Flow-dependent activation of ENaC. (A) Typical macroscopic currents elicited by voltage steps from 60 to -100 mV in voltage clamped CHO cells before and after flow stimulation (low level - middle recording, and high level - right). (B) Current traces were recorded before and after flow stimulation when cells were treated with amiloride (10 μM). (C) The current through ENaC elicited by voltage ramps (60 to -100 mV from a holding potential of 40 mV) applied every 3 s with and without perfusion. Amiloride 10 μM applied at the end of the experiment. (D) Representative current-voltage relation of macroscopic, amiloride-sensitive ENaC currents in CHO cells before (control) and after flow stimulation (perfusion). (E) Summary graph of amiloride-sensitive current density at -80 mV for CHO cells expressing mENaC in control conditions and after flow stimulation. Values are means ± SE of 18 experiments.