Fig. 1.

Dose dependence of benzamil inhibition on transepithelial short-circuit currents (I_sc) level. A: representative I_sc in monolayers apically exposed to increasing concentrations of benzamil, a potent epithelial sodium channel (ENaC) inhibitor B: concentration-effect relationship. I_sc values were normalized to the basal level in the absence of benzamil. Experimental data were fitted with the Hill equation. The K_i values are 106 ± 6 nM (Hill coefficient 0.9) and 157 ± 14 nM (Hill coefficient 1.0) for wild-type (WT) and urokinase-like plasminogen activator (uPA) knockout (uPA^−/−) cells, respectively. N = 3–4 independent experiments. P = 0.65.