内质网应激在早产鼠高氧肺损伤中的作用

发布时间：2018-04-20 07:20

本文选题：高浓度氧 + 肺损伤　；参考：《泸州医学院》2013年硕士论文

【摘要】：目的研究内质网应激在高氧诱导早产鼠肺损伤中的作用。方法将新生早产Wistar鼠48只在生后12小时随机分为对照组、高氧组，其体质量无统计学意义，对照组置于21%氧浓度空气中，高氧组则吸入95%的高分子体积氧建立高氧肺损伤模型，两者其他条件相同。两组小鼠在上述相应处理后1d、3d、7d分批以断颈放血的方式处死，每组取动物8只，然后取肺组织。以左肺制作石蜡切片，采用苏木精一伊红（HE）染色观察肺组织病理改变；免疫组织化学链霉菌抗生物素蛋白-过氧化物酶连结(streptavidin-peroxidase,SP）法检测内质网应激相关指标：ERp57; c/EBP同源蛋白（CHOP）在各组肺组织内的表达；采用原位末端标记法（TUNEL）检测肺细胞凋亡情况。结果(1)肺组织病理学改变：光镜下观察对照组大鼠肺组织结构正常。高氧组暴露1d肺组织病理学检查无明显差异，均为大而不规则的肺泡腔。高氧组暴露3d，可见小血管扩张，肺泡上皮肿胀，肺泡腔及间质内有大量红细胞和炎细胞渗出；暴露7d上述变化更明显，(2) ERp57; c/EBP同源蛋白（CHOP）在肺组织的表达与分布：ERp57在肺组织中普遍表达于肺泡上皮细胞、血管内皮细胞、支气管上皮细胞的细胞质中。对照组ERp57表达很少，高氧组ERp57随着高氧暴露时间的延长表达逐渐增多，与对照组相比有统计学差异。（平均光密度值AOD:对照组1d0.235±0.023、3d0.257±0.056、7d0.267±0.058；高氧组1d0.320±0.02、3d0.347±0.054、7d0.400±0.0273d、7d P＜0.05）; c/EBP同源蛋白（CHOP）在肺组织中也普遍表达于肺泡上皮细胞、血管内皮细胞、支气管上皮细胞的细胞质中。对照组c/EBP同源蛋白（CHOP）表达微弱，高氧组c/EBP同源蛋白（CHOP）随着暴露时间的延长表达逐渐明显，与对照组相比有统计学差异。（平均光密度值AOD:对照组1d0.165±0.037、3d0.268±0.036、7d0.207±0.034；高氧组1d0.307±0.048、3d0.318±0.06、7d0.330±0.0541d、3d、7d P＜0.05）；(3) TUNEL检测凋亡细胞：对照组也可见少许TUNEL阳性细胞，高氧组则随着高氧暴露时间的延长TUNEL阳性细胞明显增多，与对照组相比有明显统计学差异。(凋亡指数Apoptotic index, AI：对照组1d14.44±1.10、3d14.60±2.06、7d14.35±1.45；高氧组1d25.49±1.25、3d44.97±1.82、7d55.34±1.761d、3d、7d P＜0.01);(4) ERp57、c/EBP同源蛋白表达与细胞凋亡指数相关性：采用直线相关分析结果如下：细胞凋亡指数和ERP57AOD比较，r=0.789，P0.01；与c/EBP同源蛋白比较r=0.645，P0.01,均提示呈显著正相关。结论1.高氧暴露可导致早产鼠肺组织产生急性肺损伤病理性改变。而这一表现随着高氧暴露时间延长显示更明显。 2.高氧暴露可致新生大鼠肺组织ERp57; c/EBP同源蛋白表达增加,提示内质网应激细胞凋亡参与了高氧肺损伤，并发挥重要作用，具体机制仍需要进一步研究。 3. ERp57; c/EBP同源蛋白表达与细胞凋亡指数动态变化具有相关性。
[Abstract]:Objective to study the role of endoplasmic reticulum stress in hyperoxia-induced lung injury in preterm rats. Methods 48 preterm Wistar rats were randomly divided into control group (n = 48) and hyperoxia group (n = 48). The control group was placed in air with 21% oxygen concentration and the hyperoxia group inhaled 95% high molecular weight oxygen to establish hyperoxia-induced lung injury model. The other two conditions are the same. The mice of the two groups were killed in batches at 1 day, 3 days and 7 days after the corresponding treatment, and 8 animals were taken from each group, and then lung tissue was taken out. Paraffin sections were made from the left lung, and the pathological changes of lung tissue were observed by hematoxylin-eosin (HEH) staining. Immunohistochemical streptavidin-peroxidase (SPP) method was used to detect the expression of c/EBP homologue protein (CHOP) and endoplasmic reticulum stress (ERp57) in lung tissues, and Tunel was used to detect the apoptosis of lung cells. Results 1) pathological changes of lung tissue: the lung tissue structure of the control group was normal under light microscope. There was no significant difference in histopathological examination of lung in hyperoxia group after 1 day exposure, all of them were large and irregular alveolar lumen. In hyperoxia group, small vessels dilated, alveolar epithelium swelling, erythrocytes and inflammatory cells exudated in alveolar cavity and interstitium. The expression and distribution of c/EBP homologue protein (CHOP5) in lung tissues were found in alveolar epithelial cells, vascular