"Globus pallidus (GP) neurons recorded in brain slices show significant variability in intrinsic electrophysiological properties. To investigate how this variability arises, we manipulated the biophysical properties of GP neurons using computer simulations. ... Our results indicated that most of the experimental variability could be matched by varying conductance densities, which we confirmed with additional partial block experiments. Further analysis resulted in two key observations: (1) each voltage-gated conductance had effects on multiple measures such as action potential waveform and spontaneous or stimulated spike rates; and (2) the effect of each conductance was highly dependent on the background context of other conductances present. In some cases, such interactions could reverse the effect of the density of one conductance on important excitability measures. ..."
Model Type: Neuron or other electrically excitable cell
Cell Type(s): Globus pallidus neuron
Currents: I Na,p; I Na,t; I L high threshold; I A; I K,leak; I K,Ca; KCNQ1
Transmitters: Ions
Model Concept(s): Dendritic Action Potentials; Parameter Fitting; Active Dendrites; Detailed Neuronal Models; Methods; Parkinson's
Simulation Environment: GENESIS
Implementer(s): Gunay, Cengiz [cgunay at emory.edu]; Edgerton, Jeremy R. [jedgert at emory.edu]; Hanson, Jesse E.
References:
Günay C, Edgerton JR, Jaeger D. (2008). Channel density distributions explain spiking variability in the globus pallidus: a combined physiology and computer simulation database approach. The Journal of neuroscience : the official journal of the Society for Neuroscience. 28 [PubMed]