Power Against Cerebral Ischemia-reperfusion Injury In Rat Hippocampal Tissue β- Endorphin Effect

Research Objective:To observe behavior performance and (3-EP concentration in the hippocampus of cerebral ischemia reperfusion injury model rats with different intervention time of electro-acupuncture(EA), and to explore the mechanism for treatment of electro-acupuncture curing cerebral ischemia reperfusion injury.Research Methods:350adult male Sprague-Dawley (SD) rats, weighting250g-280g, were averagely divided into5batches which were separately treated in5different intervention time as follows:6h,12h, Id,3d,7d. Each batch of rats was randomly divided into5groups:EA acupoint group, EA non-acupoint group, model control group, sham operation group and normal control group. There were14rats in each intervention time.Middle cerebral artery occlusion (MCAO) models were made via surgical insertion of a nylon filament into the artery. And then the nylon filament would be pulled out to induce the reperfusion injury after2hours-insertion. According to Zea-longa’s neurological deficit scores, the model rats would be made successfully if they were evaluated to1～3scores after awaking.Interventions:①EA meridian group:make model rats with electro-acupuncture at DU20, DU16,LI11(double),ST36(double);②EA non-acupoint group:make model rats with electro-acupuncture at non-acupoints;③model control group:bundle and fix the model rats as EA group without any other interventions after making models;④am operation group: except inserting the a nylon filament, the remaining operations the same as model control group;⑤ormal control group:bundle and fix the rats as EA group without any other interventions.EA stimulation parameters were as follows:dilatational wave,2/30Hz,1mA, and the’deqi’degree-tentacles’and ears’fretting.6h,12h and1d groups that rats were modeled after6h,12h and Id, were respectively electro-acupunctured once, lasting30min.As to the rest over1day groups, they were electro-acupunctured once a day and continued electro-acupuncturing to draw materials.Each group, were measured β-EP concentration in the hippocampus of rats using enzyme-linked immunoassay (ELISA) technology, after modeling successfully and EA treatment. Using SPSS17.0software for statistical analysis, P value less than0.05was significant.Research Results:1.After cerebral ischemia and reperfusion,hippocampus β-EP levels increased significantly.2.EA DU20, DU16, LI11, ST36can significantly reduce6h,12h, Id,3d,7d group within the hippocampus P-EP,3.non-acupuncture points, in addition to7d group, can also be significantly reduced in the hippocampus of β-EP.4.Acupuncture meridian points compared to EA so that the hippocampus of non-β-EP levels decreased more significantly.5.No significant difference in the sham group and normal control group hippocampus β-EP.6.Model hippocampal β-EP levels rapidly reached a high level at6h,12h and peaked at over time1d,3d,7d gradually decreased.7.EA Meridian enables modeling rat hippocampal P-EP levels remain relatively low at6h, roughly3d,7d fairly and peaked at12h, over time,1d,3d,7d gradually decline.Conclusion:The results suggested that EA DU20, DU16, Ll11(double), ST36(double)have a specificity for curing cerebral ischemia-reperfusion injury rats.And EA non-acupoint also has some Placebo Effect.The mechanism of effect of Electroacupuncture on cerebral ischemia reperfusion injury by reducing the content of endogenous injury factor may be beta endorphin, which participate in the nerve endocrine immune network, so as to protect the cerebral ischemia reperfusion injury.