Abstracts

Riluzole may be one of candidates as supplementary medications for treatment of epilepsy. However, there is little information about the anti-epileptic effect of riluzole, since evaluation of this drug has been mostly performed in normal animals. Therefore, the comparison of effects of riluzole with valproic acid (VPA) was conducted in the pilocarpine-induced temporal lobe epilepsy model (a complex partial seizure model) and the [gamma]-hydroxybutyrate lactone (GBL)-induced absence seizure models., Following VPA or riluzole treatment, electrophysiological and immunohistochemical studies were performed in pilocarpine- or GBL-induced epilepsy models., Both VPA and riluzole treatment saliently reduced vesicular glutamate transporter (VGLUT) immunoreactivities and fEPSP slope. Riluzole treatment completely inhibited pre-ictal spikes and spike-wave discharges (SWD) in pilocarpine- and GBL-induced epilepsy model, although VPA treatment partially inhibited. Both VPA and riluzole reduced paired-pulse inhibition in the pilocarpine-induced epilepsy model. In the GBL-absence seizure model, riluzole enhanced paired-pulse inhibition, but VPA reduced it., These results suggest that inhibition of presynaptic glutamate release by riluzole may be more effective to reduce seizure activity both in complex partial seizure and in absence seizure than VPA.,