高迁移率族蛋白B1 / Toll样受体4信号通路在脓毒症大鼠致急性肺损伤中的作用研究

目的探讨高迁移率族蛋白B1（HMGB1） / Toll样受体4（TLR4）信号通路对脓毒症导致的急性肺损伤大鼠的影响。 方法将60只清洁级雄性Sprague Dawley大鼠分为假手术组、脓毒症组和实验组,每组各20只。假手术组大鼠麻醉后开腹翻动肠道,随即关腹;脓毒症组和实验组行盲肠结扎穿孔（CLP）术后0.5 h于尾静脉分别注射等渗NaCl溶液（4 mL / kg）及抗HMGB1单克隆抗体（2 mg / kg）。各组分别取10只用于观察大鼠CLP建模后7 d存活情况,其余大鼠于造模后24 h处死并留取肺组织标本。计算各组大鼠的肺损伤Smith评分,并比较各组大鼠HMGB1和TLR4阳性蛋白在肺组织中的表达水平。采用酶联免疫吸附测定检测各组大鼠肺泡灌洗液（BALF）中肿瘤坏死因子α（TNF-α）、白细胞介素6（IL-6）、HMGB1和TLR4水平,计算每个巨噬细胞内微球蛋白数以比较各组大鼠肺泡巨噬细胞（AM）的吞噬功能,并采用Western-blotting法测定AM内HMGB1、TLR4蛋白表达水平。 结果假手术组大鼠建模后7 d全部存活,脓毒症组大鼠仅3只存活,实验组大鼠5只存活。各组大鼠间存活情况的比较,差异有统计学意义（ χ² = 10.833,P = 0.004）;且假手术组大鼠的存活情况明显优于脓毒症组与实验组大鼠（P均< 0.017）,而脓毒症组与实验组大鼠间存活情况比较,差异无统计学意义（P = 0.120）。假手术组、脓毒症组及实验组大鼠间肺组织损伤评分[（2.20 ± 0.27）、（8.20 ± 1.27）、（4.25 ± 2.21）分,F = 56.432,P < 0.001],肺组织HMGB1阳性蛋白[（10.4 ± 1.5）、（34.4 ± 5.0）、（26.6 ± 6.9）,F = 35.203,P = 0.003]、TLR4阳性蛋白[（10.6 ± 2.1）、（48.0 ± 5.8）、（38.2 ± 5.3）,F = 103.414,P = 0.002],BALF中TNF-α[（19 ± 4）、（45 ± 4）、（35 ± 4）μg / L,F = 2.749,P < 0.001]、IL-6[（56 ± 19）、（86 ± 15）、（70 ± 19）μg / L,F = 4.648,P = 0.001]、HMGB1[（41 ± 18）、（70 ± 15）、（56 ± 12）μg / L,F = 7.254,P = 0.002]、TLR4[（20.9 ± 1.8）、（51.2 ± 1.6）、（49.8 ± 2.6）μg / L,F = 3.978,P = 0.035],AM的吞噬功能[（21.8 ± 2.7）、（3.1 ± 1.9）、（12.6 ± 2.2）个,F = 32.821,P = 0.001]及AM中HMGB1蛋白[（11 ± 3）、（40 ± 15）、（24 ± 13）,F = 7.253,P < 0.001]、TLR4蛋白[（0.9 ± 0.4）、（1.2 ± 0.6）、（1.1 ± 0.4）,F = 3.984,P = 0.028]的比较,差异均有统计学意义。进一步两两比较发现,脓毒症组与实验组大鼠肺组织损伤评分,肺组织HMGB1阳性蛋白、TLR阳性蛋白表达水平,BALF中TNF-α、IL-6、HMGB1水平及AM中HMGB1蛋白表达水平均明显高于假手术组大鼠,且脓毒症组大鼠更高（P均< 0.05）;脓毒症组及实验组大鼠AM的吞噬功能均显著低于假手术组,且脓毒症组更低（P均< 0.05）;脓毒症组及实验组大鼠BALF中TLR4水平及AM中TLR4蛋白表达水平均显著高于假手术组（P均< 0.05）,但脓毒症组与实验组间上述指标的比较,差异均无统计学意义（P均> 0.05）。 结论通过抑制HMGB1 / TLR4信号通路可以缓解脓毒症致肺损伤大鼠肺组织的炎症损伤,抑制炎症介质过度释放,并增强AM的细胞吞噬功能。     

光甘草定调控NETs抑制细胞焦亡缓解脓毒症肺损伤机制

目的探讨传统中药光甘草定对脓毒症肺损伤中性粒细胞胞外诱捕网(neutrophil extracellular traps, NETs)形成及细胞焦亡影响。方法将24只雄性Wistar大鼠, 按照随机数字表法分为3组:脓毒症组采用盲肠结扎穿孔术(cecalligation and puncture, CLP)建立脓毒症大鼠模型;光甘草定组(CLP+GLA)行CLP及光甘草定灌胃(30 mg/kg);假手术组(Sham)行盲肠探查术, 仅进行盲肠翻动后关腹。12 h后留取血浆、肺泡灌洗液及肺组织标本检测。测定肺泡灌洗液蛋白含量;测定肺组织湿重/干重(W/D)比值;用苏木精-伊红(HE)染色后观察肺组织病理学改变;用酶联免疫吸附实验(ELISA)检测血浆中NETs标志物MPO-DNA复合物水平、焦亡相关炎症因子IL-18、IL-1β的表达水平;Western blot技术检测大鼠肺组织Caspase-1及Cleaved-caspase-1焦亡蛋白的变化。结果脓毒症组肺泡灌洗液总蛋白浓度较假手术组明显升高(P<0. 01), 光甘草定组肺泡灌洗液总蛋白浓度较脓毒症组下降(P<0. ...     

