摘要
目的探讨Ras相关C3肉毒素底物1／丝裂素活化蛋白激酶，细胞外信号调节激酶（Rac1／MAPK／ERK）信号通路在大鼠呼吸机相关性肺损伤（VILI）中的作用及其机制。方法将30只SD大鼠按随机数字表法分为自主呼吸组、正常潮气量（VT）组和大VT组，每组10只。自主呼吸组大鼠保留自主呼吸；正常VT组和大VT组大鼠均行气管切开后气管插管，双肺分别给予6mL/kg和40mL／kg VT的机械通气并维持麻醉。通气4h后处死大鼠取心脏血、支气管肺泡灌洗液（BALF）和肺组织。采用酶联免疫吸附试验（ELISA）测定血清和BALF中白细胞介素（IL-1β、IL-6）、肿瘤坏死因子-α（TNF-α）、髓过氧化物酶（MPO）及巨噬细胞炎症因子-2（MIP-2）水平。测定肺组织湿／干重比值（W／D）；苏木素-伊红（HE）染色后，光镜下观察肺组织病理学改变，并进行病理学评分；透射电镜下观察Ⅱ型肺泡上皮细胞（AECⅡ）超微结构改变；采用免疫组化法检测肺组织磷酸化细胞外信号调节激酶（p-ERK）阳性表达，采用免疫荧光技术检测肺组织Rac1和F-肌动蛋白（F-actin）的阳性表达；采用实时荧光定量反转录-聚合酶链反应（RT-qPCR）检测肺组织ERK及Rael的mRNA表达；采用蛋白质免疫印迹试验（Western Blot）检测肺组织Rac1、p-ERK及F-aetin的蛋白表达。结果①与自主呼吸组比较，机械通气两组肺W/D比值均明显升高，以大VT组升高更为显著（6．64±0．88比1．79±0．36，P〈0．01）。②自主呼吸组肺组织及AECⅡ超微结构无明显病理学改变。正常VT组肺组织有轻微水肿及少量炎性细胞浸润；AECⅡ板层小体较少，细胞膜绒毛分布欠均匀。大VT组肺组织明显水肿，肺间隔增宽，肺泡充血，伴有大量炎性细胞浸润，肺泡结构紊乱；AECⅡ形态不规则，核固缩明显，胞质中板层小体数量减少且分布不均。大VT组肺组织病理学评分�
Objective To investigate the role of Ras-related C3 botulinum toxin substrate 1 / mitogen-activated protein kinase/extraeellular signal-regulated kinase （Rac 1/MAPK/ERK） signal pathway in rats with ventilator induced lung injury （VILI） and its mechanism. Methods Thirty Sprague-Dawley （SD） rats were randomly divided into spontaneous respiration group, normal tidal volume （VT） group and high VT group with 10 rats in each group. The rats in spontaneous respiration group were kept their spontaneous breathing. The rats in normal VT group and high VT group were performed tracheal intubation after tracheostomy, and underwent mechanical ventilation on bilateral lungs with 6 mL/kg and 40 mL/kg VT respectively with maintenance anesthesia. After 4-hour ventilation, heart blood, bronchoalveolar lavage fluid （BALF） and lung tissues were harvested. The levels of interleukins （IL-1β, IL-6）, tumor necrosis factor-α （TNF-α）, myeloperoxidase （MPO） and macrophage inflammatory protein-2 （MIP-2） in serum and BALF were determined by enzyme linked immunosorbent assay （ELISA）. Lung wet/dry radio （W/D） was determined. The lung tissues were stained with hematoxylin and eosin （HE）, and pathological changes were observed, and pathological scores were evaluated. The ultra structure changes in type lI alveolar epithelial ceils （AEC Ⅱ） were observed with transmission electron microscope. The positive expressions of phosphorylation of extracellular signal-regulated kinase （p-ERK） were determined by immunohistochemistry, and those of Racl and F-actin were determined by immunofluorescence. The mRNA expressions of ERK and Racl were determined by real-time fluorescent quantitation reverse transcription-polymerase chain reaction （RT-qPCR）, and protein expressions of Rac-1, p-ERK and F-actin were determined by Western Blot. Results ① Compared with spontaneous breathing group, lung W/D in both mechanical ventilation groups was significantly increased, with more significant increase in
作者
陶广华
潘灵辉
荆忍
林飞
戴惠军
葛万运
Tao Guanghua Pan Linghui Jing Ren Lin Fei Dai Huijun Ge Wanyun(Department of Anesthesiology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning 530021, Guangxi, China)
出处
《中华危重病急救医学》
CAS
CSCD
北大核心
2017年第3期249-254,共6页
Chinese Critical Care Medicine
基金
广西自然科学基金重点项目（2014GXNSFDA118026）
广西医疗卫生适宜技术研究与开发项目（S201418-02）
