Long-term administration of Polygonum multiflorum Thunb. reduces cerebral ischemia-induced infarct volume in gerbils.

Focal cerebral ischemia was produced by an occlusion of the middle cerebral artery for 1, 3 and 24 hours in gerbils. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride (TTC) transcardiac perfusion 24 hours after cerebral ischemia. Significant and consistent infarct sizes were produced in gerbils subjected to 24-hour occlusion of the middle cerebral arterey when compared to the 1 and 3-hour occlusion group. Longterm pretreatment of the 50% ethanol extract of Polygonum multiflorum Thunb. for 2 weeks significantly reduced the infarct volume by 50% as compared to that of the 24-hour occlusion group. The results revealed that long term pretreatment of Polygonum multiflorum Thunb. may protect the brain against focal cerebral ischemia.