瑞芬太尼对脓毒症诱导急性呼吸窘迫综合征大鼠的保护作用研究

目的观察瑞芬太尼对脓毒症诱导产生急性呼吸窘迫综合征（ARDS）大鼠的保护作用及机制。 方法将40只SD大鼠分为对照组、ARDS组、瑞芬太尼对照组及瑞芬太尼治疗组,每组各10只。ARDS组与瑞芬太尼治疗组大鼠经股静脉注射7.5 mg/kg脂多糖以制备ARDS大鼠模型,对照组与瑞芬太尼对照组大鼠予以等体积生理盐水;而后瑞芬太尼对照组及治疗组在注射6 h后给予静脉注射瑞芬太尼0.04 μg/kg,ARDS组予以等体积生理盐水。所有大鼠于脂多糖注射后8 h处死。取右肺予以病理学检测,取左肺上叶进行髓过氧化物酶（MPO）水平、肺湿/干重（W/D）及肿瘤坏死因子α（TNF-α）,白细胞介素1β（IL-1β）和IL-6水平的比较,并对支气管肺泡灌洗液（BALF）中蛋白含量及细胞计数进行检测。 结果静脉注射脂多糖8 h后,肺组织病理切片提示肺内大量炎性细胞浸润,而给予瑞芬太尼处理的动物上述病理学改变明显减轻。ARDS组大鼠MPO水平[（1.98 ± 0.14）U/g vs.（0.89 ± 0.12）U/g]、肺W/D比值[（8.51 ± 0.13）vs.（3.83 ± 0.08）]、TNF-α[（1 141 ± 114）ng/L vs.（186 ± 8）ng/L]、IL-1β[（1 866 ± 291）ng/L vs.（201 ± 30）ng/L]、IL-6[（528 ± 61）ng/L vs.（246 ± 35）ng/L]、BALF中蛋白含量[（0.96 ± 0.02）g/L vs.（0.29 ± 0.01）g/L]及细胞计数[（11.57 ± 1.04）×10⁸/ml vs.（1.39 ± 0.29）× 10⁸/ml]均明显高于对照组（P均<0.05）,而瑞芬太尼治疗组大鼠MPO水平为（1.01 ± 0.12）U/g,肺W/D比值4.05 ± 0.12,TNF-α为（573.8 ± 49.6）ng/L,IL-1β为（769.5 ± 49.8）ng/L,IL-6为（365.5 ± 35.8）ng/L,BALF中蛋白含量（0.53 ± 0.02）g/L,细胞计数为（7.57 ± 0.66）× 10⁸/ml,上述指标均明显低于ARDS组（P均<0.05）。 结论瑞芬太尼对脓毒症诱导的ARDS大鼠具有保护作用。     

萝卜硫素对脓毒症急性肺损伤大鼠肺组织Toll样受体4/核因子κB信号通路的影响

目的评价萝卜硫素对于脓毒症急性肺损伤（ALI）大鼠肺组织炎症反应以及Toll样受体4（TLR4）/核因子κB（NF-κB）信号通路的影响。 方法将30只雄性Sprague Dawley大鼠按随机数字表法分成假手术组、模型组和治疗组,每组各10只。模型组和治疗组大鼠采用盲肠结扎穿孔（CLP）法制备大鼠脓毒症模型,治疗组大鼠在术后立即腹腔注射50 mg/kg的萝卜硫素注射液,其余两组注入等量等渗NaCl溶液;于术后24 h大鼠右侧颈总动脉采集动脉血标本,然后处死大鼠取肺组织测定肺组织湿/干比。采用酶联免疫吸附测定（ELISA）法检测三组大鼠肺组织匀浆标本肿瘤坏死因子α（TNF-α）、白细胞介素1β（IL-1β）、NF-κB p65表达水平;荧光实时定量PCR检测三组大鼠肺组织TLR4 mRNA的表达。 结果假手术组、模型组及治疗组大鼠肺组织湿/干比[（4.00 ± 0.13）、（6.10 ± 0.05）、（5.80 ± 0.08）]、氧合指数[（315 ± 11）、（177 ± 7）、（200 ± 12）mmHg]、TNF-α[（6.05 ± 0.29）、（45.06 ± 0.52）、（27.09 ± 0.85）ng/L]、IL-1β[（8.02 ± 0.21）、（38.23 ± 0.81）、（32.73 ± 1.12）ng/L]及NF-κB p65[（0.375 ± 0.013）、（1.230 ± 0.045）、（0.988 ± 0.043）ng/L]表达水平比较,差异均有统计学意义（F = 480.891、255.309、4 245.262、1 918.168、564.842,P均< 0.001）。进一步两两比较发现,模型组和治疗组大鼠肺组织湿/干比、TNF-α、IL-1β、NF-κB p65表达水平均较假手术组大鼠显著升高（P均< 0.05）,治疗组大鼠肺组织湿/干比、TNF-α、IL-1β、NF-κB p65表达水平均较模型组大鼠显著降低（P均< 0.05）;而模型组和治疗组大鼠氧合指数均较假手术组大鼠显著降低（P均< 0.05）,治疗组大鼠氧合指数较模型组大鼠显著升高（P < 0.05）。荧光实时定量PCR结果显示,三组大鼠肺组织TLR4 mRNA表达水平比较,差异具有统计学意义（F= 224.538,P < 0.001）。进一步两两比较发现,与假手术组比较,模型组及治疗组大鼠肺组织TLR4 mRNA表达均显著升高（P均< 0.05）;而治疗组大鼠肺组织TLR4 mRNA表达较模型组显著降低（P < 0.05）。 结论萝卜硫素可减轻脓毒症急性肺损伤大鼠肺组织炎症反应、肺水肿程度,改善缺氧状态,对于肺组织具有一定保护作用,且其作用机制可能与干预TLR4/NF-κB信号途径相关。     

