EFFECT OF S-CARBOXYMETHYLCYSTEINE LYSINE SALT ON MUCOCILIARY CLEARANCE IN RABBITS WITH SECRETORY-CELL METAPLASIA

A single intratracheal instillation of porcine pancreatic elastase (PP E, 100 U/Kg) induces in rabbits bronchial secretory cell metaplasia as well as emphysematous changes. The mucus hypersecretion and the marke d reduction of ciliated cells matched by a high percentage of atypical cilia are responsible for the delayed mucociliary clearance in this m odel. S-Carboxymethylcysteine lysine salt (SCMC-LYS, 0.35 g/Kg b.w.), given per os daily for 10 days starting 2 days before elastase adminis tration, significantly ameliorated the mucociliary clearance. The phar macological treatment did not modify the degree of secretory cell meta plasia and the percentage of atypical cilia, or prevent the alveolar w all destruction. At TEM examination, the morphological aspects of secr etion occurring in bronchial tree of PPE-treated animals were rarely v isible in the PPE + SCMC-LYS treated group. The beneficial, effect of SCMC-LYS on mucociliary clearance may be ascribed to an antisecretagog ue effect of this drug through elastase inhibition and to a reduction of mucus viscosity.