Effects of Aerosolized Amiloride on Mucociliary Transport Velocity and Transepithelial Potential Difference in Isolated Frog Palate

ABSTRACT An in vitro dose-response study was performed to determine the effects of aerosolized amiloride on transepithelial potential difference and mucociliary velocity. A preparation of isolated frog palate (Rana sculenta) was used for two groups: one submitted to amiloride nebulization (n = 7) and a control group submitted to vehicle (NaCl 0.45%) nebulization (n = 7). Transepithelial potential difference was measured by means of agar-filled microelectrodes connected to the high input of a grounded electrometer. Mucociliary velocity was determined by monitoring the movement of aluminum disks as tracer particles. Amiloride nebulization caused a significant dose-dependent increase in mucociliary velocity when compared to the control group (p < 0.05). The amiloride also turned the luminal surface more positive, promoting a decrease (in absolute value) in transepithelial potential difference when compared to the control group (p < 0.05). A positive and continuous (quadratic) association between mucociliary ...