RESUMEN
<p><b>OBJECTIVE</b>To explore the effects of paeoniflorin on blood brain barrier and pathological changes in brain ischemia.</p><p><b>METHOD</b>Mice were divided into sham operation group, model group, positive control group-Deng zhanhua tablet group and three different dose (high, middle, low-dose) groups of paeoniflorin. The neurological symptoms of rats were observed. The SOD of ischemic brain tissue, MDA BBB and EAA contents were determined. The ultrastructure on the brain cells was inspected by transmission electron microscope.</p><p><b>RESULT</b>Paeoniflorin had the protetive effects on 4VO model of total cerebral ischemia. Paeoniflorin could obviously increase SOD content, reduce MDA content in rat brain-tissue and alleviate oxidative stress damage by cerebral ischemia on rat brain. Paeoniflorin could improve pathological changes of cell nuclear, perikaryon, mitochondria and myelin sheath, which was the morphologic basis of the protective effect on ischemia. Paeoniflorin could alleviate the incrense of EAA content caused by and hypoxia and inhibit the excitatory neural toxicity by EAA.</p><p><b>CONCLUSION</b>Paeoniflorin has the protection effect on the brain edema after cerebral ischemia, the oxidative stress damage on brain tissue, the ultrastructure lesions of cells and the BBB. The protective mechanism may be related to inhibiting intracellular calcium overload, anti-free radical and reducing EAA content.</p>