Study On Anti-depression Mechanism Of Electro-acupuncture Based On Purinergic System

Objective:In this study,rats with depression model of chronic unpredictable mild stress(CUMS)were used as research objects to explore the anti-depression effect of electro-acupuncture from a behavioral perspective,with purinergic signaling pathways as the starting point.The expression levels of purinergic neurotransmitters,receptors and metabolic enzymes were discussed to explore the possible mechanism of electro-acupuncture in anti-depression,which provided theoretical basis and clinical application basis for electroacupuncture treatment of depression.Methods: 48 SPF male SD rats were selected,12 were randomly selected as blank group,and the remaining 36 rats were modeled by CUMS method for 28 days.After the model was prepared successfully,the rats were divided into model group by checking the random number table,electro-acupuncture group and fluoxetine group,with 12 rats in each group.The rats in each group were subjected to corresponding intervention for 14 days while CUMS modeling was maintained.electro-acupuncture group selected "Baihui","Neiguan","Sanyinjiao" points for electro-acupuncture treatment;Fluoxetine group was given fluoxetine intragastric administration(dose: 1.8mg/kg,concentration:0.18mg/ml).General observation,sucrose preference test and open field experiment were conducted before,after modeling and after the experiment.After the experiment,the contents of ATP,AMP,adenosine and inosine in the cerebrospinal fluid of rats were detected by enzyme-related immunosorbent assay.Immunohistochemistry was used to detect the differences in the expression of purinergic P2X7(Purinergic P2 X,ligand-gatedion,P2X7),adenosine receptor(AR)A1 and A2 A positive neurons in hippocampal brain region of rats in each group.The protein expression levels of CD39,5’-nucleotide enzyme(CD73),adenosine deaminase(ADA)and adenosine kinase(ADK)in hippocampal brain region of rats in each group were detected by Western blot.Finally,collect data for statistical analysis and draw conclusions.Results:1.Effects of CUMS on body weight and behavioral indexes in ratsBefore modeling,the baseline levels of weight,sucrose preference(%),horizontal activity distance and vertical activity times of all rats were basically the same(P > 0.05).After 28 days of modeling,weight,sucrose preference(%),horizontal activity distance and vertical activity times of all rats were significantly lower than before modeling(P < 0.001).2.Comparison of body weight and behavioral indexes in each groupCompared with blank group,weight,sucrose preference(%),horizontal movement distance and vertical movement times of rats in model group were significantly decreased(P < 0.01,P < 0.001,P < 0.001,P < 0.001).Compared with model group,weight,sucrose preference(%)and vertical movement distance of rats in electro-acupuncture group and fluoxetine group were significantly increased(P < 0.01).There was no significant difference in behavioral indexes between electro-acupuncture group and fluoxetine group(P > 0.05).3.Comparison of the expression of ATP,AMP,adenosine and inosine in cerebrospinal fluid of rats in each groupCompared with blank group,the expression of ATP,AMP,adenosine and inosine in CSF of rats in model group were significantly decreased(P < 0.001).Compared with model group,the expression of ATP,AMP,adenosine and inosine in cerebrospinal fluid of rats in electro-acupuncture group were significantly increased(P < 0.05,P < 0.01,P < 0.01,P < 0.05).Inosine only expression in cerebrospinal fluid of rats in fluoxetine group was significantly increased(P < 0.01).4.Comparison of the expression of P2X7 R,A1R and A2 AR in the hippocampus of rats in each groupCompared with blank group,the expressions of P2X7 R and A2 AR in hippocampus of model group were significantly increased(P < 0.01,P < 0.001).The expression of A1 R was significantly decreased(P < 0.001).Compared with model group,the expressions of P2X7 R and A2 AR in the hippocampus of rats in electro-acupuncture and fluoxetine groups were decreased(P < 0.05,P < 0.01),while the expression of A1 R was significantly increased(P < 0.01,P < 0.05).However,there were no significant differences in the expression of P2X7 R,A1R and A2 AR in the hippocampus between the two intervention groups(P > 0.05).5.Comparison of the expression of CD39,CD73,ADA and ADK in hippocampal area of rats in each groupCompared with blank group,the expression of CD39,CD73 and ADK in hippocampus of rats in model group were significantly increased(P < 0.001),and the expression of ADA protein was decreased(P < 0.01).Compared with model group,the expressions of CD39,CD73 and ADK in hippocampus of rats in electro-acupuncture group were significantly decreased(P < 0.01,P < 0.01,P < 0.05),and the expression of ADA was increased(P < 0.05).Only the expressions of CD39 and CD73 were decreased in fluoxetine group(P < 0.001,P < 0.05).Conclusion:1.Electro-acupuncture at Baihui,Neiguan and Sanyinjiao points can improve the depression-like behavior of CUMS model rats,and its effect is similar to fluoxetine;2.The antidepressant effect of electro-acupuncture was related to the increased expression of ATP,AMP,adenosine and inosine in the cerebrospinal fluid of depressed rats.3.Electro-acupuncture can effectively inhibit the overexpression of P2X7 R,A2AR,CD39,CD73 and ADK proteins in the hippocampus of depressed model rats,while promote the expression of A1 R and ADA.