ABSTRACT
Changes in bronchial microvasculature are present in chronic inflammatory
airway disease and may contribute to airway remodeling in asthma. In addition to
hypertrophy and hyperplasia of airway smooth muscle (1), increase in mucous
glands (2), and thickening of the reticular basement membrane (3), some
significant qualitative and quantitative changes in airway blood vessels may
occur in asthma. Early studies on the pathology of asthma showed edematous
bronchial mucosa with dilated and congested blood vessels in patients with fatal
disease (4,5). More recent in vivo quantitative studies in asthmatic patients found
an increase in the total number of vessels and in vascular area when compared to
control subjects (6,7). Currently, it is assumed that the bronchial microcirculation
in asthma may be involved via at least three different mechanisms: angiogenesis,
dilatation, and permeability (8).