Objectives: To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi"(LI11) and "Zusanli"(ST36) in the rats with cerebral ischemia reperfusion injury and its influence on programmed necrosis of cerebral cortical neurons.
Methods: Sixty male SD rats were randomly divided into sham-operation group, model group, EA group and inhibitor group, with 15 rats in each group. Left middle cerebral artery occlusion model was established using the modified thread embolism method. In the sham-operation group, the carotid artery was exposed and dissociated in each rat. EA was applied to "Quchi"(LI11) and "Zusanli"(ST36) on the right side for 30 min each time, once daily for 7 days in the rats of the EA group. The rats in the inhibitor group were intraperitoneally injected with norstatin-1 (0.6 mg/kg) for consecutive 7 days. The neurological deficit score of rats in each group was observed. HE staining was adopted to detect the degree of pathological damage of the cerebral cortex in the infarction area. Using TUNEL staining, the apoptosis of cortical neurons in the infarction area was determined；the contents of tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 were detected by ELISA；the mRNA and protein expression of the receptor interacting protein-1 (RIP1), the receptor interacting protein-3 (RIP3) and the substrate mixed lineage kinase like protein (MLKL) were detected by fluorescence quantitative PCR and Western blot, respectively.
Results: In comparison with the sham-operation group, the neurological deficit score in the model group was higher(P<0.01)；HE staining showed that there was the pathological damage in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1β and IL-6, and the mRNA and protein expressions of RIP1, RIP3 and MLKL increased(P<0.01) in the model group. In the EA group, the neurological deficit score was reduced(P<0.01)；HE staining showed that the pathological damage was ameliorated in the infarction area；the neuron apoptosis rate, the contents of TNF-α, IL-1β and IL-6, and the mRNA and protein expressions of RIP1, RIP3, MLKL decreased(P<0.05, P<0.01) when compared with those in the model group.
Conclusions: EA can attenuate cerebral ischemia reperfusion injury and display its neuroprotective effect probably through inhibiting programmed necrosis of cerebral cortical neurons in the rats.
目的: 探讨电针“曲池”“足三里”对脑缺血再灌注损伤大鼠的神经保护作用及对大脑皮层神经元程序性坏死的影响。方法: SD大鼠随机分为假手术组、模型组、电针组、抑制剂组，每组15只。模型组、电针组及抑制剂组大鼠采用改良线栓法制备左侧大脑中动脉阻塞模型；假手术组大鼠仅暴露颈动脉。给予电针组大鼠右侧“曲池”“足三里”电针治疗，30 min/次，1次/d，给予抑制剂组大鼠腹腔注射坏死抑素-1（0.6 mg/kg），均连续干预7 d。观察各组大鼠神经功能缺损评分；HE染色检测梗死区大脑皮层病理损伤程度；TUNEL染色检测梗死区大脑皮层神经元凋亡情况；ELISA法检测梗死区大脑皮层肿瘤坏死因子α（TNF-α）、白细胞介素（IL）-1β、IL-6含量；荧光定量PCR及Western blot法分别检测梗死区大脑皮层受体相互作用蛋白（RIP）1、RIP3、底物混合谱系激酶样蛋白（MLKL）mRNA及蛋白的表达水平。结果: 与假手术组相比，模型组大鼠神经功能缺损评分明显升高（P<0.01）；HE染色显示，梗死区大脑皮层表现出明显脑缺血再灌注病理损伤；梗死区大脑皮层神经元凋亡率，梗死区大脑皮层中TNF-α、IL-1β、IL-6含量，梗死区大脑皮层RIP1、RIP3、MLKL mRNA及蛋白表达水平均明显升高（P<0.01）。与模型组相比，电针组大鼠神经功能缺损评分降低（P<0.01）；HE染色显示，梗死区大脑皮层病理损伤程度明显改善；梗死区大脑皮层神经元凋亡率，梗死区大脑皮层中TNF-α、IL-1β、IL-6含量，梗死区大脑皮层RIP1、RIP3、MLKL mRNA及蛋白表达水平均明显降低（P<0.05，P<0.01）。结论: 电针干预可能通过抑制大鼠大脑皮层神经元程序性坏死，缓解脑缺血再灌注损伤，发挥神经保护作用。.
Keywords: Cerebral ischemia reperfusion injury; Inflammatory reaction; Programmed necrosis; Receptor interacting protein-1/receptor interacting protein-3/substrate mixed lineage kinase like protein pathway.