Peripheral nerve axonal excitability in epileptic patients [Epilepsili hastalarda periferik sinir aksonal eksitabilitesi]

Introduction: sodium (na+) channels have an important role for action potential formation in both central nervous system (cns) and peripheral nervous system (pns). the persistent na+ current play a role in repetitive firing of action potentials caused by prolonged depolarization,thus could play a role in epilepsy. nerve excitability measurements are made to investigate biophysical properties and disturbances of impulse conduction in peripheral axons in human subjects. methods: in this study,it was aimed to study strength-duration properties of motor and sensory axons to evaluate whether there is a change in the current through persistent na+ channels of sensory and motor axons in peripheral nerves of epileptic patients because of the presence of similiar channels in pns. the study involved 17 patients newly diagnosed with partial epilepsy and 22 patients with primary generalized epilepsy who were not currently prescribed anticonvulsant therapy,and 15 control subjects. results: rheobase of motor fibres and stimulus strength at 0.1 ms and 1ms of motor fibres of total patients with epilepsy were higher than values of controls. conclusions: our results suggested a decreased axonal excitability and a possible decreased na+ conductances in peripheral nerves in patients with epilepsy. while there is hyperexcitability of central neurons,reduced peripheral nerve excitability may be in question in epilepsy.