Figure 4.

Kir 4.1 selectivity. Representative I–V plots with 110 mM K⁺, Rb⁺ or NH₄⁺ in the bath. (B) Summary of the data from the ion-substitution experiments. G_x/G_K was measured from the inward slope conductance 50 mV negative to the E_rev for each condition. P_x/P_K was calculated from the change in E_rev when the test ion completely replaced K⁺ in the bath using: P_X/P_K = exp((ΔErev·F)/(R·T)). Data represent means ± SEM for seven experiments.