Erdosteine enhances mucociliary clearance in rats with and without airway inflammation.

Erdosteine is a new homocysteine-derived expectorant and has been reported to have many mucolytic effects. In this report, we studied the activities of erdosteine on mucociliary clearance in normal and airway-inflammation-induced rats. In normal rats, erdosteine at doses of 100-600 mg/kg significantly promoted mucociliary clearance. However, erdosteine did not change the concentrations of mucopolysaccharides in bronchoalveolar lavage fluid (BALF). In the LPS-instillated rats, the mucociliary clearance was inhibited and the number of inflammatory cells, albumin concentration, and mucopolysaccharides concentration in BALF were increased. Erdosteine at doses of 100-600 mg/kg significantly attenuated the inhibition of mucociliary clearance and the increase of inflammatory cells, however, it did not prevent the increase of albumin and mucopolysaccharides. Other mucolytic drugs which are ambroxol and S-carboxymethylcysteine, had no effect. These results indicate that erdosteine promotes the mucociliary clearance in normal and airway-inflammation-induced rats.