Abstract
Since the tracheobronchial vasculature is the principal source of blood flow in the conducting airways, it can influence bronchial caliber [17], the bronchial response to thermal stress [4], the clearance of chemical mediators and other materials from the airway wall [18], the metabolism of circulating, biologically active substances before they reach the airway tissues [24], the distribution of systemically administered drugs to the airway, and the absorption of inhaled drugs from the airway. These functions may be relevant to the pathogenesis and treatment of bronchial asthma.