Fig. 8. Functional expression of I_Ba during early stages of neuronal development. (A) The I_Ba current-voltage relationship (voltage steps lasting for 150 milliseconds, from -60 to +50 mV in 10 mV increments, HP -80 mV) in a representative bipolar LDS neuronal cell. The threshold of activation was between -60 and -50 mV and peak currents were measured at -10 mV. (B) The fraction of different I_Ba subtypes composing the whole cell current was evaluated using selective antagonists. (C,D) The percentage of the different current components did not significantly differ between bipolar- and multipolar neurons.