[Electron microscopic study of guinea pig tracheal epithelium after administration of NAB 365 (author's transl)].

After application of 4-amino-alpha-[(tert.-butylamino)methyl]-3,5-dichlorobenzyl alcohol hydrochloride (clenbuterol, NAB 365) the following changes in the secretory cells of the tracheal epithelium of the guinea pig can be visualised by electron microscope: 1. increase of membrane-bordered structures which might be regarded as primary lysosomes, 2. a faster and more pronounced loosening of secretion granula. These findings suggest a selective site of action of the substance at the lysosomal system. It is stimulated, loosens the secretion intensively already within the cell, and possibly develops some activity even in the lumen. These conceptions can serve as an explanation of the clinically and experimentally demonstrated secretolytic effect.