Computational modeling showed that the size of the Axon Initial Segment (AIS), but not its position within the somatodendritic domain, is the major causal determinant of the tonic firing rate in the intact model, by virtue of the higher intrinsic frequency of the isolated AIS. Further mechanistic analysis of the relationship between neuronal morphology and firing rate showed that dopaminergic neurons function as a coupled oscillator whose frequency of discharge results from a compromise between AIS and somatodendritic oscillators.
Model Type: Neuron or other electrically excitable cell
Cell Type(s): Substantia nigra pars compacta DA cell
Simulation Environment: NEURON
Implementer(s): Lopez-Jury, Luciana [lucianalopezjury at gmail.com]; Canavier, CC
Meza RC, López-Jury L, Canavier CC, Henny P. (2018). Role of the Axon Initial Segment in the Control of Spontaneous Frequency of Nigral Dopaminergic Neurons In Vivo. The Journal of neuroscience : the official journal of the Society for Neuroscience. 38 [PubMed]