The Impact Of EA-Pretreatment On "BAIHUI"、"TAICHONG" In Different Durations On VEGF、MMP-9in Blood-Brain Barrier After Cerebral Ischemia-Reperfusion Injury In Rats

Objective To explore the impact of EA-pretreatment in different durations on VEGF、MMP-9in blood-brain barrier(BBB) after cerebral ischemia-reperfusion injury in ratsMethod (1) Experimental classification and method:64SD rats were randomly divided into four groups:sham-operated group, model group,EA-pretreatment groups for7days and15days(16rats in each group). The management of each group as follows:Model group was operated to be MCAO model with reference to Zea Longa reforming longa method; Sham-operated group was operated to separate carotid artery without line embolism; EA-pretreatment groups for7days and15days were molded after EA-pretreatment for7days and15days. Rats in EA-pretreatment groups were punctured on " BAIHUI "" TAICHONG ". Each acupoint was connected to HANS electric acupuncture apparatus for30minutes with2/15Hz frequence, and1mA electric current per day. All groups were molded to be MCAO model24h after the last EA-pretreatment. The reperfusion was operated90min after ischemia. The brains in EA-pretreatment groups and model group were removed24h after reperfusion, which were removed with the same method in sham-operated group24h after surgery.(2)The cerebral blood flow monitor by Laser Doppler:the Laser Doppler was used to monitor rats’local cerebral blood flow before and after molding, which was also used after reperfusion. After Zea Longa molding, the rats’local cerebral blood flow was monitored immediately(the molding standard went by immediate local cerebral blood flow reducing to45±10%less than the normal).(3) Index detection:①The detection of MMP-9in BBB:immunohistochemical method was applied to detect the number of MMP-9positive cells in BBB in each group; the expression of MMP-9mRNA in BBB in each group was detected by fluorescence quantitative PCR.②The detection of VEGF in BBB:the expression of VEGF-mRNA in BBB in each group was detected by fluorescence quantitative PCR.Result:①The MMP-9positive cells in BBB in sham-operated group was weakly positive. The distribution level of MMP-9positive cells in BBB in model group was higher than sham-operated group obviously (P<0.001).Compared with model group, the number of MMP-9positive cells in BBB in EA-pretreatment groups for7days were significantly decreased (P<0.01). Compared with model group, the number of MMP-9positive cells in BBB in EA-pretreatment groups for15days were decreased significantly (P<0.01). And the level was significantly different in EA-pretreatment group for7days and15days (P<0.01)②Compared with Sham-operated group, the expression of MMP-9mRNA in BBB in model group was increased significantly (P<0.001). Compared with model group, the expression of MMP-9mRNA in EA-pretreatment groups for7days and15days was significantly different (P<0.01) The expression level of MMP-9mRNA in EA-pretreatment groups for15days is significantly different from7days (P<0.01).③The expression level of VEGF-mRNA in model group was higher than sham-operated group (P<0.001).Compared with model group, the expression of VEGF-mRNA in EA-pretreatment groups for7days and15days were significantly different (P<0.01), and EA-pretreatment group for7days and15days were significantly different (P<0.05)Conclusion:①EA-pretreatment for7and15days could both restrain the distribution of MMP-9in BBB in cerebral ischemia-reperfusion rats and the expression of MMP-9、 VEGF-mRNA in BBB. The effect of EA-pretreatment for15days is the best②That EA-pretreatment protects BBB during cerebral ischemia-reperfusion is probably related to the down-regulated expression of VEGF and MMP-9after ischemia.