Expression of Inducible Nitric Oxide in Human Lung Epithelial Cells

doi:10.1006/bbrc.1994.2169

Biochemical and Biophysical Research Communications

Volume 203, Issue 1, 30 August 1994, Pages 209-218

https://doi.org/10.1006/bbrc.1994.2169 Get rights and content

Abstract

Nitric oxide (NO) is increased in the exhaled air of subjects with several airway disorders. To determine if cytokines could stimulate epithelial cells accounting for the increased NO, the capacity of the proinflammatory cytokines (cytomix: tumor necrosis factor-α, interleukin-1β, and interferon-γ) to increase inducible nitric oxide synthase (iNOS) was investigated in A549 and primary cultures of human bronchial epithelial cells. Cytomix induced a time-dependent increase in nitrite levels in culture supernatant fluids (p<0.05). Increased numbers of cells stained for iNOS and increased iNOS mRNA was detected in the cytokine-stimulated cells compared to control (p<0.05). Dexamethasone diminished the cytokine-induced increase in nitrite, iNOS by immunocytochemistry, and iNOS mRNA. These data demonstrate that cytokines, such as those released by mononuclear cells, can induce lung epithelial iNOS expression and NO release, and that this is attenuated by dexamethasone.

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Regular ArticleExpression of Inducible Nitric Oxide in Human Lung Epithelial Cells

Abstract

Regular Article
Expression of Inducible Nitric Oxide in Human Lung Epithelial Cells