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...
ERG voltage-gated K+ channels regulate excitability and discharge dynamics of the medial vestibular nucleus neurones
Ist Teil von
The Journal of physiology, 2008-10, Vol.586 (20), p.4877-4890
Ort / Verlag
Oxford, UK: The Physiological Society
Erscheinungsjahr
2008
Link zum Volltext
Quelle
MEDLINE
Beschreibungen/Notizen
The discharge properties of the medial vestibular nucleus neurones (MVNn) critically depend on the activity of several ion
channel types. In this study we show, immunohistochemically, that the voltage-gated K + channels ERG1A, ERG1B, ERG2 and ERG3 are highly expressed within the vestibular nuclei of P10 and P60 mice. The role played
by these channels in the spike-generating mechanisms of the MVNn and in temporal information processing was investigated electrophysiologically
from mouse brain slices, in vitro , by analysing the spontaneous discharge and the response to square-, ramp- and sinusoid-like intracellular DC current injections
in extracellular and whole-cell patch-clamp studies. We show that more than half of the recorded MVNn were responsive to ERG
channel block (WAY-123,398, E4031), displaying an increase in spontaneous activity and discharge irregularity. The response
to step and ramp current injection was also modified by ERG block showing a reduction of first spike latency, enhancement
of discharge rate and reduction of the slow spike-frequency adaptation process. ERG channels influence the interspike slope
without affecting the spike shape. Moreover, in response to sinusoid-like current, ERG channel block caused frequency-dependent
gain enhancement and phase-lead shift. Taken together, the data demonstrate that ERG channels control the excitability of
MVNn, their discharge regularity and probably their resonance properties.