电针对慢性应激抑郁模型大鼠海马突触可塑性蛋白的影响

The effect of electroacupuncture on synaptic plasticity protein in hippocampus of chronic stress depression model rats

目的:探讨电针对慢性应激抑郁模型大鼠海马突触性蛋白表达的影响,明确其治疗机制。方法:48只SD大鼠随机分为4组:对照组、模型组、电针组、氟西汀组,除对照组外,各组均采用慢性不可预见性温和应激(CUMS)建立抑郁动物模型。电针组于每日应激前选取百会、印堂两穴进行电针治疗,每天1次;氟西汀组于造模前通过灌胃给予阳性药氟西汀水溶液,剂量为10 mg/kg,持续21 d。于应激造模后7、14、21 d分别采用旷场测试和强迫游泳实验评价大鼠的抑郁样行为,Golgi染色观察海马突触结构的病理特点,Western blot检测海马突触可塑性相关蛋白SYN、PSD-95、CREB、BDNF的表达。结果:与对照组比,模型组大鼠7 d时强迫游泳不动时间显著增加(P<0.05),14 d时旷场自主活动评分显著下降(P<0.05),抑郁样行为明显,海马突触结构损伤,突触可塑性蛋白SYN、PSD-95、CREB、BDNF表达均显著下调(P<0.01);经电针治疗后,大鼠抑郁样行为得以明显改善(P<0.01),树突棘形态及数量趋于正常,SYN、PSD-95、CREB、BDNF表达均明显回升(P<0.01)。结论:电针能显著改善慢性应激抑郁模型大鼠的抑郁样行为,其机制与改善突触结构,上调突触可塑性蛋白表达有关。

Objective:To investigate the effects of electroacupuncture on the expression of synaptic protein in hippocampus of chronic stress depression rats,and to clarify its therapeutic mechanism.Methods:Fortyeight SD rats were randomly divided into 4 groups:blank control group,model group,electroacupuncture group and fluoxetine group.In addition to the control group,chronic unpredictable mild stress(CUMS)was used to establish a model of depression.The electroacupuncture group was treated with electroacupuncture once a day at the two points of“Baihui”and“Yintang”before daily stress;the fluoxetine group was given a positive drug fluoxetine solution before the modeling,with the dose of 10 mg/kg for 21 d.On the 7th,14th and 21st day of stress modeling,the depression-like behaviors of rats were evaluated by open field test and forced swimming test.The pathological features of hippocampal synaptic structure were observed by Golgi staining.The hippocampal synaptic plasticity protein SYN,PSD-95,CREB and BDNF was detected by Western-blotting test.Results:Compared with the control group,the forced swimming time of the model group was significantly increased at 7 d(P<0.05),and the spontaneous activity of the open field was significantly decreased at 14 d(P<0.05),and the depression-like behavior was obvious.The structural damage,synaptic plasticity protein SYN,PSD-95,CREB,BDNF expression were significantly down-regulated(P<0.01);after electroacupuncture treatment,the depression-like behavior of rats was significantly improved(P<0.01),dendritic spine morphology The number of SYN,PSD-95,CREB and BDNF increased significantly(P<0.01).Conclusion:Electroacupuncture can significantly improve the depression-like behavior of chronic stress-depressive rats,which is related to the improvement of synaptic structure and up-regulation of synaptic plasticity protein expression.