Fig. 3.
Gating properties of nerve terminal channels differ from that of somatic and dendritic channels. A series of seven consecutive BK traces evoked by depolarizing: A, somatic; B, dendritic; or C, nerve terminal membrane patches from 0 to +40 mV. Channel activity was recorded in 10 μM free Ca2+ in an inside-out patch. C and O1, closed and open states, respectively. D to F, aggregate of 100 consecutive individual single channel traces recorded from one BK channel in a membrane patch excised from soma, dendrite, and terminal compartments, respectively. In all cases, BK current activation was best fit with a single exponential whose value (τ) is indicated below the aggregate traces.