Neuronal adaptation involves rapid expansion of the action potential initiation site.
Nat Commun
; 5: 3817, 2014 May 23.
Article
em En
| MEDLINE
| ID: mdl-24851940
ABSTRACT
Action potential (AP) generation is the key to information-processing in the brain. Although APs are normally initiated in the axonal initial segment, developmental adaptation or prolonged network activity may alter the initiation site geometry thus affecting cell excitability. Here we find that hippocampal dentate granule cells adapt their spiking threshold to the kinetics of the ongoing dendrosomatic excitatory input by expanding the AP-initiation area away from the soma while also decelerating local axonal spikes. Dual-patch soma-axon recordings combined with axonal Na(+) and Ca(2+) imaging and biophysical modelling show that the underlying mechanism involves distance-dependent inactivation of axonal Na(+) channels due to somatic depolarization propagating into the axon. Thus, the ensuing changes in the AP-initiation zone and local AP propagation could provide activity-dependent control of cell excitability and spiking on a relatively rapid timescale.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Potenciais de Ação
/
Adaptação Fisiológica
/
Neurônios
Limite:
Animals
Idioma:
En
Revista:
Nat Commun
Assunto da revista:
BIOLOGIA
/
CIENCIA
Ano de publicação:
2014
Tipo de documento:
Article