Superoxide released from neutrophils causes a reduction in nitric oxide gas
| Autor: | Matthew B. Grisham, Keith Simpson, Ty W. Bryan, Patricia A. Jinkins, Michael W. Owens, Shawn A. Milligan, Richard A. Robbins, Kimberly L. Jones, Boaz A. Markewitz |
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| Rok vydání: | 1998 |
| Předmět: |
Pulmonary and Respiratory Medicine
Cell Survival Neutrophils Physiology Nitric Oxide Synthase Type II Pharmacology Nitric Oxide Cystic fibrosis Cell Line Nitric oxide Mice chemistry.chemical_compound Superoxides Physiology (medical) medicine Animals Humans RNA Messenger Respiratory system Lung Nitrates biology Superoxide Respiratory disease Epithelial Cells Cell Biology Hydrogen-Ion Concentration Oxidants medicine.disease Nitric oxide synthase medicine.anatomical_structure chemistry Immunology Exhaled nitric oxide biology.protein Tyrosine Gases Nitric Oxide Synthase |
| Zdroj: | American Journal of Physiology-Lung Cellular and Molecular Physiology. 275:L1120-L1126 |
| ISSN: | 1522-1504 1040-0605 |
| DOI: | 10.1152/ajplung.1998.275.6.l1120 |
| Popis: | Exhaled nitric oxide (NO) is increased in some inflammatory airway disorders but not in others such as cystic fibrosis and acute respiratory distress syndrome. NO can combine with superoxide ([Formula: see text]) to form peroxynitrite, which can decompose into nitrate. Activated polymorphonuclear neutrophils (PMNs) releasing[Formula: see text] could account for a reduction in exhaled NO in disorders such as cystic fibrosis. To test this hypothesis in vitro, we stimulated confluent cultures of LA-4 cells, a murine lung epithelial cell line, to produce NO. Subsequently, human PMNs stimulated to produce [Formula: see text] were added to the LA-4 cells. A gradual increase in NO in the headspace above the cultures was observed and was markedly reduced by the addition of PMNs. An increase in nitrate in the culture supernatant fluids was measured, but no increase in nitrite was detected. Superoxide dismutase attenuated the PMN effect, and xanthine/xanthine oxidase reproduced the effect. No changes in epithelial cell inducible NO synthase protein or mRNA were observed. These data demonstrate that [Formula: see text]released from PMNs can decrease NO by conversion to nitrate and suggest a potential mechanism for modulation of NO levels in vivo. |
| Databáze: | OpenAIRE |
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