FTY720改善颅脑损伤大鼠神经功能的机制研究

目的探讨FTY720对颅脑损伤大鼠神经功能的影响及其相关机制研究。 方法60只大鼠分成假手术组、模型组和治疗组,每组20只,采用改进的Feeney自由落体损伤装置建立大鼠颅脑损伤模型。治疗组大鼠按1 mg/kg剂量予FTY720腹腔注射,假手术组及模型组大鼠予以腹腔注射1 ml生理盐水。术后24 h,每组各取10只大鼠断头处死,分离海马组织,采用Western-blotting检测核因子κB表达水平,采用免疫组织化学染色法检测大鼠小胶质细胞OX-42表达水平。同时采用前肢放置试验评分、平衡实验评分及改良神经功能缺损程度评分进行神经功能评估。 结果三组大鼠海马组织核因子κB蛋白表达水平（F=95.962,P<0.001）及小胶质细胞（F=108.853,P<0.001）比较,差异均有统计学意义。且模型组核因子κB蛋白及小胶质细胞OX-42表达水平较假手术组及治疗组明显增加（P均< 0.05）。同时,模型组大鼠术后7、14、21、28 d前肢放置试验评分[（7.0 ± 0.7）分vs.（6.3 ± 0.5）分,（5.9 ± 0.7）分vs.（5.0 ± 0.8）分,（4.9 ± 1.0）分vs.（3.8 ± 0.8）分,（3.7 ± 1.1）分vs.（2.3 ± 0.7）分;t=2.689、2.586、2.741、3.525,P=0.015、0.019、0.013、0.002]、平衡实验评分[（4.3 ± 0.7）分vs.（3.6 ± 0.7）分,（3.5 ± 1.1）分vs.（2.6 ± 0.7）分,（2.9 ± 0.9）分vs.（1.9 ± 0.7）分,（2.5 ± 0.7）分vs.（1.8 ± 0.6）分;t=2.278、2.212、2.762、2.333,P=0.035、0.040、0.013、0.031]及改良神经功能缺损程度评分[（10.1 ± 1.0）分vs.（8.7 ± 1.6）分,（8.8 ± 0.8）分vs.（7.5 ± 1.5）分,（7.3 ± 1.0）分vs.（5.6 ± 1.3）分,（5.7 ± 1.3）分vs.（4.1 ± 1.4）分;t=2.385、2.414、3.400、2.726,P=0.028、0.027、0.003、0.014]均明显高于治疗组。 结论FTY720可显著改善颅脑损伤大鼠神经功能,其作用机制可能与FTY720的中枢炎症抑制作用有关。     

