【摘要】 目的探讨电针联合经颅磁刺激对脑缺血-再灌注损伤大鼠的神经保护作用,及其可能的作用机制。方法 60只健康雄性SD大鼠随机分为假手术组、模型组、电针组、磁刺激组和联合组,每组12只,采用线栓法构建大鼠脑缺血-再灌注损伤模型,假手术组大鼠仅分离血管而不将尼龙线栓插入;成功建模24 h后,电针组大鼠进行电针治疗,用28号针分别刺入大鼠百会穴和大椎穴,连通电针治疗仪,参数设置:电压2～4 V,电流2 mA,密波30 Hz,疏波2 Hz, 1次/d, 30 min/次,连续2周。磁刺激组接受经颅磁刺激,将大鼠头部固定,磁刺激线圈紧贴着头皮,并与大鼠右大脑半球相切,参数设置:磁场峰值强度1.44 T,频率0.5 Hz, 60个磁脉冲/次,1次/d,连续2周。联合组则在电针治疗的基础上,接受经颅磁刺激。分别于成功建模24 h和16 d时,按照Longa评分标准对各组大鼠神经功能进行评分,TUNEL法检测大鼠脑缺血组织中神经元凋亡指数,Western blot法检测大鼠脑缺血组织中PTEN、Akt和p-Akt蛋白表达。结果模型组、电针组、磁刺激组和联合组大鼠在建模24 h和16 d时神经功能评分均高于假手术组(均P<0.05);与模型组比较,电针组、磁刺激组和联合组大鼠在建模16 d时神经功能评分降低(均P<0.05);与电针组和磁刺激组比较,联合组大鼠在建模16 d时神经功能评分降低(P<0.05)。与假手术组比较,模型组、电针组、磁刺激组和联合组大鼠脑缺血组织中神经元凋亡指数升高(均P<0.05),PTEN和Akt蛋白相对表达量升高(均P<0.05),而p-Akt蛋白相对表达量降低(均P<0.05);与模型组比较,电针组、磁刺激组和联合组大鼠脑缺血区组织中神经元凋亡指数降低(均P<0.05),PTEN和Akt蛋白相对表达量降低(均P<0.05),而p-Akt蛋白相对表达量升高(均P<0.05);与电针组和磁刺激组比较,联合组大鼠脑缺血组织中神经元凋亡指数降低(均P<0.05),PTEN和Akt蛋白相对表达量降低(均P<0.05),而p-Akt蛋白相对表达量升高(均P<0.05)。结论电针联合经颅磁刺激可改善脑缺血-再灌注损伤大鼠神经功能损伤,减少脑缺血组织中神经元凋亡,其机制可能与抑制脑缺血组织中PTEN蛋白表达,激活PI3K/Akt信号通路有关。更多还原

【Abstract】 Objective To investigate the neuroprotective effect of electroacupuncture combined with transcranial magnetic stimulation on cerebral ischemia-reperfusion injury in rats, and to explore the possible mechanism.Methods Sixty healthy male SD rats were randomly divided into sham operation group, model group, electroacupuncture group, magnetic stimulation group and combined group(12 in each group).The ischemia-reperfusion injury rat model was established by middle cerebral artery occlusion.Twenty-four hours after successful modeling, the rats in the electroacupuncture group were treated with electroacupuncture, 28 gauge needles were inserted into the Baihui and Dazhui points of the rat, connected with electro-acupuncture treatment instrument.Parameters was set as follows: voltage 2-4 V,current 2 mA,dense wave 30 Hz, sparse wave 2 Hz, once per day, 30 min per time, for continuous 2 weeks.The rats in the magnetic stimulation group received transcranial magnetic stimulation, head of the rat was fixed, and the magnetic stimulation coil was close to the scalp and tangent to the right cerebral hemisphere of the rat.And parameters were set as follows: peak magnetic field intensity 1.44 T,frequency 0.5 Hz, 60 magnetic pulses per time, once per day, for continuous 2 weeks.The rats in the combined group received transcranial magnetic stimulation based on the treatment of the electroacupuncture group.Twenty-four hours and 16 days after successful modeling, the neurological deficits of rats in each group were evaluated according to the Longa scoring criteria.The neuron apoptosis index in ischemic tissue of rats was detected by using TUNEL method.The expression levelss of PTEN,Akt and p-Akt proteins in ischemic tissue of rats were detected by using Western blotting.Results The neurological scores of 24 hours and 16 days after successful modeling in the model group, electroacupuncture group, magnetic stimulation group and combined group were significantly higher than those in the sham operation group(P<0.05).Compared with the model group, the neurological scores of 16 days after successful modeling of the rats in the electroacupuncture group, magnetic stimulation group and combined group were significantly decreased(P<0.05).Compared with the electroacupuncture group and magnetic stimulation group, the neurological score of the rats at 16 days after successful modeling in the combined group was decreased(P<0.05).Compared with the sham operation group, the apoptotic indexes of neurons in the cerebral ischemic tissues of rats in the model group, electroacupuncture group, magnetic stimulation group and combined group were increased(P<0.05),and the relative expression levels of PTEN and Akt proteins were increased(P<0.05),while the relative expression level of p-Akt protein was decreased(P<0.05).Compared with the model group, the apoptotic index of neurons in the cerebral ischemic tissues of rats in the electroacupuncture group, magnetic stimulation group and combined group was decreased(P<0.05),and the relative expression levels of PTEN and Akt protein were decreased(P<0.05),while the relative expression level of p-Akt protein was increased(P<0.05).Compared with the electroacupuncture group and magnetic stimulation group, the apoptotic index of neurons in the cerebral ischemic tissues of rats in the combined group was decreased(P<0.05),and the relative expression levels of PTEN and Akt proteins were decreased(P<0.05),while the relative expression level of p-Akt protein was increased(P<0.05).Conclusion Electroacupuncture combined with transcranial magnetic stimulation can improve neurological damage and reduce neuronal apoptosis in cerebral ischemia-reperfusion injury rats.The mechanism may be related to inhibition of the expression of PTEN protein in cerebral ischemia tissues and activation of the PI3 K/Akt signaling pathway.更多还原