Figure 8. MβCD treatment decreases intramembrane charge movement without significantly affecting voltage dependence.

A, charge movement recordings obtained in response to 25 ms pulses from a holding potential of −80 mV to the indicated potential in control and MβCD-treated fibres. B, average voltage dependence of charge moved in response to depolarization estimated by integration of the current recorded in 14 control and 17 MβCD-treated cells. Continuous lines correspond to a Boltzmann fit to the average populations. Parameters of the fit are Q_max= 1.32 and 0.86 pC, V_1/2,Q=−8.4 and −9.7 mV and k_Q= 13.5 and 15.0 mV for control and MβCD-treated cells, respectively. The dotted line corresponds to the normalization of the fit obtained in MβCD-treated cells with respect to the Q_max value determined under control conditions.