Abstracts

Rationale: Zonisamide has free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and carbon centered radicals, and inhibitory effect for the formation of lipid peroxide and 8-hydroxy-2'-deoxyguanosine in rat brain 30 min after iron solution injection into the left cortex of rat. In the present study effect of zonisamide on brain tissue damage after iron solution injection into the hippocampus using L-band electron spin resonance-computed tomography (ESR-CT). Methods: 3 Hours after injection of 10 ?l of 0.1 M FeCl3solution into the left hippocampus of rat, spin label carbamoyl-PROXYL was intraperitoneally injected and imaging of nitroxide radical in rat brain was obtained using L-band ESR-CT system. Zonisamide (100mg/kg) was injected 30 minutes before injection of iron solution. Malondialdehyde (MDA) was analyzed with the assay kit of LPO-586 (OXIS Int.). Results: Though carbamoyl-PROXYL does not cross the blood brain barrier,the uptake of nitroxide radicals was detected in the left hippocampus after injection of iron solution, and zonisamide inhibited the uptake of nitroxide radicals in the brain. MDA level was elevated in the left hippocampus after injection of iron soluiton, and zonisamide reduced the increase in MDA level.