亚低温干预下新生大鼠缺氧缺血性脑病时NF-κB基因表达变化及意义

发布时间：2018-07-08 10:12

本文选题：亚低温 + 缺氧缺血性脑损伤　；参考：《山西医科大学》2014年硕士论文

【摘要】：目的利用亚低温干预新生大鼠缺氧缺血性脑损伤（hypoxic-ischemic braindamage, HIBD）动物模型，观察亚低温干预缺氧缺血性脑损伤后脑组织在不同时间点NF-B基因的表达含量，探讨亚低温干预HIBD后NF-B基因表达的变化，为亚低温治疗缺氧缺血性脑病提供理论依据和新的治疗途径。方法7日龄SD大鼠120只，雌雄不限，体重12~18g，随机分为A组（假手术组），B组（常温组），C组（亚低温组），每组根据处死时间不同又分为5个亚组：1h组，6h组，12h组，24h组，48h组各8只，A组乙醚吸入麻醉后切开颈部皮肤，分离但不结扎一侧颈总动脉；B组乙醚吸入麻醉后切开颈部皮肤，分离结扎一侧颈总动脉后置于缺氧仓中（含8%氧气）2h；C组乙醚麻醉后切开颈部皮肤，分离结扎一侧颈总动脉并置于缺氧仓（含8%氧气）2h，并在缺血缺氧后即刻给予亚低温干预。利用RT-PCR技术在mRNA水平检测各组新生大鼠脑组织各组时间点的NF-κB基因含量。结果（1）HIBD后新生大鼠均表现出不同程度行为异常改变。（2）B组不同时间点脑标本，外观形态均表现出不同程度的水肿、萎缩，甚至可出现液化坏死。亚低温组干预缺氧缺血性脑损后不同时间点脑标本的损伤程度较常温组减轻，仅出现轻度水肿。（3）假手术组脑组织中NF-κBmRNA表达量甚微，常温组随着时间的延长，NF-κBmRNA表达逐渐增加，24h达到高峰，，48h后仍高于假手术组，亚低温组各时间点NF-κBmRNA含量均低于常温组（p＜0.01），24h组下降最为显著，亚低温组和常温组各时间点NF-κBmRNA含量与假手术组比较，差异有统计学意义（p＜0.01）。结论（1）亚低温干预的新生大鼠缺氧缺血性脑损伤的脑组织标本损害的病理改变程度减轻，说明亚低温治疗对新生大鼠缺氧缺血性脑损伤的脑组织起到了保护作用。(2)常温组脑组织中，NF-B的含量随着时间的延长逐渐增多，24h达到高峰，48h仍明显高于假手术组，表明NF-B参与缺氧缺血性脑损伤的全过程并起着重要的作用，而在亚低温干预后的脑组织中，NF-B的含量明显降低，24h下降最为显著，此结果表明亚低温的治疗作用可能通过抑制NF-κB的基因表达来起到神经保护的作用。
[Abstract]:Objective to observe the expression of NF-B gene in brain tissue of neonatal rats after mild hypothermia treatment with hypoxic-ischemic brain damage (HIBD) at different time points. To explore the changes of NF-B gene expression after mild hypothermia intervention in HIBD, and to provide a theoretical basis and a new therapeutic approach for mild hypothermia treatment of hypoxic-ischemic encephalopathy. Methods 120 SD rats of 7 days old, male and female, were used. The rats were randomly divided into two groups: group A (sham operation group), group B (normal temperature group) and group C (mild hypothermia group). Each group was divided into 5 subgroups according to the time of death. Each group was divided into 5 subgroups: 1: 1 h group, 12 h group, 24 h group, 48 h group, 8 rats in group A, 8 rats in group A after inhaled anesthesia. One side of common carotid artery was seperated but not ligated. In group B, the neck skin was cut by ether inhalation anesthesia. The common carotid artery was seperated and ligated and placed in anoxic chamber (containing 8% oxygen) for 2 h. The common carotid artery was isolated and ligated and placed in anoxic chamber (containing 8% oxygen) for 2 h and then treated with mild hypothermia immediately after ischemia and hypoxia. The content of NF- 魏 B gene in brain tissue of neonatal rats at different time points was detected by RT-PCR at mRNA level. Results (1) the neonatal rats after HIBD showed different degrees of abnormal behavior. (2) in group B, brain morphology showed edema, atrophy, and even liquefaction and necrosis at different time points. The degree of brain injury in mild hypothermia group was less than that in normothermic group at different time points after hypoxic-ischemic brain injury. (3) the expression of NF- 魏 B mRNA in brain tissue of sham operation group was very small. The expression of NF- 魏 B mRNA in normothermic group was increased gradually with time, and the expression of NF- 魏 B mRNA was still higher than that in sham operation group after 24 hours. The content of NF- 魏 B mRNA in mild hypothermia group was lower than that in normothermic group (p < 0.01). The content of NF- 魏 B mRNA in mild hypothermia group and normal temperature group was significantly higher than that in sham operation group (p < 0.01). Conclusion (1) the pathological changes of brain tissue in neonatal rats treated with mild hypothermia were alleviated after hypoxic-ischemic brain injury. The results showed that mild hypothermia therapy could protect the brain tissue from hypoxic-ischemic brain injury in neonatal rats. (2) the content of NF-B in brain tissue of normothermic group gradually increased with time and reached the peak at 24h and 48h, which was still significantly higher than that in sham operation group. The results indicated that NF-B was involved in the whole process of hypoxic-ischemic brain injury and played an important role, but the content of NF-B in brain tissue decreased significantly after mild hypothermia intervention for 24 hours. These results suggest that mild hypothermia may play a neuroprotective role by inhibiting NF- 魏 B gene expression.
【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R743.31

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