HSP70在内毒素血症大鼠肺组织的表达及Gln的干预作用

发布时间：2018-06-28 06:04

本文选题：脂多糖 + 热休克蛋白70　；参考：《山西医科大学》2008年硕士论文

【摘要】： 目的本实验旨在观察内毒素血症大鼠不同时间点肺组织热休克蛋白70(HSP70)、丙二醛(MDA)、超氧化物歧化酶(SOD)的变化,以及谷氨酰胺(Gln)对大鼠内毒素血症肺组织损伤的影响,探讨HSP70在内毒素血症大鼠肺组织损伤中的作用以及Gln的干预效应。方法第一部分实验选取健康雌性Wistar大鼠,随机分为两组,对照组(C组),内毒素血症组(E组)。E组于尾静脉注射5mg/kg的内毒素脂多糖(LPS),LPS注射后开始计时,于1h、2h、4h、6h颈动脉放血处死,对照组给予等量的生理盐水,其余同E组。取左肺组织①光镜观察肺组织形态学变化②免疫组织化学方法测定HSP70。取右肺组织用分光光度计法测肺组织MDA含量及SOD活性。在第一部分实验的基础上,第二部分实验选取健康雌性Wistar大鼠随机分为三组:E组,Gln预处理组(G_1组),Gln后处理组(G_2组)。G_1组,G_2组分别在LPS注射前1h和后1h,给予0.75g/kg的Gln,在LPS注射后6h处死大鼠,取左肺组织①光镜观察肺组织形态学变化②免疫组织化学方法测定HSP70,取右肺组织用分光光度计法测肺组织MDA含量及SOD活性,观察Gln的干预效应。结果同对照组相比,E组1h、2h、4h、6h肺组织HSP70表达均增多(P0.05或P0.01),E组2h、4h、6h与1h组相比,肺组织HSP70表达均增多(P0.05或P0.01)且在2h达到峰值; E组1h、2h、4h、6h肺组织MDA含量在均高于对照组(P0.05);E组各时间点肺组织SOD活性均低于对照组(P0.05),4h、6h与1h组相比肺组织SOD活性明显降低(P0.01)。与E组相比,G_1,G_2组肺组织HSP70表达增多(P㩳0.05),SOD活性增高(P㩳0.05),MDA含量明显降低(P㩳0.05);G_1组与G_2组在肺组织HSP70表达,SOD活性,MDA含量等方面比较差异无统计学意义(P㧐0.05)。结论氧自由基参与内毒素性肺损伤的过程,内毒素性肺损伤后的肺组织HSP70表达增多,可能与其参与LPS所致肺损伤后的组织应激保护有关。Gln预处理或后处理都能减轻内毒素血症大鼠肺损伤,作用机制可能与Gln提高机体抗氧化能力以及增加HSP70的表达有关,尚不能认为二者在减轻大鼠LPS所致肺损伤有差别。
[Abstract]:Objective to observe the changes of heat shock protein 70 (HSP70), malondialdehyde (MDA) and superoxide dismutase (SOD) in lung tissue of rats with endotoxemia at different time points and the effect of glutamine (GLN) on lung injury in rats with endotoxemia. To investigate the role of HSP70 in lung tissue injury in rats with endotoxemia and the intervention effect of GLN. Methods in the first part of the experiment, the healthy female Wistar rats were randomly divided into two groups: control group (C group), endotoxemia group (E group). The control group was given the same amount of normal saline, and the others were the same as the E group. The morphological changes of left lung tissue were observed by light microscope. 2. Immunohistochemical method was used to detect HSP70. The content of MDA and the activity of SOD in right lung tissue were measured by spectrophotometer. On the basis of the first part of the experiment, In the second part of the experiment, healthy female Wistar rats were randomly divided into three groups: one hour before injection of 0.75g/kg and one hour after injection, then the rats were killed 6 hours after 0.75g/kg injection, and then the rats were divided into three groups: group G _ (1), group G _ (2), group G _ (1) and group G _ (1), respectively, one hour before and one hour after injection of 0.75g/kg, respectively. The morphologic changes of left lung tissue were observed by light microscope. The content of MDA and the activity of SOD in right lung tissue were measured by immunohistochemical method, and the intervention effect of GLN was observed. Results compared with the control group, the expression of HSP70 in the lung tissue of the E group was significantly higher than that of the control group (P0.05 or P0.01), and the expression of HSP70 in the lung tissue of the E group was significantly higher than that of the control group (P0.05 or P0.01). The expression of HSP70 in lung tissue increased (P0.05 or P0.01) and reached the peak at 2h, and the MDA content of lung tissue in group E was significantly higher than that in control group (P0.05) at 1h, 2h, 4h and 6h (P0.05). The SOD activity in group E was significantly lower than that in control group (P0.05) at 4h and 6h (P0.01). Compared with group E, the expression of HSP70 in lung tissue increased (P0. 05) and SOD activity increased (P0. 05). MDA content decreased significantly in group G1 and group 2. There was no significant difference between group 1 and group 2 in the expression of SOD activity and MDA in lung tissue (P0. 05). Conclusion oxygen free radicals are involved in the process of endotoxin induced lung injury, and the expression of HSP70 in lung tissue after endotoxin induced lung injury is increased. It may be related to the involvement of GLN in the tissue stress protection after LPS induced lung injury. GLN pretreatment or post-treatment can reduce the lung injury in rats with endotoxemia, and the mechanism may be related to the increase of GLN's antioxidant ability and the expression of HSP70. It can not be concluded that there is a difference between the two groups in reducing the lung injury induced by LPS in rats.
【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R363

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