(B) Normalized time course of the steady-state E211G ClC-5 current amplitudes measured with (n=5) or without (n=4) internal ATP. Error bars show SEM. Red line represents a monoexponential fit to the data with a time constant of 108±8 s (SEM); currents measured with ATP-free pipette solution declined to 57.9±2.6% (SEM) of the initial amplitude. 