Fig. 5.

Isoproterenol-stimulated tracheal epithelial PKA activity 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. Tracheal epithelial cells were extracted and assayed for PKA activity 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 total tracheal epithelial cell PKA from six different rats (*p ≤ 0.05 for trachea treated with isoproterenol for 30 min compared with trachea treated with media only).