Control of action potential afterdepolarizations in the inferior olive by inactivating A-type currents through K_V4 channels.

ABSTRACT: Neurons of the inferior olive (IO) fire action potentials with large, long-lasting afterdepolarizations (ADPs). Broader ADPs support more spikes in climbing fibre axons and evoke longer bursts of complex spikes in Purkinje cells, which affect the magnitude and sign of cerebellar synaptic plasticity. In the present study, we investigated the ionic mechanisms that regulate IO action potential waveforms by making whole-cell recordings in brainstem slices from C57BL6/J mice. IO spikes evoked from rest had ADPs of ∼30 ms. After 500-ms hyperpolarizations, however, evoked action potentials were brief (1-2 ms), lacking ADPs altogether. Because such preconditioning should maximally recruit depolarizing I_h and T-type currents and minimize repolarizing Ca-dependent currents known to shape

SUBMITTER: Sultan ZW 

PROVIDER: S-EPMC11922792 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature