Persimmon leaf flavonoid has been shown to enhance brain ischemic tolerance in mice,but its mechanism of action remains unclear.The bilateral common carotid arteries were occluded using a micro clip to block blood flow for 10 minutes.After 10 minutes of ischemic preconditioning,200,100,and 50 mg/kg persimmon leaf flavonoid or 20 mg/kg ginaton was intragastrically administered per day for 5 days.At 1 hour after the final administration,ischemia/reperfusion models were established by blocking the middle cerebral artery for 2 hours.At 24 hours after model establishment,compared with cerebral ischemic rats without ischemic preconditioning or drug intervention,plasma endothelin,thrombomodulin and von Willebrand factor levels significantly decreased and intercellular adhesion molecule-1 expression markedly reduced in brain tissue from rats with ischemic preconditioning.Simultaneously,brain tissue injury reduced.Ischemic preconditioning combined with drug exposure noticeably improved the effects of the above-mentioned indices,and the effects of 200mg/kg persimmon leaf flavonoid were similar to 20 mg/kg ginaton treatment.These results indicate that ischemic preconditioning produces tolerance to recurrent severe cerebral ischemia.However,persimmon leaf flavonoid can elevate ischemic tolerance by reducing inflammatory reactions and vascular endothelial injury.High-dose persimmon leaf flavonoid showed an identical effect to ginaton. Persimmon leaf flavonoid has been shown to enhance brain ischemic tolerance in mice, but its mechanism of action remains unclear. The bilateral common carotid arteries were occluded using a micro clip to block blood flow for 10 minutes. After 10 minutes of ischemic preconditioning, 200, 100, and 50 mg / kg persimmon leaf flavonoid or 20 mg / kg ginaton intragastrically administered per day for 5 days. At 1 hour after the final administration, ischemia / reperfusion models were established by blocking the middle cerebral artery for 2 hours. At 24 hours after model establishment, compared with cerebral ischemic rats without ischemic preconditioning or drug intervention, plasma endothelin, thrombomodulin and von Willebrand factor levels significantly decreased and intercellular adhesion molecule-1 expression markedly reduced in brain tissue from rats with ischemic preconditioning. Simultaneously, brain tissue injury reduced.Ischemic preconditioning combined with drug exposure noticeably improved the effe cts of the above-mentioned indices, and the effects of 200 mg / kg persimmon leaf flavonoid were similar to 20 mg / kg ginaton treatment. this results in that ischemic preconditioning produces tolerance to recurrent severe cerebral ischemia. However, persimmon leaf flavonoid can elevate ischemicmic tolerance by reducing inflammatory reactions and vascular endothelial injury. High-dose persimmon leaf flavonoid showed an identical effect to ginaton.