Effects Of Electroacupuncturing Ren Meridian On Growth Factor Expression After Focal Cerebral Ischemia-Reperfusion In Rats

Cerebral Ischemic Stroke(CIS),which is also called Cerebral Infarction(CI), is the infarction of brain tissue duing to Cerebral artery occlusion, accompannied with damage of neuron,astrocyte and oligodendrocyte.It is the most important event of central nervous system causing death and mutilation in modern society.Acupuncturing Ren Meridian has clinic foundation on treating CIS.Research discovered that electroacupuncturing Ren Meridian could promote the proliferation and diffrentiation of Nerve Stem Cells which profit the recovery of nerve after cerebral ischemia.Also,we found the effect was related with the activation of ERK signal transduction path.Thus,we assumed that electroacupuncturing Ren Meridian could generate some upstream element which was ERK path dependency,and the up-regulation of these factor would active mechanism of nerve recovery to promte the recovery of cerebral neuron.Based on the assumption and literature study,we chose the endogenous growth factor in brain as cut-in point.By the way of studying on literature and experiment,we can approach the possible mechanism of electroacupuncturing Ren Meridian on treating CIS.Objective:To observe the change of bFGF/EGF/NGF in subventricular zone(SVZ) and Denatate Gyrus(DG) after Cerebral ischemia-reperfusion in Rats,And approach the effects of electroacupuncturing Ren Meridian on the three growth factor.By the observation of growth factor,we could find the possible mechanism of electroacupuncturing Ren Meridian on treating CIS,and provide theory and experiment evidence for acupuncturing to treat CIS. Methods:A total of seventy-two adult SD rats from SPF-grade laboratory were taken into the study.Before the test,they were raised to adapt to the surroundings.According to the random digits table,they were divided into sham operation group(Sham),MCAO group(MCAO) and Electroacupuncture Ren Meridian group(R).Each group was averagely divided into 7 days group,14 days group and 28 days group at random.There were eight rats in each subset group. Before operation,rats were abrosia for twelve hours,and Cerebral ischemia-reperfusion injury model was induced by the method of nylon monofilament embolism.After that,We observed the nerve function score and death rate of MCAO rats.Rats in R group were treated with electroacupuncturing Chengjiang/Qihai/Guanyuan points twenty-four hours after operation.As for electric acupuncture,distant-dense wave was chosen.The frequency was15Hz for dense wave and intensity was 6 to15V.The treatment lasted for twenty minutes,and was done once every day until the rats killed.On the other hand, rats in Sham group and MCAO group were fixed on the operation board without any treatment for twenty minutes twenty-four hours after operation.Rats of each group were killed at the design time,and their brain were taken immediately.Then we observed the pathomorphism of corpora striata and hippocampus in ischemic brain of MACO rats by HE stain.Immunohistochemistry was used to detect the protein expression of bFGF/EGF/NGF in SVZ and DG of MCAO rats.In situ hybridization was used to detect the mRNA expression of bFGF/EGF/NGF in SVZ and DG of MCAO rats.At last,we counted positive cells at light microscope of 200×,analyzed the image by analytical system of Leica DC software from German,and compared the difference between groups by SPSS 13.0 software.Results:1.Electroacupuncturing Ren meridian had little effection on the Nerve function score and death rate of MCAO rats.2.Corpora striata and hippocampus shew obvious brain edema and nerve cell degeneration after focal cerebral ischemia-reperfusion,which shew the Cerebral ischemia-reperfusion injury model was formed successfully.Compared with MCAO group at the same time after focal cerebral ischemia-reperfusion,R group could relieve the degree of injury.3.After focal cerebral ischemia-reperfusion,protein and mRNA expression of bFGF in SVZ and DG shew an increase which could not last for long time.With the extend of time after focal cerebral ischemia-reperfusion,the positive expression of bFGF shew a tendency of decrease.At the time of 7 days after reperfusion,positive expression was maximum;at the time of 14 days after reperfusion,positive expression decreased;and at the time of 28 days after reperfusion,the positive expression decreased to basic level.Electroacupuncturing Ren meridian could at least increase the protein and mRNA expression of bFGF at the time of 14 days after reperfusion.4.After focal cerebral ischemia-reperfusion,protein and mRNA expression of EGF in SVZ and DG shew an increase which could not last for long time.With the extend of time after focal cerebral ischemia-reperfusion,the positive expression of EGF shew a tendency of decrease.At the time of 14 days after reperfusion,the protein expression decreased to basic level,while the mRNA expression decreased to basic level at the time of 28 days after reperfusion.That is to say,the protein and mRNA expression of EGF was asynchronous.Electroacupuncturing Ren meridian could at least increase the protein expression of EGF at the time of 7 days after reperfusion,and could at least increase the mRNA expression of EGF at the time of 14 days after reperfusion.5.After focal cerebral ischemia-reperfusion,protein and mRNA expression of NGF in SVZ and DG shew an increase which could not last for long time.With the extend of time after focal cerebral ischemia-reperfusion,the positive expression of NGF shew a tendency of decrease.At the time of 7 days after reperfusion,positive expression was maximum;at the time of 14 days after reperfusion,positive expression decreased;and at the time of 28 days after reperfusion,the positive expression decreased to basic level.Electroacupuncturing Ren meridian could at least increase the protein expression of NGF at the time of 14 days after reperfusion,and could at least increase the mRNA expression of NGF at the time of 28 days after reperfusion.Conclusions:BFGF/EGF/NGF participate the process of pathomorphism after ischemical reperfusion injury.Electroacupuncturing Ren meridian can increase the expression of BFGF/EGF/NGF after focal cerebral ischemia-reperfusion.By this way,nerve can be protected and damage is recovered.