锌对脊髓缺血再灌注损伤大鼠的保护作用及其机制的研究

发布时间：2018-03-15 11:28

本文选题：锌　切入点：脊髓缺血再灌注损伤　出处：《吉林大学》2015年硕士论文　论文类型：学位论文

【摘要】：脊髓缺血再灌注损伤（SCII）是指在脊柱外科和胸腹主动脉等手术过程中导致脊髓缺血引起脊髓的损伤，是胸腹主动脉手术和脊柱外科的严重并发症之一。目前针对脊髓缺血再灌注损伤的治疗方法虽有一定的作用，但疗效并不显著。因此，如何减轻或避免脊髓缺血再灌注损伤成为人们关注和亟待解决的重点。相关研究表明，锌是机体的必需微量元素，是机体多种酶的必要成分或活化因子。参与多种信号通路的转导，具有抗炎症抗氧化和抗纤维化等作用。本研究首先对大鼠进行外源性锌离子补充，然后制备大鼠SCII动物模型，观察其发生SCII的情况，进而探讨锌离子对脊髓缺血再灌注损伤的保护性作用并初步探讨其作用机制。目的探讨外源性补锌对脊髓缺血再灌注损伤大鼠的保护作用，并且初步探讨其作用机制。方法60只Wistar大鼠随机分为5组，每组12只，雌雄各半，分别为假手术组、模型组、硫酸锌预处理高剂量组（100mg/kg/d）、中剂量组（50mg/kg/d）和低剂量组（25mg/kg/d）。各剂量组每日灌胃给予硫酸锌1次，连续7天。假手术组和模型组给予相同体积生理盐水，，7天后制备脊髓缺血再灌注损伤动物模型，损伤后48h采用Tarlov评分对脊髓缺血再灌注损伤模型进行后肢神经功能评价；HE染色进行病理组织学观察；测定脊髓组织中ATP酶、MAO活性和T-AOC含量。免疫组化方法测定自噬的标志物Beclin1在脊髓组织中的表达。结果与模型组比较，各给锌组大鼠神经功能评分明显高于模型组，差异具有显著性（P 0.05）。病理组织观察发现，脊髓缺血再灌注组部分神经元受损，硫酸锌处理组细胞形态均有一定改善。Beclin1免疫组织化学染色显示，各干预组中，25mg/kg/d组和50mg/kg/d组Beclin1蛋白表达显著高于假手术组（P 0.05），各干预组Beclin1蛋白表达与模型组相比均有显著性降低（P 0.05）。各硫酸锌处理组Na+-K+-ATP酶活性明显低于假手术组（P＜0.05），但明显高于模型组（P＜0.05）。模型组和各硫酸锌处理组脊髓组织Ca2+-Mg2+-ATP酶活性显著低于假手术组（P＜0.05）。模型组和各硫酸锌处理组大鼠脊髓组织内的MAO活性均显著高于假手术组（P＜0.05），且100mg/kg/d硫酸锌处理组MAO活性显著低于模型组（P＜0.05）。模型组和各硫酸锌处理组大鼠脊髓组织内的T-AOC含量显著低于假手术组（P＜0.05）。模型组大鼠脊髓组织中T-AOC含量最低，随着硫酸锌剂量的增加，T-AOC含量呈上升趋势。结论补充锌离子可提高大鼠神经功能评分，增强其抗氧化应激能力，减少病理组织损伤，对脊髓缺血再灌注损伤起到一定保护作用。
[Abstract]:Spinal cord ischemia-reperfusion injury (SCII) refers to spinal cord injury caused by spinal cord ischemia during spinal surgery and thoracoabdominal aorta surgery. It is one of the serious complications of thoracoabdominal aortic surgery and spinal surgery. Although the current treatment of spinal cord ischemia-reperfusion injury has a certain effect, but the effect is not significant. How to reduce or avoid spinal cord ischemia-reperfusion injury has become the focus of attention and urgent need to be solved. Related studies have shown that zinc is an essential trace element in the body. It is an essential component or activator of many enzymes in the body. It is involved in the transduction of many signaling pathways, and has anti-inflammatory, anti-oxidation and anti-fibrosis effects. In this study, we first supplemented the rats with exogenous zinc ions, and then made the rat SCII animal model. To investigate the protective effect of zinc ion on spinal cord ischemia-reperfusion injury and its mechanism. Objective to investigate the protective effect of exogenous zinc supplementation on spinal cord ischemia reperfusion injury in rats and its mechanism. Methods Sixty Wistar rats were randomly divided into 5 groups, 12 rats in each group, half male and half female. They were sham-operated group, model group, high dose zinc sulfate preconditioning group (100 mg / kg / d), middle dose group (50 mg / kg / d) and low dose group (25 mg / kg / d). The spinal cord ischemia-reperfusion injury model was established 7 days after sham-operation group and model group were given the same volume of normal saline for 7 days. 48 hours after injury, the spinal cord ischemia-reperfusion injury model was evaluated by Tarlov score and HE staining was used to observe the histopathology. The activity of ATP enzyme Mao and the content of T-AOC in spinal cord tissue were measured. The expression of Beclin1, a marker of autophagy, was detected by immunohistochemistry. Results compared with the model group, the neurological function scores of each zinc group were significantly higher than those of the model group, and the difference was significant (P 0.05). The pathological observation showed that some neurons were damaged in the spinal cord ischemia-reperfusion group. In zinc sulfate treated group, the cell morphology was improved. Beclin1 immunohistochemical staining showed that, The expression of Beclin1 protein in 25 mg / kg / d group and 50 mg / kg / d group was significantly higher than that in sham operation group (P 0.05). The expression of Beclin1 protein in each intervention group was significantly lower than that in model group (P 0.05). The Na K ATPase activity in each zinc sulfate treatment group was significantly lower than that in sham operation group. The activity of Ca2 mg 2 ATPase in spinal cord in model group and zinc sulfate treatment group was significantly lower than that in sham operation group (P < 0 05). The MAO activity in spinal cord tissue of model group and zinc sulfate treatment group was significantly higher than that of sham operation group. The activity of MAO in the 100 mg / kg / d zinc sulfate treatment group was significantly lower than that in the model group (P < 0.05). The T-AOC content in the spinal cord of the model group and the zinc sulfate treatment group was significantly lower than that in the sham operation group (P < 0.05). The content of T-AOC in the spinal cord of the model group was the lowest. The content of T-AOC increased with the increase of zinc sulfate dosage. Conclusion supplementation of zinc ion can improve the neurological function score, enhance the ability of antioxidant stress, reduce the injury of pathological tissue and protect the spinal cord from ischemia-reperfusion injury.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R651.2

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