were nitrosated by cell-generated nitric oxide. Oxygenated ferrous hemoglobin inhibited the formation of S-nitrosothiol, indicating the nitrosation occurred more slowly than diffusion. We discuss several mechanisms for S-nitrosothiol formation and conclude that the nitrosation propensity of nitric oxide is a freely diffusible element that is not constrained within an individual cell and that both nitric oxide per se and nitric oxide-derived nitrosating agents are able to diffuse across cell membranes. To achieve intracellular localization of the nitrosation reaction, mechanisms must be invoked that do not involve the formation of nitric oxide as an intermediate.
nitric oxide; nitrosation; nitric oxide synthase; lipopolysaccharide; hemoglobin
This article has been cited by other articles:
![]() |
J. R. Laver, T. M. Stevanin, S. L. Messenger, A. D. Lunn, M. E. Lee, J. W. B. Moir, R. K. Poole, and R. C. Read Bacterial nitric oxide detoxification prevents host cell S-nitrosothiol formation: a novel mechanism of bacterial pathogenesis FASEB J, January 1, 2010; 24(1): 286 - 295. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Carraro, J. Doherty, K. Zaman, I. Gainov, R. Turner, J. Vaughan, J. F. Hunt, J. Marquez, and B. Gaston S-nitrosothiols regulate cell-surface pH buffering by airway epithelial cells during the human immune response to rhinovirus Am J Physiol Lung Cell Mol Physiol, May 1, 2006; 290(5): L827 - L832. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Tunbridge, T. M. Stevanin, M. Lee, H. M. Marriott, J. W. B. Moir, R. C. Read, and D. H. Dockrell Inhibition of Macrophage Apoptosis by Neisseria meningitidis Requires Nitric Oxide Detoxification Mechanisms Infect. Immun., January 1, 2006; 74(1): 729 - 733. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Lancaster Jr. and B. Gaston NO and nitrosothiols: spatial confinement and free diffusion Am J Physiol Lung Cell Mol Physiol, September 1, 2004; 287(3): L465 - L466. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |