Effect Of Electroacupuncture On Amyloid Protein Deposition And Ultrastructure Of Hippocampus In AD Rats And The Mechanism Of Acupuncture

Objective:Observe the behavior change of rats,the contents of A?scavenging related enzymes and A?_1-42-42 in serum and the expression of A?scavenging related enzymes and A?_1-42-42 in hippocampus of rats,and ultrastructural changes in hippocampus of rats,to explore the mechanism of A?scavenging related enzymes in Alzheimer's disease and the effect of interference with electroacupuncture on A beta scavenging.In order to provide new experimental evidence for acupuncture treatment of AD.Methods:All rats were screened by Morris water maze before modeling,and the eligible Wistar male healthy rats were randomly divided into normal group,sham operation group,model group and EA group?electroacupuncture group?,with 20 rats in each groups.The model of AD?Alzheimer's disease?was prepared by injection of 5?L A beta 1-42 into the bilateral hippocampus of rats under stereotaxic apparatus,and the sham operation group was injected with equal amount of saline.No treatment was given in the normal group,model group and sham operation group,While the rats in EA group were treated with electroacupuncture with five hertz continuous wave at Baihui and bilateral Shenshu points,the therapy was given 15 minutes each time,and one times a day,and the group was treated continuously for 15 days.After the end of the treatment,?1?Using Morris water maze to detect the learning and memory ability of rats in each group;?2?Using the ELISA method,Western-Blot method to measure the levels and expressions of A beta1-42,IDE,TTR,and alpha 2M in serum and hippocampus of rats in each groups;?3?Using immunohistochemical method to observe the expression of A beta 1-42 in hippocampus of rats in each groups;?4?Using transmission electron microscopy to observe changes in the ultrastructure of AC?astrocytes?and neurons in the hippocampus of rats.Results:?1?Morris water maze test results:Compared with sham operation group,the escape latency was significantly prolonged,effective time was significantly shortened,the number of crossing platform position was significantly reduced in model group,?P<0.01?;compared with the model group,the escape latency was significantly shortened,effective time was prolonged,the number of crossing platform position increased significantly in EA group?P<0.05,P<0.01?.?2?ELISA test results:Compared with sham operation group,the content of insulin degrading enzyme?IDE?,transthyretin?TTR?and alpha 2 macroglobulin??₂M?in serum was decreased significantly in rats of the model group?P<0.05,P<0.01?,while the content of A beta 1-42 was significantly increased?P<0.01?;compared with the model group,the content of IDE?TTR and?₂M in serum was increased significantly in rats of the EA group?P<0.05,P<0.01?,while the content of A beta 1-42 was significantly decreased?P<0.05?.?3?Immunohistochemistry test results:Compared with sham operation group,the positive expression of A beta 1-42 increased in the dentate gyrus of rats in the model group?P<0.01?.Compared with the model group,the positive expression of A beta 1-42 in the dentate gyrus of the EA group decreased?P<0.05?.?4?Western-Blot test results:Compared with the sham-operation group,the expression of IDE?TTR and?₂M in the hippocampus was significantly decreased?P<0.05,P<0.01?,the expression of A?_1-42 was significantly up-grated?P<0.01?;compared with the model group,the expression of IDE?TTR and?₂M in the hippocampus was significantly up-grated?P<0.05,P<0.01?,the expression of A?_1-42 was significantly decreased in electroacupuncture group?P<0.01?.?5?Transmission electron microscope test resuits:Neurons:In the normal group and the sham operation group,the morphology of the neurons was complete,the structure was clear,the arrangement was neat.The number of organelles was more and the shape was normal,and the structure was clear.In the model group,the volume of neurons was reduced,the morphology was extremely irregular,the nucleus was severely contracted,the cytoplasm was seriously edematous,the heterochromatin color was deepened,the number of organelles decreased significantly,the endoplasmic reticulum expanded and degranulation,mitochondria swelled and deformed obviously,and the number decreased.In the electroacupuncture group,the morphology of the neurons was basically regular,the nucleus was fixed,the cytoplasm edema was serious,the number of organelles decreased,and the mitochondria were slightly swollen.Astrocytes:In the normal group,the nucleus of astrocytes was obvious,the organelle was rich,the axon was obvious,the organelle was normal and the structure was clear.In the sham operation group,the nucleus of astrocytes was obvious,the nucleolus was clear and round,and the cytoplasm contained abundant organelles and the morphology was normal and the structure was clear.In the model group,there were severe edema around astrocytes,less cytoplasm,rare organelles in the cytoplasm,severe swelling of mitochondria,and mild endoplasmic reticulum dilation.The peripheral edema of astrocytes in the EA group was serious,and a small amount of mitochondria and vacuoles were found in the cytoplasm.The swelling of mitochondria was obvious,and the endoplasmic reticulum was slightly dilated.Conclusion:Electro acupuncture treatment can increase the content and expression of A beta clearance related enzymes in serum and hippocampus of AD rats,promote the degradation of A beta,reduce the deposition of A beta,and improve the ultrastructure of hippocampus,thereby delaying or improving the pathological process of AD and improving learning and memory ability of AD rats.