Mucosal nitric oxide may tonically suppress airways plasma exudation
Författare
Summary, in English
In a search for airway epithelial mechanisms that may affect the subepithelial microcirculation, we examined plasma exudation responses to NG-nitro-L-arginine-methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor. L-NAME was applied topically on the tracheal mucosa of guinea pigs that had previously received 125I-albumin and/or colloidal gold particles (5 nm) intravenously. Luminal entry of plasma was determined by the levels of 125I-albumin in tracheal lavage fluid. Topical L-NAME (2.2, 9, and 22 mumol), but not intravenous L-NAME (375 mumol/kg), produced plasma exudation into the airway lumen (p < 0.01 to p < 0.001). The L-NAME enantiomer NG-nitro-D-arginine-methyl ester (D-NAME, 9 mumol) produced no exudative response. Coadministration of L-arginine (27 mumol) abolished the L-NAME-induced exudation. The extravasated plasma was distributed in the lamina propria and between epithelial cells (colloidal gold). The epithelial surface structure (scanning electron microscopy) appeared intact. Staining with nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase suggested that epithelial basal may contain nitric oxide synthases. We suggest that endogenously released nitric oxide from epithelial or other superficial cells tonically suppresses the macromolecular permeability of the subepithelial microcirculation.
Publiceringsår
1994
Språk
Engelska
Sidor
227-232
Publikation/Tidskrift/Serie
American Journal of Respiratory and Critical Care Medicine
Volym
150
Issue
1
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
American Thoracic Society
Ämne
- Respiratory Medicine and Allergy
Status
Published
Forskningsgrupp
- Airway Inflammation and Immunology
ISBN/ISSN/Övrigt
- ISSN: 1535-4970