Effects of hydrogen peroxide on the guinea-pig tracheobronchial mucosa in vivo
Författare
Summary, in English
Lumenal entry of plasma (mucosal exudation) is a key feature of airway inflammation. In airways challenged with histamine-type mediators and allergen the mucosal exudation response occurs without causing epithelial derangement and without increased airway absorption. In contrast, reactive oxygen metabolites may cause mucosal damage. In this study, involving guinea-pig airways, we have examined effects of H2O2 on airway exudation and absorption in vivo. Vehicle or H2O2 (0.1 and 0.5 M) was superfused onto the tracheobronchial mucosal surface through an oro-tracheal catheter. 125I-albumin, given intravenously, was determined in tracheobronchial tissue and in lavage fluids 10 min after challenge as an index of mucosal exudation of plasma. The tracheobronchial mucosa was also examined by scanning electron microscopy. In separate animals, 99mTc-DTPA was superfused 20 min after vehicle or H2O2 (0.1 and 0.5 M) had been given. A gamma camera determined the disappearance rate of 99mTc-DTPA from the airways as an index of airway absorption. The high dose of H2O2 (0.5 M) produced epithelial damage, increased the absorption of 99mTc-DTPA (P < 0.001), and increased the exudation of plasma (P < 0.001). Notably, it appeared that all extravasated plasma had entered the airway lumen within 10 min. These data demonstrate that H2O2 differs from exudative autacoids such as histamine by causing both epithelial damage and plasma exudation responses. These data also agree with the view that the epithelial lining determines the rate of absorption and is responsible for the valve-like function that allows lumenal entry of extravasated bulk plasma without any increased inward perviousness.
Avdelning/ar
Publiceringsår
1999
Språk
Engelska
Sidor
415-420
Publikation/Tidskrift/Serie
Acta Physiologica Scandinavica
Volym
165
Issue
4
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Medicinal Chemistry
- Radiology, Nuclear Medicine and Medical Imaging
- Immunology in the medical area
- Otorhinolaryngology
- Pharmacology and Toxicology
Nyckelord
- inflammation
- absorption
- airway
- plasma exudation
- ultrastructure
Status
Published
Forskningsgrupp
- Airway Inflammation and Immunology
- Clinical Physiology, Malmö
ISBN/ISSN/Övrigt
- ISSN: 0001-6772