Action potential initiation in neocortical inhibitory interneurons.
Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumi...
Guardado en:
Autores principales: | , , , , , , , , |
---|---|
Formato: | article |
Lenguaje: | EN |
Publicado: |
Public Library of Science (PLoS)
2014
|
Materias: | |
Acceso en línea: | https://doaj.org/article/9e15afc91a904a89990ef230a7cb696b |
Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
Sumario: | Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na+ channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (∼7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, NaV1.2 was found accumulated at AIS of SST but not PV cells; reducing NaV1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na+ channels in interneurons and their contribution to AP generation and regulation of network activity. |
---|