Fig. 5.

Activation of hERG channels by PD-118057 and inhibition of hERG channels by ciclopirox in APPC assays. The capture screen from DataXpress of a representative whole-cell patch clamp recording showed activation of hERG channels by PD-118057 (A) and inhibition by ciclopirox (C). Red vertical line indicated addition of buffer control and green vertical triple lines indicated triple additions of drugs. Drug concentrations (μM) were listed at the top of the green lines. Red cross indicated the time point when hERG tail current was measured by the system. Upon washout (blue vertical line), hERG tail current reduced from activation by PD-118057 or recovered from inhibition by ciclopirox, indicating that activation PD-118057 or inhibition by ciclopirox was not due to current run-up or run-down, respectively. (B) The corrected tail currents (nA) in the presence of PD-1158057 were extracted from DataXpress program, and normalized to basal currents (with buffer = 100%), and plotted again PD-118057 concentrations (n = 3). (D) The tail currents in the presence of ciclopirox were extracted from DataXpress, normalized to percentage inhibition, and plotted for against ciclopirox concentrations (n = 4).