Fig. 3.

Tracheal epithelial CBF in cigarette smoke-exposed and ethanol-fed rats. Rats fed various concentrations of ethanol in their diets for 5 weeks were either sham exposed (white and gray bars) or cigarette smoke exposed (hatched and black bars) for a total of 12 weeks. Excised tracheal rings were assayed for ciliary beat frequency (CBF) in the absence (white and hatched bars) and presence (gray and black bars) of 100 μM isoproterenol (ISO) for 30 min. Bars represent SEM of six different rats. Data from each rat represent the average of 10 or more tracheal rings (*p ≤ 0.05 for tracheal rings treated with isoproterenol for 30 min compared with those treated with media only).