Kv1 currents mediate a gradient of principal neuron excitability across the tonotopic axis in the rat lateral superior olive.

摘要: Principal neurons of the lateral superior olive (LSO) detect interaural intensity differences by integration excitatory projections from ipsilateral bushy cells and inhibitory inputs medial nucleus trapezoid body. The intrinsic membrane currents active around firing threshold will form an important component this binaural computation. Whole cell patch recording in vitro brain slice preparation was employed to study conductances regulating action potential (AP) principal neurons. Current-clamp recordings different showed two types pattern on depolarization, one group fired only a single initial AP had low input resistance while second multiple APs high resistance. Under voltage-clamp, single-spiking significantly higher levels dendrotoxin-sensitive, potassium current (ILT). Block ILT dendrotoxin-I allowed fire indicated that mediated Kv1 channels. Both neuronal were morphologically similar possessed amounts hyperpolarization-activated nonspecific cation conductance (Ih). However, predominated limb LSO (receiving frequency sound inputs) multiple-firing dominated limb. This functional gradient mirrored medio-lateral distribution Kv1.1 immunolabelling. We conclude channels underlie neuron properties. properties would render them particularly suited preserving timing information.