Effect of ultrasonic nebulization of miraclid® on the proteolytic activity in tracheobronchial secretions of rats

Experimental studies of acute inflammation of the tracheobronchial lumen of rats suggest that protease inhibitor increases in tracheobronchial secretions in order to control inflammation. Recent studies have shown that the polyvalent protease inhibitor, Miraclid®, derived from human urine, is useful for treating DIC and acute pancreatitis. In view of this information, local administration of Miraclid was expected to diminish acute inflammation of the respiratory tract by creating a favorable balance in the protease-antiprotease system. Before the chemotherapeutic use of locally administered Miraclid, the inhibitory activity of Miraclid on various proteases was first estimated in vitro. Administration of Miraclid by means of ultrasonic nebulization was then investigated in rats. The results can be, summarized as follows. 1. During ultrasonic nebulization, the inhibitory activity of Miraclid on protease was decreased by means of mechanical stimulation in comparison to the activity before nebulization. 2. Compared to administration of physiological saline into the tracheobronchial lumen, administration of Miraclid by means of ultrasonic nebulization decreased the fibrinolytic activity in tracheobronchial secretions.