Comparison of the effect of three oral mucolytics on the ultrastructure of the tracheal epithelium in rabbits.

The effect of the application of a single oral dose of 100 mg of three mucolytic agents (N-acetylcysteine, carbocysteine and Na-2-mercaptoethane sulphonate) on the ultrastructure of the tracheal epithelium of healthy rabbits was studied. Due to the function of oral mucolytics the goblet cells were overstimulated and injured. Na-2-mercaptoethane sulphonate was the least irritating substance. Acetylcysteine produced the most pronounced injury of the goblet cells, followed by rapid differentiation of these cells. Oral administration of all mucolytics studied caused local impairment of mucus flow in the airways.