THE ROLE OF AIRWAY MUCUS IN PULMONARY TOXICOLOGY

Airway mucus is a complex airway secretion whose primary function as p art of the mucociliary transport mechanism is to to serve as renewable and transportable barrier against inhaled particulates and toxic agen ts. The theologic properties necessary for this function are imparted by glycoproteins, or mucins. Some respiratory disease states, e.g., as thma, cystic fibrosis, and bronchitis, are characterized by quantitati ve and qualitative changes in mucus biosynthesis that contribute to pu lmonary pathology. Similar alterations in various aspects of mucin bio chemistry and biophysics, leading to mucus hypersecretion and altered mucus theology, result from inhalation of certain air pollutants, such as ozone, sulfur dioxide, nitrogen dioxide, and cigarette smoke. The consequences of these pollutant-induced alterations in mucus biology a re discussed in the context of pulmonary pathophysiology and toxicolog y.