"Exposed to a sufficiently high extracellular potassium concentration ([K?+?]o), the neuron can fire spontaneous discharges or even become inactivated due to membrane depolarisation (‘depolarisation block’). Since these phenomena likely are related to the maintenance and propagation of seizure discharges, it is of considerable importance to understand the conditions under which excess [K?+?]o causes them. To address the putative effect of glial buffering on neuronal activity under elevated [K?+?]o conditions, we combined a recently developed dynamical model of glial membrane ion and water transport with a Hodgkin–Huxley type neuron model. In this interconnected glia-neuron model we investigated the effects of natural heterogeneity or pathological changes in glial membrane transporter density by considering a large set of models with different, yet empirically plausible, sets of model parameters. ..."

Model Type: Glia; Extracellular; Neuron or other electrically excitable cell

Cell Type(s): Hodgkin-Huxley neuron; Astrocyte

Currents: I Potassium; I K; I Na,t

Model Concept(s): Epilepsy; Bursting; Action Potentials; Bifurcation; Activity Patterns

Simulation Environment: CellML (web link to model)

References:

Øyehaug L, Østby I, Lloyd CM, Omholt SW, Einevoll GT. (2012). Dependence of spontaneous neuronal firing and depolarisation block on astroglial membrane transport mechanisms. Journal of computational neuroscience. 32 [PubMed]