Fig. 8.

Lack of an effect by EtOH on native DSM single BK channel unitary conductance under the condition of highly elevated intracellular [Ca²⁺]. A: representative recordings from a single experiment (inside-out configuration at +40 mV) with K⁺ solution containing ∼10 μM free [Ca²⁺] for the intracellular (bath) compartment before (left) and after (right) the application of 0.3% EtOH at −20, +20, and +30 mV. C and the dotted line depict the closed channel state, arrowheads the open channel states, and the dashed parallel dashed lines breaks in the y-axis as no single channel events were recorded within the limits. B: unitary current-voltage relationship for the same patch depicted in A, and also in Fig. 7A, in the presence or absence of 0.3% EtOH. Represented slope single conductance values were 227 pS for pre-EtOH control and 223 pS for 0.3% EtOH. C: summary of the unitary conductance values in the presence or absence of 0.3% EtOH in 8 inside-out excised patch experiments in the presence of ∼10 μM intracellular free [Ca²⁺] (N = 4); ns, nonsignificant effect (P > 0.05) vs. pre-EtOH control values.