Zusammenfassung
Die Epilepsieforschung ist kein neues wissenschaftliches Feld - klinische und experimentelle
Untersuchungen werden seit Jahrzehnten betrieben. Trotz dieser fortwährenden Bemühungen
sind die Pathomechanismen der Epilepsie letztlich nicht vollständig geklärt - allerdings
gelangen in den letzten Jahren auch beachtliche Fortschritte. Vor allem durch die
Kombination genetischer, molekularer und funktioneller Analysen konnten wichtige Teilaspekte
der Entstehungsprozesse der Epilepsie aufgeklärt werden. Der vorliegende Übersichtsartikel
soll nach einer kurzen Erörterung der grundsätzlichen Faktoren der Erregbarkeit einzelner
Zellen und des neuronalen Zellverbandes in fünf kurzen Kapiteln einen Überblick über
den aktuellen Forschungsstand liefern. Innerhalb der ersten drei Abschnitte werden
Veränderungen spannungsabhängiger Ströme, der synaptischen Transmission und deren
Modulation sowie der Expression von Gap junctions beleuchtet. Darüber hinaus widmet
sich ein Abschnitt morphologischen Veränderungen. Der letzte Teil behandelt Aspekte
spezifischer genetischer Syndrome.
Abstract
Epilepsy research is not a recent scientific field - indeed clinical and experimental
investigations in epileptology have been carried out for decades. In spite of these
continued efforts, the pathomechanisms underlying epilepsy have so far remained elusive.
However, the recent years have brought significant advances, such that important aspects
of epileptic discharges and epileptogenesis have been unveiled. The present paper
aims to review the current state of the field. Beginning with an introductory section
on general principles of neuronal and network excitability, contributing factors such
as changes of voltage-gated currents, of synaptic transmission and of gap-junction
function will be highlighted. Furthermore, one section is devoted to morphological
changes, and the fifth to specific genetic syndromes.
Key words
epilepsy - neuronal excitability - bursting - Im
- Ih
- persistent sodium current - synaptic plasticity - NMDA - GABA - sprouting
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Prof. Dr. Rüdiger Köhling
Institut für Physiologie, Universität Rostock
Gertrudenstraße 9
18057 Rostock
Email: ruediger.koehling@uni-rostock.de
