FREE-RADICAL SCAVENGING ACTIVITY OF ZONISAMIDE AND ITS INHIBITORY EFFECT ON LIPID PEROXIDE FORMATION IN IRON-INDUCED EPILEPTOGENIC FOCI OF RATS

We evaluated the scavenging action of zonisamide, an antiepileptic agent, on hydroxyl radicals, superoxide radicals, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, and carbon centered radicals by the method of electron spin resonance (ESR) spectrometry. Zonisamide scavenged DPPH radicals and carbon centered radicals in a dose-dependent manner. However, hydroxyl radicals were scavenged at high concentrations (25 mM). Zonisamide inhibited the formation of ascorbic acid- and FeCl2- induced thiobarbituric acid reactive substances (TBARS) in rat cerebral cortical homogenates. This agent also reduced TBARS levels in the rat cortex having iron-induced epileptogenic foci, a model for post-traumatic epilepsy. Results suggest that zonisamide may be effective in treating post-traumatic epilepsy.