Calcium-activated SK channels influence voltage-gated ion channels to determine the precision of firing in globus pallidus neurons.

ABSTRACT: Globus pallidus (GP) neurons fire rhythmically in the absence of synaptic input, suggesting that they may encode their inputs as changes in the phase of their rhythmic firing. Action potential afterhyperpolarization (AHP) enhances precision of firing by ensuring that the ion channels recover from inactivation by the same amount on each cycle. Voltage-clamp experiments in slices showed that the longest component of the GP neuron's AHP is blocked by apamin, a selective antagonist of calcium-activated SK channels. Application of 100 nm apamin also disrupted the precision of firing in perforated-patch and cell-attached recordings. SK channel blockade caused a small depolarization in spike threshold and made it more variable, but there was no reduction in the maximal rate of rise during an acti

SUBMITTER: Deister CA 

PROVIDER: S-EPMC3329865 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature