The Mechanism Study Of Buyanghuanwu Decoction On The Ability Of Learning And Memory Of Vascular Dementia Rats

Brain is sensitive to ischemia and hypoxia.And repeated cerebral ischemia-reperfusion injury and long-term slow-Low perfusion are the main reasons to trigger vascular dementia, becoming important factors of ontraining ecovery of ischemic cerebro vascular disease. So it is necessary to explore the pathophysiological mechanisms of cerebral ischemia-reperfusion injury and to strengthen its prevention and treatment.Hippocampal CA1 area is considered to be an important part of the Memory and learning and also one of the most sensitive areas to ischemia and hypoxia. extracellular signal-egulated kinase-2 can control the growth,development,differentiation and protection of hippo- ampal neurons in the development of ischemic cerebrovascular disease. What's more, ERK2 could change the dendrites state of hippocampal Cells, stalk out the new dendritic spines and participate in the of plastic in neuron morphology.Calcium/calmodulin-dependent protein kinase II is an important target enzyme, is the most abundant of protein kinase in brain, is high expression in the postsynaptic density (PSD) of hippocampus and cerebral cortex that can catalyze phosphorylation of a variety of proteins Which lead to a series of biochemical reactions of downstream. CaMKII is also a kind of structural proteins. And CaMKII signal transduction pathways are regarded as the major components of receptor plasticity,learning and memory and so on. long-term-potentiation is able to objectively reflect the situation of synaptic plasticity.CaMKIIβchanges has been fewerly reported in schemia- perfusion injury in the respect of pathological physiological processes of rats combined with learning and memory defects in vascular dementia buyanghuanwu decoction is the common and classic prescription to cure cerebral schemia-reperfusion njury.But how buyanghuanwu decoction function is not fully clarified. Therefore,we are to explore the buyanghuanwu decoction's molecular mechanism of improving learning and memory by observing the effect of buyanghuanwu decoction on the expression of ERK2 and CaMKIIβprotein and the changes of LTP in the Hippocampus CA1 area of VD rats.The first partThe effect of buyanghuanwu decoction on ethology of vascular dementia rats and morphology of neurons in hippocampus CA1 areaAIMTo observe the effects of Buyanghuanwu decoction on behavior of vascular dementia rats and morphology of neurons in hippocampus CA1 region.MethodsThe rats were divided into 4 groups: sham operation group,model group,buyanghuanwu decoction group and nimodipine group. The VD rats model were prepared by Pulsinelli's four-vessel occlusion.Buyanghuanwu decoction (50g/kg/d) and nimodipine (20mg/kg/d) were given by intragastric administration for 30 days, Rats behavior were tested by Morris water maze 28 days post-operation. 30 days post-operation, The morphology changes were observed by HE staining in hippocampal CA1 area.ResultsMorris water maze show: comparing with sham operation group rats, the escape latency of rats in model group had obviously extended (P<0.05), the times of crossing the platform had decreased obviously (P<0.05). Compared with model group, the escape latency of rats in buyanghuanwu decoction group and nimodipine group had obviously shortened(P<0.05) and the times of crossing the platform had increased obviously (P<0.05).HE staining: The neurons in hippocampus CA1 area of VD rats in model group appeared significantly pathological changes, irregular arrangement,coagulation necrosis and obvious deletion.the number of neurons in hippocampal CA1 area had significantly reduced (P<0.05); Comparing with model group, pathological changes of the neurons in BYHWD group and nimodipine group hippocampal had significant improved.The neurons were in neat rows, integral structure and close to sham operation group'. the number of neurons in hippocampal CA1 area had significantly increased(P<0.05). ConclusionsBuyanghuanwu decoction can improve VD rats'ability of learning and memory and protect neurons from ischemia-reperfusion injury.The second partThe effect of buyanghuanwu decoction on expression of LTP in rain tissue of hippocampal CA1 area of vascular dementia ratsAIMTo observe the effect of buyanghuanwu decoction on expression of LTP in hippocampus CA1 area. METHODS: The methods of group dividing and model making were the same as the first part. Used Hippocampal CA3-CA1 Area Records Method to record LTP in hippocampal CA1 area.RESULTSComparing with sham operation group, LTP expression in hippocampus CA1 area decreased significantly in the model group (P<0.05). Comparing with the model group, LTP expression in hippocampus CA1 area of buyanghuanwu decoction group and nimodipine group rats had significantly increased (P<0.05).CONCLUSIONBuyanghuanwu decoction can promote the expression of LTP in hippocampus CA1 area ,which can improve learning and memory.The third part The effect of buyanghuanwu decoction on expression of ERK2 protein in brain tissue of hippocampal CA1 area of vascular dementia ratsAIMTo observe the effect of buyanghuanwu decoction on the expression of ERK2 relating to learning and memory of VD rats.METHODSThe methods of group dividing and model making were the same as the first part. Western Blots was used to observe the expression of ERK2 protein of VD rats in brain tissue of hippocampal CA1 area.RESULTSComparing with sham operation group,the expression of ERK2 protein of model group rats in hippocampus CA1 area had significantly decreased (P<0.05). Comparing with the model group, the expression of ERK2 protein of in buyanghuanwu decoction group and nimodipine group rats in hippocampus CA1 area had significantly increased (P<0.05).CONCLUSIONBuyanghuanwu decoction can promote the expression of ERK2 protein of VD rats in hippocampus CA1 area ,which can protect hippocampal neurons and improve learning and memory.The fourth partThe effect of buyanghuanwu decoction on expression of CaMKIIβin brain tissue in hippocampal CA1 area of vascular dementia ratAIMTo investigate the effect of buyanghuanwu decoction on expression of CaMKIIβrelating to learning and memory of VD rats.METHODSThe methods of group dividing and model making were the same as the first part. Western Blots was used to observe the expression of ERK2 protein of VD rats in brain tissue of hippocampal CA1 area.RESULTSComparing with sham operation group, expression of CaMKIIβprotein of model group rats in hippocampus CA1 area had significantly decreased (P<0.05). Comparing with the model group, expression of CaMKIIβprotein of buyanghuanwu decoction group and nimodipine group rats in hippocampus CA1 area had significantly increased (P<0.05).CONCLUSIONBuyanghuanwu decoction can promote the expression of CaMKIIβprotein,which can rebuild the synapses and improve learning and memory.Conclusion1 BYHWD has a protective effect on neuronal damage of VD rats.It can improve learning and memory of VD rats.2 BYHWD can enhance the expression of LTP in Hippocampus CA1area and subsequently improve function of learning and memory of VD rats.3 BYHWD can promote the expression of ERK2 in brain tissue in hippocampal CA1 area of VD rats,which can rebuild the synapses and improve learning and memory.4 BYHWDcan promote the expression of CaMKIIβin brain tissue in hippocampal CA1 area of VD rats,enhance synaptic plasticity,which can rebuild the synapses and improve learning and memory.