Airways hyperresponsiveness and the effects of lung inflation.
Lung inflation has a beneficial effect on the airways of healthy subjects. It acts as a bronchoprotector, that is to prevent bronchoconstriction, and as a bronchodilator, in that it reverses bronchial obstruction. The bronchoprotective effect of deep inspiration is more potent than the bronchodilatory one, and the two phenomena appear to advocate different mechanisms. Asthmatics and rhinitics with airways hyperresponsiveness show an impairment in bronchoprotection induced by deep breaths, whereas the bronchodilatory effect, although reduced, is still effective. The lack of the bronchoprotective effect of deep inspiration may contribute to the development of airways hyperresponsiveness. The mechanisms through which lung inflation exerts its beneficial role in healthy subjects, and the factors impairing such an effect in those with airways hyperresponsiveness, are currently under investigation.
Scichilone
N
N
Division of Clinical Immunology, Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD 21224, USA.
Pyrgos
G
G
Kapsali
T
T
Anderlind
C
C
Brown
R
R
Permutt
S
S
Togias
A
A
D001249:Asthma / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D005541:Forced Expiratory Volume; D006801:Humans; D016210:Methacholine Chloride; D008954:Models, Biological; D009569:Nitric Oxide / Q000502:physiology; D012123:Pulmonary Ventilation
D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride; D009569:Nitric Oxide