Activity-dependent relocation of the axon initial segment fine-tunes neuronal excitability.

ABSTRACT: In neurons, the axon initial segment (AIS) is a specialized region near the start of the axon that is the site of action potential initiation. The precise location of the AIS varies across and within different neuronal types, and has been linked to cells' information-processing capabilities; however, the factors determining AIS position in individual neurons remain unknown. Here we show that changes in electrical activity can alter the location of the AIS. In dissociated hippocampal cultures, chronic depolarization with high extracellular potassium moves multiple components of the AIS, including voltage-gated sodium channels, up to 17 mum away from the soma of excitatory neurons. This movement reverses when neurons are returned to non-depolarized conditions, and depends on the activation o

SUBMITTER: Grubb MS 

PROVIDER: S-EPMC3196626 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature