Neuroprotective Mechanism Of Dl-3n-Butylphthalide On Focal Cerebral Ischemia Reperfusion Injury In Rats

Objective:To investigate neuroprotective of dl-3n-butylphthalide on focal cerebral ischemia reperfusion injury in rats and study the mechanisms of it by analyzing the correlation between Caspase-3and PDCD-5.Methord:Two hundred and eight healthy male Wistar rats were chosen to establish cerebral ischemia reperfusion model with middle cerebral artery thread embolism methord and were randomly divided into the sham operation group(Sixteen), model group(Ninety-six) and the Butylphthalide treatment group(Ninety-six). The later two groups were divided into six subgroups according to reperfusion time interval of6h,12h,24h,48h,72h,7d after brain ischemia,with sixteen rats in each subgroup.After the successful of cerebral ischemia model,the treatment groups were given Butylphthalide at dose of60mg/kg/d by intragastric administration.The other groups were given the corresponding dose of consumption of peanut oil. At the expected time points rats in each group were respectively conducted the neurological deficit scores, the pathological changes was observed by HE staining, the infarct sizes were measured with TTC staining, detected the number of apoptotic cells by TUNEL.the expresion of Caspase-3and PDCD-5was detected with Immunohistochemical.Result:The rats of the sham operation group showed no obvious neurological deficit symptoms;and the others of the model group and the treatment group were seen to varying degrees of neurological deficit symptoms.The neurological deficit scores in both the model group and the treatment group reached a peak at the second day before decreasing.At a same time neurological deficit symptoms were milder in treatment group compared with model group andscores were lower, the difference was significant (P<0.05)(except for the6th hour). The rats in sham group have no infarct, with very few apoptotic cells, occasional Caspase-3, or PDCD-5positive cells. After cerebral ischemia and reperfusion, the percentages of infarct volume in model group and treatment group gradually increased,and both reached a peak at the second day and the third days respectively,then decreasing.TTC staining showed that at a same time model group have a clear and narrower boundary of the infarct formation,and the percentages of infarct volume in model group were lower, the difference was significant (P<0.05),except for the6th hour. At a same time Density of apoptotic cells and optical density of both Caspase-3and PDCD-5in treatment group are lower than model group,the difference was statistically significant (6th is excepted)(P<0.05). Caspase-3and PDCD-5positive cells were mainly distributed in the ischemic penumbra,the same as apoptotic cells. Positive correlation (r=0.74, P<0.05) can be found on optical densities between Caspase-3and PDCD-5.Conclusion:Butylphthalide soft capsules can protect the injury in rats after cerebral ischemia and reperfusion,improve the symptoms of neurological deficit after cerebral ischemia reperfusion injury, reduce the infarct volume, inhibition of apoptosis. Inhibition of apoptosis is one of the mechanisms of the neuroprotective effect of butylphthalide soft capsule. Initially confirmed,it inhibited the expression of PDCD-5, so that the Caspase-3expression reducted, and cells saved. PDCD-5may be the role of one of the targets in the neuroprotective mechanism of Butylphthalide.