Protecting mechanism of puerarin on the brain neurocyte of rat in acute local ischemia brain injury and local cerebral ischemia-reperfusion injury.

The present study was designed to investigate the possible properties of the injured brain neurocytes, the expression of heat shock protein70 (HSP70) and Fas protein after acute local ischemia brain injury and local cerebral ischemia-reperfusion injury in rats and to investigate the protecting mechanism of puerarin on the brain neurocytes of rats in acute local ischemia brain injury and local cerebral ischemia-reperfusion injury. A rat model of acute local cerebral ischemia was made by ligatting the middle cerebral artery. The rat model of local cerebral ischemia and reperfusion injury was made by ligatting the middle cerebral artery for 30 min then opened for 30 min. Rats of puerarin treating group were injected with puerarin in dose of 30 mg/kg(-1) by intraperitoneal injection 30 min before ischemia. HSP70 and Fas protein expressions in brain tissue were detected by SP method of histochemistry. In addition, dead brain neurocytes were counted and their morphology was observed. The results indicated that puerarin can limit the tissue injury caused by local cerebral ischemia injury through improving expression of HSP70, and limit the tissue injury caused by local cerebral ischemia-reperfusion through decreasing the Fas expression and improving expression of HSP70. On the basis of these results, it may be concluded that puerarin can protect the brain neurocytes of rats in acute local ischemia brain injury and local cerebral ischemia-reperfusion injury, which may be different according to the different injury mechanism.