Fig. 9
Effects of SAF on single-channel NaV currents in GH3 cells. In (A), single-channel currents were induced through successive depolarizations (rate of 0.1 Hz) from a holding potential of −100 to −10 mV. Black graphs on the left indicate current traces during the control period (in the absence of SAF or SAF plus MGB); the red and blue graphs indicate the exposure to 10 μM SAF and 10 μM SAF plus 10 μM MGB, respectively. In the SAF plus MGB experiment, MGB was added 2 min after the addition of SAF. Channel opening in each record is shown as a downward deflection; the lowest traces on each side represent the average of 50 sweeps. Notably, SAF effectively increased the open-state probability of NaV channels, but the subsequent addition of MGB attenuated the SAF-induced increase in the likelihood of channel opening. However, the presence of neither SAF nor MGB in addition to SAF changed the single-channel amplitude of NaV channels in GH3 cells. (B) Graph showing effects of SAF, SAF plus MGB on the mean open time of NaV channel (mean ± standard error of the mean; n = 7). *Significantly different from control (P < 0.05) and **significantly different from SAF (10 μM) alone group (P < 0.05)