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A balance equation determines a switch in neuronal excitability.

ABSTRACT: We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a balance between ion channels that provide a negative feedback at resting potential (restorative channels) and those that provide a positive feedback at resting potential (regenerative channels). Geometrically, the condition imposes a transcritical bifurcation that rules the switch of excitability through the variation of a single physiological parameter. Our analysis of six different published conductance based models always finds the transcritical bifurcation and the associated switch in excitability, which suggests that the mathematical predictions have a physiological relevance and that a same regulatory mechanism is potentially involved in the excitability and signaling of many neurons.

SUBMITTER: Franci A

PROVIDER: S-EPMC3662658 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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A balance equation determines a switch in neuronal excitability.

Franci Alessio A Drion Guillaume G Seutin Vincent V Sepulchre Rodolphe R

PLoS computational biology 20130523 5

We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a balance between ion channels that provide a negative feedback at resting potential (restorative channels) and those that provide a positive feedback at resting potential (regenerative channels). Geometrically, the condition imposes a transcritical bifurcation that rules the switch of excitability ...[more]

PMID: 23717194

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