Cerebellar Purkinje Cell: resurgent Na current and high frequency firing (Khaliq et al 2003)

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Accession:48332
These mod files supplied by Dr Raman are for the below two references. ... we modeled action potential firing by simulating eight currents directly recorded from Purkinje cells in both wild-type and (mutant) med mice. Regular, high-frequency firing was slowed in med Purkinje neurons. In addition to disrupted sodium currents, med neurons had small but significant changes in potassium and leak currents. Simulations indicated that these modified non-sodium currents could not account for the reduced excitability of med cells but instead slightly facilitated spiking. The loss of NaV1.6-specific kinetics, however, slowed simulated spontaneous activity. Together, the data suggest that across a range of conditions, sodium currents with a resurgent component promote and accelerate firing. See papers for more and details.
Reference:
1 . Khaliq ZM, Gouwens NW, Raman IM (2003) The contribution of resurgent sodium current to high-frequency firing in Purkinje neurons: an experimental and modeling study. J Neurosci 23:4899-912 [PubMed]
2 . Raman IM, Bean BP (2001) Inactivation and recovery of sodium currents in cerebellar Purkinje neurons: evidence for two mechanisms. Biophys J 80:729-37 [PubMed]
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Model Information (Click on a link to find other models with that property)
Model Type: Neuron or other electrically excitable cell;
Brain Region(s)/Organism:
Cell Type(s): Cerebellum Purkinje GABA cell;
Channel(s): I Na,t; I K; I h; I K,Ca; I Sodium; I Calcium; I Potassium;
Gap Junctions:
Receptor(s):
Gene(s): Nav1.6 SCN8A;
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Activity Patterns; Ion Channel Kinetics; Action Potentials;
Implementer(s): Raman, Indira M [i-raman at northwestern.edu]; Bean, Bruce [bruce_bean at hms.harvard.edu]; Gouwens, Nathan W [nathan_gouwens at hms.harvard.edu];
Search NeuronDB for information about:  Cerebellum Purkinje GABA cell; I Na,t; I K; I h; I K,Ca; I Sodium; I Calcium; I Potassium; 
TITLE Purkinje Leak Current

: A passive purkinje cell leak current
NEURON {
	SUFFIX lkpkj
	NONSPECIFIC_CURRENT i
	RANGE i, e, g
}
PARAMETER {
	g = 5e-5	(siemens/cm2)  < 0, 1e9 >
	e = -60	(millivolt)
}
ASSIGNED {
	i  (milliamp/cm2)
	v  (millivolt)
}
BREAKPOINT { i = g*(v - e) }