endothelial cells and bronchial epithelial cells, and the expression and distribution of c/EBP homologous protein CHOP57 in lung tissue were also found in the cytoplasm of alveolar epithelial cells, vascular endothelial cells and bronchial epithelial cells. The expression of ERp57 in hyperoxia group increased with the prolongation of hyperoxia exposure time, and there was statistical difference between hyperoxia group and control group. (average optical density value: 1d0.235 卤0.023 卤0.056 days 0.257 卤0.056 days 0.267 卤0.058; 1d0.320 卤0.02 卤0.054 d 0.347 卤0.054 d 0.347 卤0.027 3 d 7d P < 0.05; c/EBP homologous protein Chopp also expressed in alveolar epithelial cells, vascular endothelial cells, bronchial epithelial cells) in lung tissue. The expression of c/EBP homologue protein in control group was weak, and the expression of c/EBP homologue protein in hyperoxia group was gradually obvious with the prolongation of exposure time, and there was significant difference between the control group and the control group. (mean optical density: 1d0.165 卤0.037 卤0.036 卤0.268 卤0.036 卤0.207 卤0.034 on day 0.207 卤0.034; 1d0.307 卤0.048 卤0.06 卤0.318 卤0.06 on 7d 0.330 卤0.0541d / 3 d / d P < 0.05D / d P < 0.05D / d) apoptotic cells were detected by TUNEL. A few TUNEL positive cells were also found in the control group, while in the hyperoxia group, the number of TUNEL positive cells increased significantly with the prolongation of the hyperoxia exposure time (P < 0.05), and the number of TUNEL positive cells in the hyperoxia group was significantly higher than that in the hyperoxia group (P < 0.05). Compared with the control group, there was significant statistical difference. (Apoptotic index, AI: control 1d14.44 卤1.10d14.60 卤2.06d14.35 卤1.45d; hyperoxia group 1d25.49 卤1.252d44.97 卤1.82d54.97 卤1.82d7d 55.34 卤1.761dcEBP protein expression and apoptosis index P < 0.01p57cP / EBP homologous protein expression and apoptosis index: the results of linear correlation analysis were as follows: apoptotic index and ERP57AOD were 0.789P0.01; compared with c/EBP homologous protein ru 0.645P0.01; P < 0.01; P < 0.01); the expression of ERp57cEBP homologous protein was compared with c/EBP homologue protein. The results of linear correlation analysis were as follows: the apoptosis index and ERP57AOD were 0.789P0.01and 0.645P0.01respectively. There was a significant positive correlation. Conclusion 1. Hyperoxia exposure may lead to pathological changes of acute lung injury in preterm rats. This performance was more obvious with the time of hyperoxia exposure. 2. The expression of ERp57; c/EBP homologous protein in lung tissue of neonatal rats was increased after hyperoxia exposure, suggesting that endoplasmic reticulum stress cells apoptosis was involved in hyperoxia lung injury and played an important role. The specific mechanism still needs to be further studied. 3. ERp57; c/EBP homologous protein expression was correlated with the dynamic change of apoptosis index.
【学位授予单位】：泸州医学院
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R722.6

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