Figure 4. Delayed outwardly rectifying K⁺ currents.

A, current responses to 200 ms voltage steps of 10 mV increments from a holding potential of −70 mV, in a whole-cell voltage-clamp recording applied at ∼1 Hz in the presence of 0.3 μm TTX before (left) and after (right) addition of 20 mm TEA⁺ to the bath. The inset shows the voltage pulse protocol. B, current–voltage relationship of the sustained TEA⁺-sensitive current calculated by substracting the mean steady state current in TEA⁺ from the mean steady state current before the addition of TEA⁺. The data were fitted with a Boltzmann equation (eqn (2): V_0.5 = 0.5 ± 1.1 mV, k = 11.2 ± 0.5 mV, n = 13).