血必净对脓毒性急性肾损伤大鼠肾小管细胞凋亡和相关蛋白表达的影响

目的探讨早期应用血必净对脓毒性急性肾损伤大鼠肾小管细胞凋亡,及相关蛋白B细胞淋巴瘤2（Bcl-2）和Bcl-2相关X蛋白（Bax）表达的影响。 方法54只雄性大鼠分为假手术组（Sham组）、脓毒症组（CLP组）、血必净组（CLP + XBJ组）三组,每组18只;以术后12、24和48 h作为时间观察点,将各组再分为3个亚组,每组6只。在各时间点检测大鼠的肌酐清除率（CrCl）、肾脏血流灌注量,并留取肾脏组织观察病理学变化,计算肾小管损伤评分,采用原位末端标记（TUNEL）法并通过计算积分光密度值（IOD）测定肾小管凋亡细胞,采用Western-blotting法测定肾脏髓质Bcl-2、Bax的变化。 结果三组大鼠的CrCl和肾脏血流灌注量在术后各时间点差异均有统计学意义（F = 6.405、18.821,P < 0.05）;且CLP + XBJ组在术后48 h时CrCl和肾脏血流灌注量明显高于CLP组[（2.1 ± 0.5）ml/min/100 g vs.（1.1 ± 0.3）ml/min/100 g,（159 ± 38）BPU vs.（79 ± 32）BPU;P均< 0.05]。三组大鼠肾小管损伤评分比较,不同时间点差异存在统计学意义（F = 5.461,P < 0.05）;且CLP + XBJ组与CLP组比较,24、48 h时评分均有显著下降[（1.6 ± 0.5）vs.（2.8 ± 0.8）,（1.8 ± 0.8）vs.（3.6 ± 0.6）;P均< 0.05]。三组大鼠各时间点凋亡细胞IOD值,差异存在统计学意义（F = 7.259,P < 0.05）;CLP + XBJ组各时间点的IOD值均明显小于CLP组[（26.6 ± 6.9）vs.（34.4 ± 5.0）,（38.2 ± 5.3）vs.（48.0 ± 5.8）,（37.6 ± 2.2）vs.（53.8 ± 6.7）;P均< 0.05]。同时,CLP + XBJ组能升高大鼠肾脏髓质Bcl-2的表达,抑制Bax的表达,维持Bcl-2/Bax的平衡,24、48 h时其Bcl-2[（1.30 ± 0.09）vs.（0.76 ± 0.09）,（2.12 ± 0.38）vs.（0.51 ± 0.07）;P均< 0.05]和Bax[（1.19 ± 0.37）vs.（1.95 ± 0.90）,（1.48 ± 0.15）vs.（2.69 ± 0.39）;P均< 0.05]的表达水平与脓毒症组相比差异均有统计学意义。 结论早期应用血必净可以减少肾小管细胞在脓毒症进程中的凋亡,改善脓毒性急性肾损伤大鼠肾脏的病理学改变,维持Bcl-2/Bax的平衡,减轻脓毒症导致的肾功能损害。     

miR-155对脓毒症急性肺损伤肺泡巨噬细胞IL-6、IL-10及MIP-2的影响

目的探讨微小核糖核酸155（miR-155）对脓毒症急性肺损伤（ALI）肺泡巨噬细胞白介素（IL）-6、IL-10及巨噬细胞炎性蛋白2（MIP-2）的影响。 方法健康清洁C57BL/6雄性小鼠（6~8周,18~20 g）15只,随机分为对照组、脓毒症组和miR-155 antagomir 3组,每组5只,其中miR-155 antagomir组小鼠中将miR-155 antagomir试剂经尾静脉注射,对照组和脓毒症组小鼠注射等量0.9%NaCl,观察24 h后,脓毒症组和miR-155 antagomir组采用盲肠结扎穿孔（CLP）法制备脓毒症ALI动物模型,对照组仅翻动盲肠进行对照,观察3组小鼠生命体征变化,模型制备6 h后,3组小鼠均取左肺下叶行苏木精-伊红（HE）方法进行染色,在光镜下观察肺病理形态变化,取右肺下叶检测干湿重比,应用酶联免疫吸附试验（ELISA）检测血浆IL-6、IL-10、MIP-2浓度。 结果HE染色结果表明：脓毒症组和miR-155 antagomir组小鼠肺内均出现肺泡结构破坏、炎症细胞浸润、间质增厚、出血,miR-155 antagomir组肺组织炎性表现较脓毒症组显著减轻。3组干湿重比结果显示：脓毒症组干湿重比［（0.16±0.01）%］明显低于对照组［（0.22±0.01）%］和miR-155 antagomir组［（0.19±0.01）%］,miR-155 antagomir组低于对照组,差异具有统计学意义（均P<0.05）。ELISA结果显示：脓毒症组的血浆IL-6浓度［（171.35±10.41）pg/ml］、MIP-2浓度［（299.71±19.82）pg/ml］显著高于对照组［（125.74±4.41）pg/ml;（214.00±14.93）pg/ml］和miR-155 antagomir组［（144.41±6.29）pg/ml;（270.38±11.96）pg/ml］,IL-10浓度［（283.58±19.90 ）pg/ml］显著低于对照组［（370.27±15.41）pg/ml］和miR-155 antagomir组［（333.30±16.49）pg/ml］,miR-155 antagomir组的血浆IL-6、MIP-2浓度高于对照组,IL-10浓度明显低于对照组,差异具有统计学意义（均P<0.05）。 结论脓毒症ALI时miR-155过度表达,过度表达的miR-155能促进肺泡巨噬细胞释放大量促炎因子而抑制抗炎因子的表达,引起促炎因子及抗炎因子失衡,发生不可控炎症反应,而miR-155 antagomir能够拮抗miR-155的表达,抑制肺泡巨噬细胞释放促炎因子IL-6及趋化因子MIP-2,上调抗炎因子IL-10的表达,进一步抑制中性粒细胞及肺泡巨噬细胞聚集,防止产生更多的炎症介质,有效控制肺部炎症反应的发生,对肺起到一定的保护作用。     

核苷酸结合寡聚化结构域样受体蛋白3炎性小体在脓毒症急性肾损伤大鼠肾脏组织的表达及其影响

目的探讨核苷酸结合寡聚化结构域样受体蛋白（NLRP3）炎性小体在脓毒症急性肾损伤（AKI）大鼠中的作用及其机制。 方法采用随机数字表法将18只雄性Wistar大鼠分为脂多糖（LPS）组、LPS +抑制剂组及阴性对照组3组,每组6只。LPS组大鼠给予腹腔内注射LPS（3.5 mg/kg）,LPS +抑制剂组大鼠腹腔内注射LPS（3.5 mg/kg）及半胱氨酸天冬氨酸蛋白酶1（Caspase-1）抑制剂Belnacasan（VX-765,100 mg/kg）,而阴性对照组大鼠则给予腹腔内注射0.3 mL等渗NaCl溶液。比较3组大鼠建模前及建模后24 h血清肌酐水平变化,采用酶联免疫吸附测定（ELISA）法检测3组大鼠建模24 h后血清白细胞介素1β（IL-1β）、IL-18及肿瘤坏死因子α（TNF-α）表达水平,采用Western-blotting检测3组大鼠建模24 h后NLRP3及Caspase-1蛋白表达水平。 结果3组大鼠建模前后血清肌酐水平比较,差异有统计学意义（F = 146.910,P < 0.001）。进一步两两比较发现,建模后,LPS +抑制剂组及阴性对照组大鼠血清肌酐水平均较LPS组显著降低[（1.57 ± 0.20）、（0.54 ± 0.39）、（2.31 ± 0.24）mg/L],且阴性对照组大鼠血清肌酐水平较LPS +抑制剂组更低（P均< 0.05）;而LPS组[（2.31 ± 0.24）mg/L vs.（0.53 ± 0.16）mg/L]及LPS +抑制剂组[（1.57 ± 0.20）mg/L vs.（0.56 ± 0.08）mg/L]大鼠建模后血清肌酐水平均较建模前显著升高（P均< 0.05）。LPS组、LPS +抑制剂组及阴性对照组大鼠血清IL-1β [（9.33 ± 1.16）、（1.93 ± 0.30）、（1.88 ± 0.30）ng/L]、IL-18 [（23.8 ± 2.8）、（19.6 ± 1.5）（16.6 ± 1.2）ng/L]、TNF-α [（42.3 ± 2.1）、（23.9 ± 2.5）、（23.5 ± 1.3）ng/L]及NLRP3蛋白[（2.04 ± 0.25）、（2.04 ± 0.27）、（1.49 ± 0.28）]和Caspase-1蛋白[（0.62 ± 0.07）、（0.51 ± 0.09）、（0.50 ± 0.09）]表达水平比较,差异均有统计学意义（F = 217.015、20.590、168.766、8.723、3.905,P均< 0.05）。进一步两两比较发现,LPS +抑制剂组及阴性对照组大鼠血清IL-1β、IL-18、TNF-α表达水平均较LPS组大鼠显著降低,且阴性对照组大鼠IL-18表达水平较LPS +抑制剂组更低（P均< 0.05）。阴性对照组大鼠NLRP3蛋白表达水平均较LPS组及LPS +抑制剂组显著降低,LPS +抑制剂组及阴性对照组大鼠Caspase-1蛋白表达水平均较LPS组显著降低（P均< 0.05）。 结论大鼠发生脓毒症时,通过激活炎性小体NLRP3,进而通过Caspase-1通路造成急性肾损伤。     

