Table 1 The function of ion channel and receptor in normal and epileptic tissue [7]
From: Biomolecular mechanisms of epileptic seizures and epilepsy: a review
Ion channels or receptor | Normal brain | Epileptic brain |
|---|---|---|
Voltage-gated Na+ channles | Subthreshold EPSP, upstroke of the action potential | Repetitive action potential firing |
Voltage-gated K+ channles | Action potential downstroke | Action potential repolarization |
Voltage-gated Ca+ channles | Released transmitter, transports a depolarizing charge from the dendrite to the soma | A pathogenic intracellular process is activated by excessive transmitter release |
Ca2+-dependent K+ channels | After hyperpolarization following action potential, sets refractory period | Limit repetitive firing |
Non-NMDA receptor | Fast EPSP | Initiates paroxysmal depolarization shift |
NMDA receptor | Prolong, slow EPSP | Maintain paroxysmal depolarization shift, Ca2+ activates pathologic process |
GABA receptor | IPSP | Limit excitation |
Na+ - K+ pump | Restore ionic equilibrium | Prevent K+ - induced depolarization |