RESUMO
An important role for oxidative stress both as a consequence and as a cause of epileptic seizures has been suggested. Since Achillea wilhelmsii (A. wilhelmsii) has been considered to have the antioxidant effects as well as central nervous system depressant properties, the anti-seizure effects of the plant extract in addition to its effects on brain tissues oxidative damage were investigated in pentylenetetrazole (PTZ)-induced seizures model. Male Wistar rats were divided into 5 groups: (1) Control, (2) PTZ, (3-5) A. wilhelmsii extract groups (AWE). The animals in groups 2-5 were treated with saline or AWE (100, 200 or 400 mg/kg) before single injection of PTZ (90 mg/kg). Latency to first minimal clonic seizure (MCS) and the first generalized tonic-clonic seizures (GTCS) were recorded. The brain tissues were then removed for biochemical measurements. MCS latencies in extract treated groups were not different from PTZ group. The animals treated by 200 mg/kg of AWE had a significant higher GTCS latency in comparison with PTZ group (P<0.001). The MDA levels in PTZ group were significantly higher and the total thiol concentrations were lower than control animals. Pretreatment with all 3 doses of the extract resulted in a significant reduction in the MDA levels (P<0.05, P<0.01 and P<0.001) and a significant elevation in total thiol concentration, as compared with PTZ group (P<0.05 and P<0.01). The present study showed that the hydroalcoholic extract of A. wilhelmsii possesses an antioxidant effect in the brain in PTZ induced seizure model.