Formation and stability of S-nitrosothiols in RAW 264.7 cells. Am J Physiol Lung Cell Mol Physiol 2004 Sep;287(3):L467-74
Date
12/16/2003Pubmed ID
14672925DOI
10.1152/ajplung.00350.2003Scopus ID
2-s2.0-4143071301 (requires institutional sign-in at Scopus site) 69 CitationsAbstract
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.
Author List
Zhang Y, Hogg NAuthor
Neil Hogg PhD Sr Associate Dean, Professor in the Biophysics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCell Line
Diffusion
Enzyme Inhibitors
Extracellular Space
Lipopolysaccharides
Luminescent Measurements
Macrophages
NG-Nitroarginine Methyl Ester
Nitric Oxide
Nitric Oxide Synthase
Nitrosation
Oxyhemoglobins
S-Nitrosothiols
