Figure 10. Macroscopic current-voltage relationships for T339V CFTR.

A, T339V shows slight inward rectification with symmetrical Cl⁻-containing solutions. B, example current-voltage relationships used to investigate the anion selectivity of T339V, measured under biionic conditions with ClO₄⁻ or NO₃⁻ in the intracellular solution. Note that the permeability of these ions in T339V is similar to that observed in wild-type (Fig. 7). Patches were held at 0 mV and depolarizing voltage ramps were applied at a rate of 37.5–100 mV s⁻¹. Current-voltage relationships were leak subtracted as described in Methods.