Protective Effect and Mechanism of Sanhuatang and Its Modifications on Cerebral Ischemia-reperfusion Injury in Rats / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo observe the protective effect of Sanhuatang and its modifications on the brain tissue of rats exposed to cerebral ischemia-reperfusion injury （CIRI） and explore its action mechanism and compatibility characteristics. MethodOne hundred and forty SD male rats of clean grade were randomly divided into the control group， sham-operation group， and operation group. The Longa suture method was employed to establish the CIRI model. The successfully modeled CIRI rats were further divided into five groups， namely the model group， nimodipine group， Sanhuatang without Notopterygii Rhizoma et Radix group， Notopterygii Rhizoma et Radix group， and Sanhuatang group， and treated with the corresponding medicines by gavage for five days. The cerebral infarct size in each group was examined by 2，3，5-triphenyltetrazolium chloride （TTC） staining， and the pathological changes in the brain tissue were observed by hematoxylin-eosin （HE） staining and electron microscopy. The mRNA and protein expression levels of Claudin-5， Occludin， and zonula occludens-1 （ZO-1） in brain tissues were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the control group， the model group exhibited markedly increased infarct size， obvious changes in brain morphology and ultrastructure， and down-regulated mRNA and protein expression of Claudin-5， Occludin， and ZO-1 （P<0.01）. Compared with the model group， both nimodipine and Sanhuatang significantly decreased the infarct size （P<0.01） and relived the pathological changes. The infarct sizes in the Sanhuatang without Notopterygii Rhizoma et Radix group and Notopterygii Rhizoma et Radix group were reduced without exhibiting a statistically significant difference. The mRNA and protein expression levels of Claudin-5， Occludin， and ZO-1 in the nimodipine group， Sanhuatang group， and Notopterygii Rhizoma et Radix group were up-regulated significantly in comparison with those in the model group （P<0.01， P<0.01）. The mRNA and protein expression levels of Claudin-5 and ZO-1 were higher in the Notopterygii Rhizoma et Radix group than in the Sanhuatang without Notopterygii Rhizoma et Radix group （P<0.01， P<0.01）. ConclusionSanhuatang exerts the protective effect against CIRI in rats possibly by regulating the expression of Claudin-5， Occludin， and ZO-1 and improving the blood-brain barrier function. Notopterygii Rhizoma et Radix in Sanhuatang may play an important role in the protection of rats from CIRI.