[Mechanism and management of airway hypersecretion in obstructive lung disease]

Airway hypersecretion is a characteristic feature of chronic bronchitis and influences progression and prognosis of the disease, but the underlying mechanism remains uncertain. The increase in intraluminal viscid mucus may lead to disturbance of airway mucociliary clearance and deterioration of obstructive impairment of pulmonary function. Airway surface fluid is composed of mucous glucoprotein released from submucosal glands and goblet cells and water from airway epithelial cells, and the secretory function can be regulated by autonomic nervous system and a variety of chemical mediators and cytokines. Although several drugs may alter secretory responses and physicochemical properties of the sputum, it seems important to select mucoregulating drugs after understanding the mechanisms of hypersecretion and impaired mucociliary transport under individual conditions.