"Motoneuron activity is strongly influenced by the activation of persistent inward currents (PICs) mediated by voltage-gated sodium and calcium channels. ... It has recently been suggested that a number of factors other than PIC can contribute to delta F (firing rate differences between motoneurons) values, including mechanisms underlying spike frequency adaptation and spike threshold accommodation. In the present study, we used a set of compartmental models representing a sample of 20 motoneurons with a range of thresholds to investigate how several different intrinsic motoneuron properties can potentially contribute to variations in F values. ... Our results indicate that, although other factors can contribute, variations in discharge hysteresis and delta F values primarily reflect the contribution of dendritic PICs to motoneuron activation.
Model Type: Neuron or other electrically excitable cell
Cell Type(s): Spinal cord lumbar motor neuron alpha ACh cell
Currents: I Na,p; I Na,t; I L high threshold; I K; I M; I K,Ca; I_AHP; I Calcium; I Sodium
Genes: Kv1.2 KCNA2; Kv1.9 Kv7.1 KCNQ1
Model Concept(s): Spike Frequency Adaptation
Simulation Environment: NEURON
Implementer(s): Powers, Randy [rkpowers at u.washington.edu]
References:
Powers RK, Heckman CJ. (2015). Contribution of intrinsic motoneuron properties to discharge hysteresis and its estimation based on paired motor unit recordings: a simulation study. Journal of neurophysiology. 114 [PubMed]