TY - JOUR
T1 - Pulmonary alveolar epithelial inducible NO synthase gene expression
T2 - Regulation by inflammatory mediators
AU - Gutierrez, H. H.
AU - Pitt, B. R.
AU - Schwarz, M.
AU - Watkins, S. C.
AU - Lowenstein, C.
AU - Caniggia, I.
AU - Chumley, P.
AU - Freeman, B. A.
PY - 1995
Y1 - 1995
N2 - Nitric oxide (·NO) is a short-lived mediator that can be induced by different cytokines and lipopolysaccharide (LPS) in a variety of cell types and produces many physiological and metabolic changes in target cells. In the current study, we show that a combination of cytokines, LPS, and zymosan- activated serum (ZAS; called for convenience cytomix Z) induces production of high concentrations of the NO oxidation products nitrite (NO2/-) and nitrate (NO3/-) by cultured rat fetal lung epithelial type II cells in a time-dependent fashion. Interferon-γ and tumor necrosis factor-α alone did not significantly affect ·NO synthesis, whereas ZAS, LPS, and interleukin- 1β caused only a modest increase in formation of ·NO oxidation products. Production of NO2/- and NO3/- was inhibited by N(G)-monomethyl-L-arginine and cycloheximide. After exposure of these cells to a combination of the above cytokines, Escherichia coli LPS, and ZAS (cytomix Z), enhanced inducible nitric oxide synthase (iNOS) expression was indicated by an elevation in steady-state mRNA specific for iNOS (via Northern blot analysis) and increased immunofluorescence for iNOS after cell permeabilization, incubation with anti-iNOS antibody, and treatment with Cy3.18-conjugated rabbit-specific antibody. The extent of inflammatory mediator-induced ·NO production by alveolar epithelium, which exceeds that of other lung cell types, reveals new insight into mechanisms of pulmonary host defense and pathways of free radical-mediated lung injury.
AB - Nitric oxide (·NO) is a short-lived mediator that can be induced by different cytokines and lipopolysaccharide (LPS) in a variety of cell types and produces many physiological and metabolic changes in target cells. In the current study, we show that a combination of cytokines, LPS, and zymosan- activated serum (ZAS; called for convenience cytomix Z) induces production of high concentrations of the NO oxidation products nitrite (NO2/-) and nitrate (NO3/-) by cultured rat fetal lung epithelial type II cells in a time-dependent fashion. Interferon-γ and tumor necrosis factor-α alone did not significantly affect ·NO synthesis, whereas ZAS, LPS, and interleukin- 1β caused only a modest increase in formation of ·NO oxidation products. Production of NO2/- and NO3/- was inhibited by N(G)-monomethyl-L-arginine and cycloheximide. After exposure of these cells to a combination of the above cytokines, Escherichia coli LPS, and ZAS (cytomix Z), enhanced inducible nitric oxide synthase (iNOS) expression was indicated by an elevation in steady-state mRNA specific for iNOS (via Northern blot analysis) and increased immunofluorescence for iNOS after cell permeabilization, incubation with anti-iNOS antibody, and treatment with Cy3.18-conjugated rabbit-specific antibody. The extent of inflammatory mediator-induced ·NO production by alveolar epithelium, which exceeds that of other lung cell types, reveals new insight into mechanisms of pulmonary host defense and pathways of free radical-mediated lung injury.
KW - alveolar epithelium
KW - alveolar type II cell
KW - free radical
KW - lung
KW - nitric oxide
KW - nitric oxide synthase
KW - peroxynitrite
KW - superoxide
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U2 - 10.1152/ajplung.1995.268.3.l501
DO - 10.1152/ajplung.1995.268.3.l501
M3 - Article
C2 - 7534997
AN - SCOPUS:0028969941
VL - 268
SP - L501-L508
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
SN - 0363-6135
IS - 3 12-3
ER -