Deactivating of the K ⁺ -current from Xenopus oocytes expressing K _V 7.2 channels WT and R198H at pHEXT 6.0 and 8.0. (A) Example of K⁺-currents activated with a +40-mV pulse of exponentially increasing duration followed by deactivation at −105 mV. Deactivating phase inside dashed square. (B) Detailed deactivating K⁺-currents in oocytes expressing WT (left) and the mutant R198H (right) at pH_EXT 6.0 (top) and 8.0 (bottom). Notice that the difference in the time scale for deactivation of the mutant R198H is at pH_EXT 8.0.