Effects of various drugs on canine tracheal mucociliary transport.

A study of the effects of dehydration, atropine, terbutaline and N-acetylcysteine on canine tracheobronchial mucus is presented. Mucociliary clearance rates, mucus secretion volumes and mucus rheologic properties were studied. Clearance rates were studied by a radioisotope technique, mucus collected by a canine "tracheal pouch" method and rheologic studies performed on a microrheometer. Clearance rate was unaffected by dehydration and terbutaline, increased by N-acetylcysteine and decreased by atropine. Secretion volume was increased by terbutaline while dehydration and atropine were without effect. Rheologic factors were increased by dehydration and atropine while terbutaline was without an effect. The effects of N-acetylcysteine on secretion volume and rheologic properties could not be studied because of the nature of the techniques employed.