甲基强的松龙对脂多糖诱导的大鼠急性肺损伤高迁移率蛋白1表达的影响

发布时间：2018-06-05 23:57

本文选题：脂多糖 + 急性肺损伤　；参考：《中南大学》2013年硕士论文

【摘要】：目的：通过检测脂多糖诱导的急性肺损伤(ALI)大鼠肺组织中高迁移率蛋白1(HMGB1) mRNA及其蛋白表达水平,以及甲基强的松龙注射剂干预后对急性肺损伤大鼠肺组织HMGB1表达的影响,探讨HMGB1在脂多糖诱导的急性肺损伤中的作用,以及甲基强的松龙注射剂干预后在急性肺损伤中的表达变化。方法：清洁级雄性SD大鼠54只,随机分成3组,每组18只；(1)正常对照组(N组)：每只尾静脉注射生理盐水2ml/kg,1小时后再尾静脉注射生理盐水1ml/kg;(2)急性肺损伤组(ALI组)：尾静脉注射脂多糖6mg/kg,1小时后再尾静脉注射生理盐水1ml/kg;(3)甲基强的松龙干预组(MPN组)：每只尾静脉注射脂多糖6mg/kg,1小时后再尾静脉注射甲基强的松龙20mg/kg。观察各组大鼠行为改变,三组分别于注射后12h、24h、36h采集标本,每个时相点6只大鼠。采集动脉血气,放血后取部分肺组织行HE染色,观察肺组织病理学改变,并测定干湿比重(W/D)；采用免疫组织化学法和Real-Time PCR法检测大鼠肺组织HMGB1表达水平。结果：(1)各组一般状况的变化：ALI组大鼠12h后出现毛发竖直,蜷作一团,呼吸急促,爪趾发绀,反应迟钝,萎靡厌食,排便减少或性状改变,24h最明显,36h症状有所减轻；MPN组症状轻于同时点ALI组。 (2)各组干湿比重的变化：ALI组大鼠肺干湿比重(W/D)明显增加,各时相点与N组比较差异均有显著统计学意义(P0.01),但各时相点之间无统计学差异(P0.05), MPN组肺干湿比重(W/D)增高,与N组比较有统计学意义(P0.01), MPN组与ALI组比较肺干湿比重(W/D)下降。 (3)各组血气变化：N组P02正常,ALI组大鼠血气分析P02明显下降(P0.05), MPN组PO2下降,同一时相点较ALI组减轻。 (4)各组肺组织病理改变：N组大鼠肺组织小叶结构清晰,肺泡腔及肺泡间质无炎性细胞浸润。ALI组肺组织呈不同程度肿胀,表面散在紫红色淤血斑,肺泡壁间隔增宽,肺泡及肺血管明显充血水肿,肺泡腔内见红细胞及炎性细胞渗出,肺间质也见大量炎症细胞浸润,且随着时间的延长,肺组织病理改变逐渐加重,24h最明显,36h有所减轻。MPN组较同一时相点ALI组肺组织改变有不同程度的减轻。 (5)各组肺组织中HMGB1表达变化：正常组中大鼠肺组织有少量HMGB1mRNA及其蛋白表达,ALI组和MPN组大鼠肺组织中HMGB1mRNA及其蛋白表达水平明显高于N组(均p0.05),且随着时间延长呈逐渐增加趋势,24h HMGB1mRNA表达达峰值；同一时相点ALI组大鼠肺组织HMGB1mRNA及其蛋白表达水平高于MPN组(P0.05)。结论： 1、急性肺损伤中肺组织HMGB1mRNA及其蛋白表达明显升高,且24h时达高峰,36h下降但仍高于N组,提示HMGB1在炎症后期持续性高水平表达,在ALI发生、发展过程中尤其是ALI后期失控性炎症反应过程中可能发挥重要作用。 2、甲基强的松龙注射剂干预后急性肺损伤中肺组织：HMGB1mRNA及其蛋白表达较急性肺损伤组有所降低,可有效改善大鼠急性肺损伤的炎症反应,对脂多糖所致的急性肺损伤有一定的保护作用。
[Abstract]:Objective: to detect the expression of high mobility protein 1 (HMGB1) mRNA and protein in lung tissue of rats with acute lung injury (ALI) induced by lipopolysaccharide, and the effect of methylprednisolone injection on the expression of HMGB1 in lung tissue of rats with acute lung injury, and explore the role of HMGB1 in the acute lung injury induced by lipopolysaccharide, as well as the effect of HMGB1 on the acute lung injury induced by lipopolysaccharide. The expression of basal prednisolone injection in acute lung injury.
Methods: 54 clean male SD rats were randomly divided into 3 groups, 18 rats in each group, and (1) normal control group (group N): each caudal vein was injected with saline 2ml/kg, and 1ml/kg was injected into the tail vein after 1 hours; (2) the acute lung injury group (ALI group): the tail vein was injected with lipopolysaccharide 6mg/kg, and the tail vein was injected with saline 1ml/kg after 1 hours; (3) a The MPN group (group MPN): each tail vein was injected with lipopolysaccharide 6mg/kg, and after 1 hours the tail vein was injected with methylprednisolone 20mg/kg. to observe the behavior changes in each group. The three groups were collected respectively after the injection of 12h, 24h, 36h and 6 rats at each time phase. The blood gas was collected and the lung tissue was stained with HE after blood letting and the lung was observed. The changes of histopathology and dry wet weight (W/D) were measured. The expression level of HMGB1 in lung tissue was detected by immunohistochemistry and Real-Time PCR.
