Calu-3 is a well differentiated human bronchial cell line with the characteristics of the serous cells of airway submucosal glands. The submucosal glands play a major role in mucocillary clearance because they secrete electrolytes that facilitate airway hydration. Given the importance of both long and short term B adrenergic receptor agonists in the treatment of respiratory diseases, it is important to determine the role of the B receptor in normal physiological function. The current studies were designed to characterize the effect of epinephrine, the naturally occurring B adrenergic receptor agonist, on electrolyte transport. Interestingly epinephrine stimulated two anion secretory channels, the cystic fibrosis transmembrane conductance regulator and a Ca2+-activated Cl- channel, thereby potentially altering mucocillary clearance via multiple channels. Furthermore, the current results are consistent with, and extend, previous reports indicating that the two channels are functionally linked.