Figure 1.

The membrane capacitance (A) of an outer hair cell (Inset) just before the trypsin-containing pipette medium is injected. The voltage dependence is obtained by using a waveform that consists of an ascending staircase followed by a descending one (B). The short waveform has 3-ms steps and the total duration of 105 ms (lower time scale). The long waveform has 100-ms steps and the total duration of 3.5 s (upper time scale). The membrane capacitance is obtained from capacitive charge transfer elicited at each voltage step. Using either the long or the short waveform does result in a clear difference in the capacitance. The solid line in A represents the best fit with Eq. 1. The solid line represents a best fit, which gives q* = (0.75 ± 0.06) e, C_pk = (19.1 ± 1.2) pF (or N = (2.2 ± 0.3) × 10⁷), V₀ = (−46.0 ± 0.8) mV, and C_lin = (18.2 ± 1.5) pF.