Figure 3. Activation of K_ATP channels by diazoxide delayed the current inactivation and prolonged the iron-transport function of DMT1.

(A) DMT1-mediated Fe²⁺ current was evoked from voltage ramps. Whole-cell currents were elicited by repeated voltage ramps (−120 mV to +100 mV, duration 500 ms) from a holding potential of 0 mV. The time interval between ramps was 10 s. (B) Proton-dependent Fe²⁺ currents were measured in the absence and presence of 100 μM diazoxide. The solution exchange protocol is indicated above the current readings. **P < 0.01, between currents in the presence and absence of diazoxide with 100 μM Fe²⁺ at a pH 4.2, n = 8.