Comparison of current components among mouse BK_i and BK_s CCs and rat CCs. (A) The fraction of persistent BK current at the end of a 600-ms step to 80 mV after a several hundred–millisecond Ca²⁺ loading step to 10 mV is plotted for all mouse CCs (in slices) and then those defined as having largely BK_i current or largely BK_s current, along with the results from 21 rat CCs (in slices). (B) Mean (±SD) values for the maximal BK current density are displayed for each group of cells along with the individual values. No statistically significant differences were observed. (C) Mean (±SD) values of peak inward current observed after the initial step to 10 mV are displayed for each group of cells and also included 15 Slo1 KO CCs. (D) Mean (±SD) values of peak outward current during direct steps to 110 mV for each group of cells (including Slo1 KO). This current largely reflects Kv current, and rat CCs differ from mouse CCs with P < 0.001 (t test).