Resumen
We developed a simple capillary electrophoresis (CE) method to measure nitrite and nitrate concentrations in sub-microliter samples of rat airway surface liquid (ASL), a thin (10-30 μm) layer of liquid covering the epithelial cells lining the airways of the lung. The composition of ASL has been poorly defined, in large part because of the small sample volume (∼1-3 μl per cm2 of epithelium) and difficulty of harvesting ASL. We have used capillary tubes for ASL sample collection, with microanalysis by CE using a 50 mM phosphate buffer (pH 3), with 0.5 mM spermine as a dynamic flow modifier, and direct UV detection at 214 nm. The limit of detections (LODs), under conditions used, for ASL analysis were 10 μM for nitrate and 30 μM for nitrite (S/N=3). Nitrate and nitrite were also measured in rat plasma. The concentration of nitrate was 102±12 μM in rat ASL and 70±1.0 μM in rat plasma, whereas nitrite was 83±28 μM in rat ASL and below the LOD in rat plasma. After instilling lipopolysaccharide intratracheally to induce increased NO production, the nitrate concentration in ASL increased to 387±16 μM, and to 377±88 μM in plasma. The concentration of nitrite increased to 103±7.0 μM for ASL and 138±17 μM for plasma.
Idioma original | English |
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Páginas (desde-hasta) | 147-154 |
Número de páginas | 8 |
Publicación | Journal of Chromatography B: Biomedical Sciences and Applications |
Volumen | 762 |
N.º | 2 |
DOI | |
Estado | Published - oct. 25 2001 |
Publicado de forma externa | Sí |
Nota bibliográfica
Funding Information:This research was supported by the Canadian Cystic Fibrosis Foundation, the Montreal Chest Institute Research Centre and the J.T. Costello Memorial Fund. E.A.C. was the recipient of a fellowship from the Canadian Cystic Fibrosis Foundation. D.H.E. is a recipient of a scholarship from the Fonds de Recherché en Santé du Québec.
ASJC Scopus Subject Areas
- General Chemistry
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't