The Research Of Acupuncture Intervening In Cerebral Ischemia Model Rats By Regulating MAPK/ERK Pathway

Cerebrovascular disease is one of the major diseases,which is a serious hazard to human health.In our country,cerebrovascular disease rank the first three leading causes of death.Ischemic cerebrovascular disease are frequently-occurring and common diseases of mankind,So to find effective treatment,and to explainits mechanism is still the current research in the field of brain science hotspots.In recent years,the study of cerebrovascular disease found that at different stages of post-stroke rehabilitation,the organizational structure and functions of the brain can occur a certain capacity of self-repair and reconstruction.After cerebral ischemia in a few minutes to several months,the cerebral cortex have Significant changes in function and structure,and this change which is called plasticity of the brain occurred not only around in the lesion,but occurred in remote areas.Ischemic brain damage is the most common nerve injury type,and the synapse is the site of transmission and processing of information between the neurons,the function and structure of synapse have significant changes in plasticity with the external stimuli or environmental factors,therefore the synapse is the key part of activity-dependent plasticity changes in brain structure. Extracellular signal regulated kinase,a type of Mitogen activated protein kinases,is a very conservative signal systems that exist in a variety of cells from yeast tomammals.At present,it is more clearly for the research of ERK, and ERK regulate cell proliferation,differentiation and survival.on the one hand to accept from a large number of growth factor,mitogen,environmental stimulation signal,on the other hand,ERK acting on the nuclear transcription factor,regulating gene expression.At present,the search has begun for the ERK pathway in various aspects of the regulatory mechanism for the regulation of signal transduction of the way so as to achieve the purpose of treating disease.Objective To find out the related mechanism,characters,factors and rules between MAPK/ERK pathway and neuronal damage after cerebral ischemia,and to find the effect of electro-acupuncture intervention,provide new foundation to the research of treating cerebrovascular disease by acupuncture and improving the plasticity of brain function.Methods 90 SPF-grade male SD rats were selected and by the drawing method were randomly divided into sham operation group,model group and electro-acupuncture group.Sham-operated group,model group and EA group,each group was divided into 2h(hours),1d(day),3d(days) group,three time period, and a total of 9 groups,10 rats per group.We simulated clinical cerebral syndromes,selected the middle cerebral artery occlusion rat model,used the clinical commonly used electro-acupuncture by acupuncture and electrical stimulation combined,which had determined the effect on cerebral ischemia and sequelae of cerebral ischemia,and treated the focal cerebral ischemia.For the key question of the role of channels and mechanim of ERK pathway in cerebral ischemia,from the multi-link,multi-level,multi-target,we observed the response to electro-acupuncture on ERK pathway and the promoted the role of electro-acupuncture on protective effect of hippocampal neurons in cerebral ischemia.Using "Baihui" and "Dazhui" two points,from the start synapses in hippocampal neurons in area CA1 and CA3,by the way of immunohistochemical and immunofluorescence,we observed cerebral ischemia and the expression after using electro-acupuncture of dynamic changes of ERK1/2,NMDAR1,and AMPA(GluR1) receptors,which is closely related to synaptic plasticity and through the Y maze to testing the learning and memory of rats and the score on the neurological behavior of rats,we had a objective evaluation on models and the results of acupuncture intervention.Thus we deeply reserched the mechanism of acupuncture to promote the protection of neurons of the brain,the role of channels and mechanim between the MAPK/ERK pathway and in early cerebral ischemia the possible mechanism of synaptic plasticity in order to further clarified the plasticity in the brain mechanisms of neurobiology,and provided more exact theory for clinical more good improvement in brain function after cerebral ischemia.Results 1.Neurological signs scoreThe data is analyzed by Spss13.0 statistical,and homogeneity of variance test is P＞0.05,so we use LSD and the S-N-K test to analyze.Sham-operated rats neurobehavioral performance are normal,score of 0 points.Neurological rats showed that the model group,there is no comparison between the two groups statistically significant(P＞0.05),and the acupuncture group 1d and 3d group also have no statistically significant(P＞0.05),however,electroacupuncture group 1d and 3d,respectively,compare with electroacupuncture group 2h are significantly different(P＜0.01).Electroacupuncture 1d group and model 1d group(P＜0.05),electroacupuncture 3d group and model 3d group are between(P＜0.01) differences in comparison.2.Detection of Y maze learning ability in ratSham-operated rats by electrical stimulation of non-security zone from running to a safe area to spend some time in various time periods are used in at least,having significant respectively compared with another groups(apart from electro-acupuncture group 3d)(P＜0.01).the model group is no comparison between the two groups statistically significant(P＞0.05),however between electro-acupuncture groups,1d