EFFECT OF MACROLIDE ANTIBIOTICS ON CILIARY MOTILITY IN RABBIT AIRWAY EPITHELIUM IN-VITRO

We have studied ciliary beat frequency (CBF) of rabbit cultured trache al epithelium by a photoelectric method in-vitro. Addition of erythrom ycin and roxithromycin increased CBF in a dose-dependent fashion, wher eas clarithromycin was without effect. The rank order potency of macro lide was roxithromycin > erythromycin much greater than clarithromycin . The roxithromycin-induced increase in CBF was not altered by propran olol, AA-861, or verapamil, but partially attenuated by indomethacin. Roxithromycin increased intracellular cAMP concentrations. These resul ts suggest that certain macrolides can stimulate airway ciliary motili ty probably via prostaglandin- and cAMP-dependent regulatory pathways, which may affect mucociliary transport function in the respiratory tr act.