Fig. 2.

Chloroquine (CQ) inhibits the Kir6.2 current, interfering with channel-PIP₂ interaction. A to C, macroscopic currents recorded at −80 mV from excised inside-out patches of HEK-293 cells expressing Kir6.2 and the mutants (R134A and C166S) + SUR2A in presence of different chloroquine concentrations as indicated. D, concentration-response curve of the effect of chloroquine on Kir6.2(WT)/SUR2A channel currents measured at −80 mV, similar to those shown in A. The IC₅₀ of chloroquine was 11.8 ± 0.9 μM (n = 6 experiments at each concentration). E, summary of the inhibitory effects of chloroquine on the different channels (means ± S.E.M of n = 6 experiments at each concentration).