持续静脉泵注利多卡因对脓毒症大鼠急性肺损伤及炎症反应的影响

目的探讨利多卡因对脓毒症大鼠肺损伤及炎症因子表达的影响。 方法采用随机数字表法将60只雄性成年Sprague Dawley大鼠分为假手术组、盲肠结扎穿孔（CLP）组、利多卡因组和乌司他丁组,每组各15只。假手术组大鼠打开腹腔后缝合,其他各组采用CLP法制备脓毒症模型。利多卡因组大鼠在给予10 mg/kg的负荷剂量后,以10 mg·kg^-1·h^-1的剂量通过尾静脉持续泵注利多卡因3h;乌司他丁组大鼠进行CLP的同时,以100 000 U·kg^-1·h^-1的剂量通过尾静脉持续泵注乌司他丁3 h;假手术组和CLP组用等量等渗NaCl溶液代替。于CLP后24 h处死大鼠,采用酶联免疫吸附实验（ELISA）法测定血清中肿瘤坏死因子α（TNF-α）、白细胞介素6（IL-6）及高迁移率族蛋白B1（HMGB1）表达水平;实时荧光定量PCR检测肺组织HMGB1 mRNA表达水平;苏木素-伊红（HE）染色法观察各组大鼠肺组织病理变化。另取40只大鼠（每组10只）用于观察4组大鼠72 h死亡情况。 结果4组大鼠血清中TNF-α、IL-6、HMGB1及HMGB1 mRNA表达水平比较,差异均有统计学意义（F = 189.886、237.952、175.999、179.491,P均< 0.001）。进一步两两比较发现,与假手术组比较,CLP组、利多卡因组和乌司他丁组血清TNF-α、IL-6、HMGB1及HMGB1 mRNA表达水平均显著升高（P均< 0.05）;与CLP组比较,利多卡因组和乌司他丁组血清TNF-α、IL-6、HMGB1及HMGB1 mRNA表达水平均显著降低（P均< 0.05）;与利多卡因组比较,乌司他丁组IL-6表达水平显著升高（P < 0.05）。HE染色结果显示,假手术组大鼠肺泡大小均匀、结构完整,肺泡上皮细胞形态正常;CLP组大鼠肺泡间隔增厚、间质充血水肿、炎症细胞浸润、肺泡塌陷;而利多卡因组和乌司他丁组病理学改变较CLP组均明显减轻,肺组织轻度水肿,肺泡及肺间质出现少量炎症。四组大鼠死亡构成比（0 /10、9/1、4/6、3/7）比较,差异有统计学意义（χ²=17.500,P < 0.001）。CLP组、利多卡因组和乌司他丁组大鼠死亡构成比均较假手术组显著升高（P均<0.008）;利多卡因组和乌司他丁组大鼠死亡构成比均较CLP组显著降低（P均<0.008）;而利多卡因组和乌司他丁组大鼠死亡构成比比较,差异无统计学意义（P > 0.008）。 结论持续静脉泵注利多卡因可以有效降低脓毒症大鼠炎症因子TNF-α、IL-6及HMGB1的表达,抑制肺组织中HMGB1 mRNA表达量,减轻脓毒症对肺组织的损伤,有效提高动物存活率,其减轻脓毒症炎症反应及肺保护作用疗效与乌司他丁相似。     

清热燥湿方对急性肺损伤大鼠中性粒细胞弹性蛋白酶和肿瘤坏死因子-α蛋白及mRNA的影响

目的探讨清热燥湿方对脂多糖（LPS）诱导的急性肺损伤（ALI）大鼠支气管肺泡灌洗液（BALF）中中性粒细胞弹性蛋白酶（NE）和肺组织肿瘤坏死因子-a（TNF-a）蛋白及mRNA表达的影响。方法将40只雄性Wistar大鼠随机分为对照组、模型组、地塞米松组、清热燥湿方组,每组再分为4h和8h两个亚组,每个亚组5只。尾静脉注射LPS10mg／kg制备大鼠ALI模型。地塞米松组和清热澡湿方组分别于制模前灌胃地塞米松0．45mg／kg和清热燥湿方6．48g／kg。分别采用酶联免疫吸附法、免疫组化法及实时荧光定量聚合酶链反应（PCR）检测NE含量和TNF—a蛋白及mRNA的表达;同时进行肺组织病理观察。结果与模型组相比,清热燥湿方组4h、8hBALF中NE含量均显著降低（均P〈0．01）;地塞米松组和清热燥湿方组4h时TNF—a蛋白表达及4h、8h时TNF—amRNA表达均显著降低（P〈0．05或P〈0．01）。组织病理学观察显示,模型组大鼠肺组织出现大片出血及坏死;清热燥湿方组大鼠肺组织病理损伤程度较模型组减轻。结论清热燥湿方能减轻LPS致ALI大鼠肺组织损伤,其机制可能与清热燥湿方能降低LPS致ALI大鼠体内NE含量和TNF—a的表达有关。     

Effect of hyperbaric oxygen on endotoxin-induced lung injury in rats

Oxygen therapy remains the main component of the ventilation strategy for treatment of patients with acute lung injury. Hyperbaric oxygen therapy (HBO(2)) is the intermittent administration of 100% oxygen at pressure greater than sea level and has been applied widely to alleviate a variety of hypoxia-related tissue injuries. The purpose of this study was to evaluate the effect of hyperbaric oxygen on acute lung injury induced by intratracheal spraying of lipopolysaccharide (LPS) in rats. Male Sprague-Dawley rats underwent implantation of a carotid artery catheter under general anesthesia. Aerosolized LPS was delivered twice into the lungs via intratracheal puncture. Animals were either breathing room air (n = 27) or subjected to hyperbaric oxygen (HBO(2)) exposure (n = 27) 1 h after LPS spraying. Acute lung injury was evaluated 5 h and 24 h later. Compared with the control group, intratracheal spraying of LPS caused profound hypoxemia, greater wet/dry weight ratio (W/D) of the lung (5.67 +/- 0.22 vs. 4.98 +/- 0.19), and higher protein concentration (1706 +/- 168 vs. 200 +/- 90 mg/L) and LDH activity (129 +/- 30 vs. 46 +/- 15, mAbs/min) in bronchoalveolar lavage (BAL) fluid. Intratracheal spraying of LPS also caused significant WBC sequestration in the lung tissue. HBO2 treatment significantly reverted hypoxemia, reduced lung injury measures evaluated at 5 and 24 h, and enhanced 24-h animal survival rate (chi = 5.08, P = 0.024). The malondialdehyde (MDA) concentrations in lung tissue and serum were both increased after LPS spraying. Neither single HBO(2) therapy nor five sequential daily treatments enhanced MDA production in lung tissue or serum. Our results suggested that hyperbaric oxygen might reduce acute lung injury caused by intratracheal spraying of LPS in rats. This treatment modality is not associated with enhancement of oxidative stress to the lung.     