Results: (1) the changes in the general condition of each group: the rats in group ALI had hair vertical, curled up, breathing quickly, cyanosis of claw toes, slow reaction, weary anorexia, reduced defecation or change of character, 24h was most obvious, 36h symptoms were lightened, and MPN group was less than group ALI in MPN.
(2) the change of dry and wet specific gravity of each group: the lung dry and wet specific gravity (W/D) of the ALI group increased significantly, and the difference of the phase points with the N group had significant statistical significance (P0.01), but there was no statistical difference between the phase points (P0.05), and the proportion of lung and humidity (W/D) in the MPN group increased, and was statistically significant (P0.01), and the lung dry and wet ratio was compared with the ALI group. The MPN and ALI groups compared the lung dry wet ratio. The weight (W/D) drops.
(3) blood gas changes in each group: P02 in group N was normal, blood gas analysis P02 in group ALI decreased significantly (P0.05), PO2 in MPN group decreased, and the same time point decreased compared with ALI group.
(4) pathological changes of lung tissue in each group: the structure of pulmonary lobule in group N was clear, pulmonary alveolus and alveolar interstitial free cell infiltration in group.ALI, the lung tissue was swollen in varying degrees, the surface scattered in the purple red congestion spot, the alveolar septum widened, the alveolar and pulmonary blood vessels were obviously congested and edema, the alveolar and inflammatory cells exuded and the pulmonary interstitium was found. There was also a large number of inflammatory cells infiltrating, and with the prolongation of time, the pathological changes of lung tissue were gradually aggravated, 24h was the most obvious, and 36h was relieved in.MPN group as compared with the same phase point ALI group.
(5) the change of HMGB1 expression in lung tissue of each group: there was a small amount of HMGB1mRNA and protein expression in the lung tissue of the normal group. The expression level of HMGB1mRNA and protein in lung tissue of group ALI and MPN rats was significantly higher than that of group N (P0.05), and the expression of 24h HMGB1mRNA expression was gradually increasing with time, and the same phase point ALI group rats were in the same time. The expression level of HMGB1mRNA and protein in lung tissue was higher than that in group MPN (P0.05).
Conclusion:
1, the expression of HMGB1mRNA and its protein in lung tissue in acute lung injury increased significantly, and reached the peak at 24h, but 36h decreased but still higher than that in group N, suggesting that HMGB1 may be expressed at a high level in the late stage of inflammation, which may play an important role in the process of ALI, especially in the process of uncontrolled inflammatory reaction in the late stage of ALI.
2, after the methylprednisolone injection, the expression of HMGB1mRNA and its protein expression in acute lung injury is lower than that in the acute lung injury group. It can effectively improve the inflammatory response of acute lung injury in rats and protect the acute lung injury caused by lipopolysaccharide.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R563.8

【参考文献】