Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...

Details

Autor(en) / Beteiligte
Titel
Dependence of spontaneous neuronal firing and depolarisation block on astroglial membrane transport mechanisms
Ist Teil von
  • Journal of computational neuroscience, 2012-02, Vol.32 (1), p.147-165
Ort / Verlag
Boston: Springer US
Erscheinungsjahr
2012
Quelle
SpringerLink
Beschreibungen/Notizen
  • 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. We observed both the high [K  +  ] o -induced duration of spontaneous neuronal firing and the prevalence of depolarisation block to increase when reducing the magnitudes of the glial transport mechanisms. Further, in some parameter regions an oscillatory bursting spiking pattern due to the dynamical coupling of neurons and glia was observed. Bifurcation analyses of the neuron model and of a simplified version of the neuron-glia model revealed further insights about the underlying mechanism behind these phenomena. The above insights emphasise the importance of combining neuron models with detailed astroglial models when addressing phenomena suspected to be influenced by the astroglia-neuron interaction. To facilitate the use of our neuron-glia model, a CellML version of it is made publicly available.

Weiterführende Literatur

Empfehlungen zum selben Thema automatisch vorgeschlagen von bX