We studied the effects of azelastine and salbutamol on the sulfur dioxide (SO2) -induced inhibition of airway ciliary motility. Azelastine and salbutamol dose-dependently increased ciliary beat frequency (CBF) of rabbit tracheal epithelium, as detrmined by a photoelectric technique. Perfusate bubbled with 10 ppm SO2 greatly decreased CBF and intracellular cyclic AMP levels, an effect that was reversed by pretreatment of cells with azelastine and salbntamol.
Thus, azelastine might protect against SO2-induced airway injury by accumulating cyclic AMP in epithelial cells.
