不同波形电针预处理对大鼠脓毒症脑损伤的影响

Effect of electroacupuncture pretreatment with different waveforms on septic brain injury in rats

目的观察不同波形电针预处理对大鼠脓毒症脑损伤的影响。方法成年雄性SD大鼠80只,3月龄,体重200~220g,随机分为五组:假手术组(Sham组)、盲肠结扎穿孔组(CLP组)、连续波组(CW组)、疏密波组(DW组)及间断波组(IW组),每组16只。采用盲肠结扎穿孔(CLP)术制备脓毒症模型。观察大鼠脑水肿、额叶皮质病理结构(HE染色)、凋亡(TUNEL染色)及TLR4表达变化(免疫组织化学染色);测定血清、额叶皮质肿瘤坏死因子(TNF)-α、白细胞介素(IL)-6、丙二醛(MDA)浓度和超氧化物歧化酶(SOD)活性。结果与Sham组比较,CLP组、CW组、DW组及IW组出现脑水肿、脑损伤及神经元凋亡明显加重(P<0.05);血清及额叶皮质TNF-α、IL-6及MDA浓度明显升高,SOD活性明显降低(P<0.05);TLR4表达明显增加(P<0.05)。与CLP组比较,CW组、DW组及IW组脑水肿、脑损伤及神经元凋亡明显减轻(P<0.05);血清及额叶皮质TNF-α、IL-6及MDA浓度明显下降,SOD活性明显升高(P<0.05);TLR4表达量明显降低(P<0.05)。电针组之间比较,DW组改善作用最明显,IW组次之,CW组较差(P<0.05)。结论不同波形电针能减轻大鼠脓毒症脑损伤且疏密波最佳,可能与抑制炎症、氧化应激及神经元凋亡有关。

Objective To observe the effects of three pretreatments of electroacupuncture with different waveforms for septic brain injury in rats,and to explore the optimal waveform.Methods Eighty male Sprague-Dawley rats were divided randomly into five groups（n=16）：sham group,cecal ligation and puncture group（group CLP）,continuous wave group（group CW）,dilatational wave group（group DW）and intermittent wave group（group IW）.A rat sepsis model was prepared by cecal ligation and puncture.Brain water content was detected.Tumor necrosis factor（TNF）-α,interleukin（IL）-6,malondialdehyde（MDA）and superoxide dismutase（SOD）in serum and frontal cortex were detected 48 h after sham or CLP operation.Pathological changes of frontal cortex,expression of Toll-like receptor-4（TLR4）,and apoptosis of nerve cells were observed by hematoxylin and eosin staining（HE）,immunohistochemistry and TUNEL assay,respectively.Results Compared with the sham group,encephaledema,as well as brain injury and neuron apoptosis increased in group CLP（P〈0.05）.Concentrations of tumor necrosis factor-α,interleukin-6,and malondialdehyde in serum and frontal cortex significantly increased,and the activities of superoxide dismutase significantly decreased（P〈0.05）.The expression of TLR4 significantly increased（P〈 0.05）.Compared with group CLP,the aforementioned indicators in the continuous,dilatational,and intermittent wave groups significantly improved（P 〈0.05）.Compared among the electroacupunctured groups,the effect of dilatational wave was the most significant,followed by intermittent wave,and continuous wave was the least one（P〈0.05）.Conclusion EA pretreatment with different waveforms at Baihui and Tsusanli acupoints could reduce the septic brain injury,and DW might be the best one.The mechanism might be related with the inhibition of inflammation and oxidative stress response and the decrease in nerve cell apoptosis.