Figure 5.

Voltage-dependent K⁺ currents in gerbil OHCs. Current records for voltage steps (left), steady-state current-voltage relationships (middle) and conductance-voltage relationships (right) in: P16–P28 animals. CF and recording temperature in A–D (left panels) are shown next to traces. Currents were recorded by applying hyperpolarizing and depolarizing voltage steps in 10 mV nominal increments from the holding potential of −84 mV. Holding currents, plotted as zero current, were −148 pA (0.35 kHz), −175 pA (0.9 kHz), −441 pA (2.5 kHz) and −2484 pA (12 kHz).The current-voltage and conductance-voltage relations in (C) and (D) were corrected to 36 °C using Q₁₀ of 1.7. Conductance G_K determined from G_K = I/(V − E_K) where E_K is the current reversal potential, −75 mV. G_K-V relations fitted with single Boltzmann with G_K = G_{K, MAX}/(1 + exp (− (V−V_0.5)/V_S)) where G_{K, MAX}, V_0.5, V_S are: (A) 30 nS, −52 mV, 9.2 mV; (B) 60 nS, −63 mV, 8.4 mV; (C) 107 nS, −67 mV, 11 mV; (D) 280 nS, −56 mV, 18 mV.