Lung inflammation and vascular remodeling after repeated allergen challenge detected noninvasively by MRI.
Am J Physiol Lung Cell Mol Physiol
; 292(3): L644-53, 2007 Mar.
Article
em En
| MEDLINE
| ID: mdl-17085517
ABSTRACT
Magnetic resonance imaging (MRI) has been used previously to follow noninvasively inflammatory processes in rat acute models of lung inflammation. Here the technique was applied to a model involving repeated intratracheal administration of ovalbumin (OA). Anatomical MRI was performed at different time points with respect to a single or multiple OA challenges in Brown Norway rats actively sensitized to the allergen. Vascular permeability was assessed using dynamic contrast-enhanced MRI (DCE-MRI). Bronchoalveolar lavage (BAL) fluid analysis and histology were performed to validate the MRI data. The time course of MRI signals after a single OA challenge reached a maximum at 48 h and decreased significantly at 96 h. After the second and subsequent challenges, the maximum signal occurred at 6 h with a time-dependent decline over the remainder of the time course. A reduction of the inflammatory response following repeated administration of OA was also detected by BAL fluid analysis. The decrease in vascular permeability assessed by DCE-MRI in repeatedly OA-challenged rats was consistent with the thickening of the vascular wall for vessels of diameter up to 300 microm revealed by histology. Angiogenesis of vessels smaller than 30 microm was also detected histologically. These results suggest that MRI can be used to detect the inflammatory response and vascular remodeling associated with chronic airway inflammation in rat models involving repeated administration of allergen. As the contrast agent used in the DCE-MRI experiments is approved for clinical use, there is potential to translate the approach to patients.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Asma
/
Brônquios
/
Alérgenos
/
Ovalbumina
/
Neovascularização Patológica
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
Am J Physiol Lung Cell Mol Physiol
Assunto da revista:
BIOLOGIA MOLECULAR
/
FISIOLOGIA
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
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