FIGURE 5.

Saturated cross-linking across the α subunit finger-thumb interface does not fully inhibit ENaC. MTS-2-MTS was added in three 15-s pulses (arrows) to wild type or αD171C,Y474C double mutants, with 30-s washes between pulses. DTT was then added followed by amiloride (amil). A, representative recording. B, the cumulative inhibition following each MTS-2-MTS pulse, normalized to the total amiloride-sensitive current immediately prior to the first MTS-2-MTS pulse. Values are mean ± S.D. (n = 5 (wild type) or n = 8 (double)).