NEUROPROTECTIVE drugs such asGinkgo bilobaextract (EGb 761) could prevent the ischemia-induced impairment of the Na, K-ATPase activity. In this study, Na, K-ATPase activity and expression, contents in fatty acids and malondialdehyde, an index of lipoperoxidation, were compared in the ipsilateral (ischemic) and the contralateral (unlesioned) cortices after 1 h of unilateral focal cortices cerebral ischemia in the mouse. EGb 761 (100 mg/kg) was administered daily to half of the animals for 10 days before ischemia. Ischemia significantly reduced Na, K-ATPase activity by about 40% and increased malondialdehyde content; EGb 761 pretreatment abolished these effects. The free radical scavenger properties of EGb 761 are a potential mechanism by which Na, K-ATPase injury and lipoperoxidation are prevented.