The h-channel: a potential channelopathy in epilepsy?

Ion channelopathy is a proven cause of inherited human epilepsy, and may play a role in acquired epileptic syndromes as well. Of the many ion channel causes of epilepsy, the h-channel is a potential new addition. H-channels are voltage-gated ion channels with unique biophysical properties. The h-channel exerts a significant modulatory influence on neuronal excitability, and is a target of antiepileptic drugs. Further, its activity is influenced by seizures, raising the question of whether it may play a role in epileptogenesis as well. This review summarizes the evidence for the contribution of h-channels to seizures and epilepsy, and outlines hypotheses concerning the existence of an "h-channelopathy" in human epilepsy.