The reversal potential of currents was positively shifted when a long voltage ramp pulse followed the depolarizing steps. (top panel) The voltage protocol used for the experiment. (bottom panel) Representative traces of currents elicited by voltage ramp pulses are shown. (top panel). The red line represents the arithmetical difference between currents elicited by 500-ms (2) and 2-ms pulses (1). B. The summary bar graph represents the mean values of the reversal potentials of currents. (9 cells from 3 mice, paired Student t-test; data are presented as mean values ± s.e.m). 