The Effect Of Electroacupuncture At “sishencong” And “baihui” Acupoints On Factor Nogo-A And CaMK Ⅱexpression In Hippocampus Learning And Memory Abilities In MCAO Model Rats

Objective: We established the MCAO modle to simulate post stroke cognitive impairment(PSCI), to investigate the effect of electroacupuncture(EA) on factor Nogo-A and Ca MKⅡ expression in hippocampus, meanwhile the effect of electroacupuncture on Morris water maze(MWM) test of MCAO modle rats is also studied. and explore the mechanism of EA in the treatment of learning and memory impairment in PSCI from the macro behavior to the micro cellular and molecular level, and provide experimental basis and theoretical guidance for clinical treatment of acupuncture and moxibustion on the PSCI. Methods:(1)Object selecting and grouping: Select 84 rats without learning and memory impairment through MWM test,and randomly divided into normal group, model group,sham acupuncture group and EA group. Four group further randomly divided into 1d、7d、14d and 28 d subunit which corresponding with four different times to observe. All rats except normal group were made middle cerebral artery occlusion(MCAO) model through thread embolism method.If the successful modeling SD rats was confirmed, the next step of experiment started, if not,the MCAO modeling process was continued to supplement the number of experimental SD rats.(2)Intervention measures: The rats in normal group and model group were raised as usual, ingest, drinking freely and without any intervention except grasping at the corresponding period under the same conditions; EA group were given acupuncture and EA stimulation, EA was applied to “Baihui” and ”Sishencong” point; The acupuncture needle affixed to the acupoint and does not penetrate into the skin of mouse in Sham acupuncture group.(3) Observation index: Morris water maze test was done on the 1day, 7day, 14 day, 28 day after modeling, the indexes of more than MWM test were observed at 4 time points on 1day, 7day, 14 day, 28 day. ①The behavioral abnormalities were investigated by water maze test including the place navigation test and the spatial probe test. ② HE staining to observe the pathological changes of hippocampus of rat brain tissue after the MWM test; ③To detect the expression of Nogo-A in hippocampus of cerebral infarction side by immunohistochemistry. ④To detect the expression of Ca MKII in hippocampus of cerebral infarction side by immunohistochemistry. Analyze the average optical density of Ca MKII and Nogo-A by the image analysis system of Image-Pro Plus 6.0. To analyze the above data with the method of one-way ANOVA.(4)Statistical treatment: the measurement value by the mean and standard deviation(?x±s), the experimental data were statistically analyzed using IBM SPSS Statistics 19 software; P <0.05 was statistically significant and the P<0.01 was statistically significant; the place navigation test data by using the method of multivariate analysis of variance of repeated data, the spatial probe test data using the single factor analysis of variance; Method for analysis of disease group staining data with single factor variance; and all the data were dispose by Linear correlation analysis;All the data and analysis results by using Graph Pad Prism 5 software to map. Results:① EA group was significantly better than the model group and sham acupuncture group in place navigation test besides spatial probe test(P<0.05). Results there was no significant difference in the model group and the sham acupuncture group in the MWM test(P>0.05).② The expression of Nogo-A immunohistochemical staining results:By immunohistochemical detection of Nogo-A positive products in the average optical density value, compared with normal group and sham acupuncture group, expression of Nogo-A in hippocampus after EA 1 days treatment in EA group was significantly decreased, the difference was statistically significant(P<0.01), while model group compared with sham acupuncture group, there was no statistically significant difference(P>0.05). ③The expression of Ca MKII immunohistochemical staining results:By immunohistochemical detection of Ca MKII positive products in the average optical density value, compared with normal group and sham acupuncture group, the expression of Ca MKII in hippocampus after EA 1 days treatment in EA group was significantly decreased, the difference was statistically significant(P<0.01), while model group compared with sham acupuncture group, there was no statistically significant difference(P>0.05). ④ Linear correlation analysis showed that MWM test results and the Ca MKII expression was positively correlated, that MWM test results and the Nogo-A expression was negatively correlated, place navigation test results and spatial probe test results was negatively correlated, Nogo-A expression and the Ca MKII expression was positively correlated. Conclusion: In this study, to observe the effect of Nogo-A and Ca MKⅡ expression in hippocampus as well as learning and memory abilities after EA treatment through the production of PSCI model, the following conclusions can be drawn: 1. The MCAO model rats learning and memory decline, the MCAO model can simulate the impairment of learning and memory in PSCI rats; 2. To the MCAO model rats for EA treatment at “Sishencong” and “Baihui” acupoints can decrease the expression of Nogo-A in hippocampus, increase the expression of Ca MKII in hippocampus; 3. Efficacy of EA treatment to improve the learning and memory abilities of PSCI rats was positively correlated with the expression of Nogo-A,and negatively correlated with the expression of Ca MKII; 4. EA treatment at “Sishencong” and “Baihui” acupoints can improve the learning and memory abilities of PSCI rats; 5. The improvement of learning and memory abilities in PSCI rats by the EA treatment at “Sishencong” and “Baihui” acupoints has no correlation with the placebo effect of acupuncture; 6. The mechanism of the EA at “Sishencong” and “Baihui” acupoints can improve learning & memory ability in the PSCI rats might be associated with EA down regulated the expression of the nerve regeneration inhibitory factor Nogo-A, and up regulated the expression of the Learning & memory of molecular switch Ca MKII.