Role of p38 mitogen-activated protein kinase in lung injury after burn trauma

This study was undertaken to evaluate the effect of SB203580, a specific p38 mitogen-activated protein (MAP) kinase inhibitor, on burn-induced lung injury as well as the release of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta in rats to characterize the role of p38 MAP kinase in lung injury after burn trauma. Sprague-Dawley rats were divided into three groups: 1) sham group, or rats who underwent sham burn; 2) control group, or rats given third-degree burns over 30% total body surface area (TBSA) and lactated Ringer solution for resuscitation; and 3) SB203580 group, or rats given burn injury and lactated Ringers solution with SB203580 inside for resuscitation. Pulmonary injury was assessed at 24 h by pulmonary capillary permeability determined with fluorescein isothiocyanate-labeled albumin and lung histologic analysis. TNF-alpha and IL-1beta protein in bronchoalveolar lavage fluid and serum were measured by enzyme-linked immunosorbent assay and p38 MAP kinase was activity determined in lung by Western blot analysis. These studies showed that significant activation of p38 MAP kinase at 24 h postburn compared with control. Burn trauma resulted in increased pulmonary capillary leakage permeability, elevated levels of TNF-alpha and IL-1beta in bronchoalveolar lavage fluid and serum, and worsened histologic condition. SB203580 inhibited the activation of p38 MAP kinase, reduced the levels of TNF-alpha and IL-1beta, and prevented burn-mediated lung injury. These data suggest that p38 MAP kinase activation is one important aspect of the signaling event that may mediate the release of TNF-alpha and IL-1beta and contributes to burn-induced lung injury.     

Exacerbation by granulocyte colony-stimulating factor of prior acute lung injury: implication of neutrophils

OBJECTIVE: Granulocyte colony-stimulating factor is widely prescribed to hasten recovery from cancer chemotherapy-induced neutropenia and has been reported to induce pulmonary toxicity. However, circumstances and mechanisms of this toxicity remain poorly known. DESIGN: To reproduce a routine situation in cancer patients receiving chemotherapy, we investigated the mechanisms underlying granulocyte colony-stimulating factor-induced exacerbation of alpha-naphthylthiourea-related pulmonary edema. SETTING: Laboratory research unit. SUBJECTS: Male specific-pathogen-free Sprague-Dawley rats. INTERVENTIONS: The effects of granulocyte colony-stimulating factor given alone or after alpha-naphthylthiourea used to induce acute lung injury were investigated. MEASUREMENTS AND MAIN RESULTS: Lung injury was assessed based on neutrophil sequestration (myeloperoxidase activity in lung tissue) and influx into alveolar spaces (bronchoalveolar lavage fluid cell quantification) and on edema formation (wet/dry lung weight ratio) and alveolar protein concentration into bronchoalveolar lavage fluid. Tumor necrosis factor-alpha and interleukin-1beta were measured in serum, lung homogenates, and isolated alveolar macrophage supernatants. In control rats, granulocyte colony-stimulating factor (25 microg/kg) significantly elevated circulating neutrophil counts without producing alveolar recruitment or pulmonary edema. alpha-Naphthylthiourea significantly increased the wet/dry lung weight ratio (4.68 +/- 0.04 vs. 4.38 +/- 0.07 in controls, p=.04) and induced alveolar protein leakage. Adding granulocyte colony-stimulating factor to alpha-naphthylthiourea exacerbated pulmonary edema, causing neutrophil sequestration in pulmonary vessels, significantly increasing lung myeloperoxidase activity (12.7 +/- 2.0 mOD/min/g vs. 1.1 +/- 0.4 mOD/min/g with alpha-naphthylthiourea alone; p<.0001), and increasing proinflammatory cytokine secretion. alpha-Naphthylthiourea-related pulmonary edema was not exacerbated by granulocyte colony-stimulating factor during cyclophosphamide-induced neutropenia or after lidocaine, which antagonizes neutrophil adhesion to endothelial cells. Tumor necrosis factor-alpha and interleukin-1beta concentrations in alveolar macrophage supernatants and lung homogenates were significantly higher with alpha-naphthylthiourea + granulocyte colony-stimulating factor than with either agent alone, and anti-tumor necrosis factor-alpha antibodies abolished granulocyte colony-stimulating factor-related exacerbation of alpha-naphthylthiourea-induced pulmonary edema. In rats with cyclophosphamide-induced neutropenia, tumor necrosis factor-alpha concentrations in alveolar macrophage supernatants and lung homogenates were significantly decreased compared with rats without neutropenia. CONCLUSION: Granulocyte colony-stimulating factor-related pulmonary toxicity may involve migration of neutrophils to vascular spaces, adhesion of neutrophils to previously injured endothelial cells, and potentiation of proinflammatory cytokine expression.     