group compare 2h group with difference(P＜0.05),3d group compare 3h group with difference(P＜0.01),but 1d group compare 3d group with no difference(P＞0.05).Between electro-acupuncture groups and model groups, lectroacupuncture 1d group and 3d group all have statistically significant with model groups,but electro-acupuncture 2h group compare model 2h group with no difference(P＞0.05).3.Hippocampal P-ERK1/2 expression in ratSham-operated group is without p-ERK1/2 positive cells.IOD expression of CA1 area and CA3 area of the electro-acupuncture groups are lower than the expression of model groups,the IOD expression of electro-acupuncture 2h group and modle group 2h are higher than group 1d and group 3d,compared with statistically significant(P＜0.05).electro-acupuncture 2h group,1d group,3d group compare model 2h group,1d group,3d group with difference(P＜0.05). electro-acupuncture groups and model-groups have differences in the corresponding group(P＜0.05).That shows electro-acupuncture at an early stage can reduce p-ERK1/2 expression,which may be the role of neuronal protection.4.Hippocampal NMDAR1 expression in rat IOD expression of electro-acupuncture groups are lower than model groups,and all And have a downward trend,electro-acupuncture 2h group,1d group,3d group compare model 2h group,1d group,3d group with difference(P＜0.05) electro-acupuncture 2h group compare electro-acupuncture 1d group,3d group with difference(P＜0.01).model 2h group and model 3d group compare with difference(P＜0.01).This illustrates that electro-acupuncture at an early stage can decrease the expression of NMPAR1.IOD(SUM) expression of electro-acupuncture groups and model-groups have differences in the corresponding group(P＜0.05).5.Hippocampal AMPA(GluR1)expression in ratIOD expression of electro-acupuncture groups are lower than model groups,and all And have a downward trend,electro-acupuncture 2h group compare model 2h group with differences(P＜0.01).electro-acupuncture 1d group,3d group compare model 1d group,3d group with differences(P＜0.05) electro-acupuncture 2h group compare electro-acupuncture 1d group,3d group with difference(P＜0.01).model 2h group and model 3d group compare with difference(P＜0.01) This illustrates that electro-acupuncture at an early stage can decrease the expression of GluR1.electro-acupuncture groups and model-groups have differences in the corresponding group(P＜0.05).conclusionsThrough the observation of neurological function score that this experimental model was successful,this illustrates that Electroacupuncture can promote the role of significant improvement,on cerebral ischemia in rats with symptoms of nerve defect.At present,MAPK/ERK signaling pathway in the mechanism of cerebral ischemic injury study more,but after cerebral ischemia on synaptic plasticity rarely reported.In this study,through the expression of MAPK/ERK signaling pathway by electroacupuncture intervention,we observe the role of channels and mechanim of ERK pathway in cerebral ischemia and the expression of NMDA receptors and the AMPA receptors closely related toCerebral ischemic injury,the neuro transmitter,which are LTP,an important form of synaptic plasticity,required in the generation and maintenance,thus we can expound the relationship between the MAPK/ERK signaling pathway and cerebral ischemia,and explore its relevant mechanism by electro-acupuncture interventions.This study found that two hours after cerebral ischemia,CA3 area of the expression of phosphorylated ERK was significantly increased,but the expression of one-day group and three-day group continuously reduce,and CA1 than CA3 area is weak expression,this may be related to two areas of different tolerance to ischemia-induced,and the expression of NMDA receptor, AMPA receptor and phosphorylated ERK are in line,this shows that MAPK/ERK signaling pathway in the expression of cerebral ischemia may be related to the expression of NMDA receptor and AMPA receptor,However,the expression them in the hippocampus but not the same district.After electro-acupuncture interventions,all indexes lower than those inmodelgroup,this prompted:1. Electro-acupuncture can control and interfere with MAPK/ERK signaling pathway in the early cerebral ischemia,which may have be neuronal toxicity,and play a role of protecting the brain 2.We have examined the MAPK/ERK signaling pathway in the mechanism of cerebral ischemia,which May be mainly through the activation of MAPK/ERK signaling pathway,make it easier for NMDA and AMPA excited,thus have a toxic effect on neurons.3.NMDA and AMPA receptors is the important neurotransmit of the generation and maintenance of LTP,the activation of MAPK/ERK signaling pathway in the early Cerebral ischemia and the high expression in NMDA and AMPA receptor may be have an important impact on the reconstruction of the synaptic of the late survival of the neurons.Innovation in this topic:1.In Cerebral ischemia model rats for the first time we systematic observated the effect of acupuncture intervention in the MAPK/ERK pathway,and for clinical treatment of cerebral ischemia disease provided a new theoretical basis.2.we observed the expression of the NMDA and AMPA receptors closely related to synaptic plasticity,in the acute phase of the cerebral ischemia,their high expression in addition to the toxic effects on generated neurons,may also have a pathological synaptic plasticity,at the same time EA can inhibit this effect,and for the mechanism of the early synaptic reconstruction provides a new way of thinking.