Table 3.

Voltage-gated ion channels that undergo plasticity during acquired epilepsies

Channel/current	Form of epilepsy	Nature of change	Impact on cell excitability	Reference
HCN channel/ HCN current Ih	Temporal lobe epilepsy (TLE)	Sustained reduction in current density following status epilepticus (SE) induction	Enhanced pyramidal and interneuron excitability	Dugladze et al. 2007; Jung et al. 2007; Marcelin et al. 2009; Shah et al. 2004; Shah et al. 2012; Shin et al. 2008; Wierschke et al. 2010
HCN channels/ HCN current Ih	Febrile seizure-induced epilepsy	Enhanced HCN channel expression and current	Enhanced rebound activity following inhibitory post-synaptic potentials (IPSPs)	Bender et al. 2003; Chen et al. 2001; Dyhrfjeld-Johnsen et al. 2008
HCN current Ih	Fragile X syndrome	Enhanced HCN channel current	Impaired long-term potentiation (LTP in pyramidal neurons)	Brager et al. 2012
CaV3.2 channels/ T-type Ca2+ current	TLE	Transient elevation of expression and current from SE to chronic epilepsy	Enhanced pyramidal cell bursting	Becker et al. 2008; Su et al. 2002
KV4.2 channels/ A-type K+ current	TLE	Reduction 1 week after SE and persisting during chronic TLE	Enhanced pyramidal cell dendritic excitability	Bernard et al. 2004; Monaghan et al. 2008
BK channels	TLE	Reduction in expression during chronic TLE	??	Pacheco Otalora et al. 2008
Kir2 channels/ inward rectifier current	Chronic TLE	Enhanced expression	Reduced dentate gyrus granule cell excitability	Young et al. 2009
KCNN1 (SK1) KCNN2 (SK2) and KCNN3 (SK3) channels	TLE	Transient reduction during chronic TLE	Increased number of hippocampal population spikes	Oliveira et al. 2010
Persistent sodium current	TLE	Sustained increase following SE	Enhanced neuronal excitability	Agrawal et al. 2003; Chen et al. 2011; Epsztein et al. 2010; Hargus et al. 2011; Vreugdenhil et al. 2004

Full references can be found in Supplementary information. The neuronal localization of some of the channel proteins is shown in Figure 1.