[Mucous membrane specific protease inhibitors in bronchial mucus in severe chronic obstructive bronchitis and in alpha 1-antitrypsin deficiency syndrome]

Abstract

In the bronchial mucus of 40 patients with chronic obstructive airway diseases we measured proteolytic activities, the total protein concentrations, alpha1-antitrypsin, alpha1-antichymotrypsin, and the free and bound proteinase inhibitors together with the total proteinase inhibition against trypsin and chymotrypsin. Without exception we always found free proteinase inhibitors together with proteolytic activities. The free-to-bound inhibitor rate was approximately 1:1 alpha1-Antitrypsin and alpha1-antichymotrypsin was measured in sputum only in very low concentrations. One patient with alpha1-anti-trypsin deficiency had no alpha1-antitrypsin, but high concentrations of total proteinase inhibitor-free and bound being in the same relation - in his bronchial mucus. In the alveolar part of the lung, the humoral proteinase inhibitors were effective. In the bronchial part of the lung the specific mucosal inhibitors had the decided importance. The proteinase inhibition of the mucosa-specific inhibitors is probably of great importance for the pathogenesis of airway obstruction, while the humoral proteinase inhibitors are responsible for the pathogenesis of emphysema.