SLC26A4 and cystic fibrosis: After 2 h of treatment, the resulting ASL pH was significantly different (P < 0.05) between CF-CTRL and CF-26A4KO epithelia for both alprostadil (ASL pH 7.0 ± 0.8 and 6.2 ± 0.2, n = 7, respectively, Fig. 5C) and indacaterol maleate (ASL pH 7.2 ± 0.6 and 6.4 ± 0.2, n = 7, respectively, Fig. 5C) suggesting that these two compounds were activating SLC26A4 to increase ASL pH.