参附注射液对大鼠内毒素性急性肺损伤的保护作用

目的:观察参附注射液(SF)对大鼠内毒素性急性肺损伤(ALI)时肺组织湿/干重比(W/D)等的影响,探讨其对ALI是否具有保护作用.方法:采用大鼠气管内滴注内毒素诱导ALI模型,30只大鼠随机分为NS组、LPS组、SF组,每组10只.观察每组肺组织W/D、肺泡灌洗液中性粒细胞比、蛋白含量、血清NO、肺组织丙二醛(MDA)含量及比较动脉血气分析的结果.同时观察肺组织病理形态学改变.结果:与NS组比较,LPS组、SF组的肺组织W/D、肺泡灌洗液中性粒细胞比、蛋白含量、肺组织MDA和血清NO显著增加,而PaO2和HCO3-明显降低(P<0.01);与LPS组比较,SF组以上指标显著降低而PaO2和HCO3-明显升高(P<0.05或P<0.01).病理学检查显示SF组肺组织损伤程度较LPS组明显减轻.结论:SF对内毒素性ALI具有防治作用.     

Liposome-encapsulated hemoglobin does not exacerbate endotoxin-induced lung injury

OBJECTIVE: To test the hypothesis that liposome encapsulated hemoglobin (LEH), an experimental oxygen-carrying fluid, exacerbates endotoxin-induced lung injury in the rat. DESIGN: Prospective, randomized animal study. SETTING: University animal laboratory. METHODS: Anesthetized Sprague-Dawley rats (n = 8-13) were infused with LEH (10% of estimated total blood volume) or vehicle (0.9% NaCl). Thirty minutes later, Escherichia coli endotoxin (3.6 mg/kg, i.v.) or vehicle (0.9% NaCl) was administered, and skeletal muscle oxygen tension as well as lung injury were assessed at 2, 4, and 8 hrs. Oxygen tension was measured using a miniaturized thin film oxygen sensor placed in the rectus abdominis muscle, and lung injury was evaluated by determining lung weights, lung myeloperoxidase activity, lung tissue tumor necrosis factor-alpha level, and protein concentration in bronchoalveolar lavage fluid. RESULTS: The intravenous bolus injection of E. coli endotoxin elevated lung water content (33% +/- 5%; p < .01 vs. sham controls), myeloperoxidase activity (56% +/- 6%; p < .01), and tumor necrosis factor-alpha production (1320 +/- 154 pg/g lung tissue; p < .05 vs. undetected levels in sham controls), as well as induced protein accumulation in bronchoalveolar lavage fluid (258% +/- 38%; p < .01) and skeletal muscle hypoxia (52 +/- 8 mm Hg; p < .05). Pretreatment with LEH, which when infused alone did not induce lung injury, had no effect on these responses. CONCLUSION: In this specific model of endotoxin-induced lung injury, LEH does not exacerbate microvascular leakage and leukosequestration, the hallmarks of adult respiratory distress syndrome.     

小窝蛋白-1、IL-8在机械通气致大鼠急性肺损伤中的作用研究

目的通过观察不同时间段肺组织中小窝蛋白-1(cav-1)及IL-8的表达水平,探讨二者在机械通气所致肺损伤(VILI)发生中的作用?方法雄性Wistar大鼠24只,按随机数字表法分为3组:对照组、大潮气量通气0.5 h组(H-VT0.5 h组)和大潮气量通气2 h组(H-VT2 h组)。在光镜下观察各组大鼠肺组织病理学改变,测定BALF总蛋白(TP)含量和肺湿/干重比值(W/D),采用免疫组织化学染色法测定肺组织cav-1及IL-8的表达水平,并进行相关性分析。结果 H-VT0.5 h组大鼠肺组织cav-1蛋白表达水平明显高于对照组(P<0.01),而BALF总蛋白含量、W/D比值及肺组织IL-8表达水平与对照组比较无统计学意义(P>0.05),且肺组织无明显病理损伤改变。H-VT2 h组大鼠BALF总蛋白含量、W/D比值及肺组织cav-1和IL-8蛋白表达量均明显高于对照组和H-VT0.5 h组(均P<0.01),同时肺组织可见明显病理损伤改变。相关性分析结果显示,各组大鼠肺组织cav-1蛋白表达水平与IL-8表达水平之间呈正相关(r=0.737,P<0.01)。结论 cav-1在VILI发生中的作用可能具有两面性,早期以保护作用为主,后期以损伤作用为主,而损伤作用可能与IL-8的释放激活中性粒细胞有关。     

电刺激迷走神经对脓毒症大鼠急性肺损伤的影响

目的探讨电刺激迷走神经激活胆碱能抗炎通路对脓毒症大鼠急性肺损伤的影响。方法采用盲肠结扎穿孑L术（CLP）复制脓毒症大鼠模型。40只雄性SD大鼠被随机分为假手术（SHAM）组、CLP组、迷走神经切断（VGX）组和迷走神经刺激（STM）组，每组10只。CLP组行CLP；VGX组行CLP后离断双侧颈部迷走神经干；STM组在VGX组处理的基础上行左侧迷走神经干远端电刺激。所有动物于制模成功后18h经颈动脉放血处死，检测血浆肿瘤坏死因子-α（TNF-α）浓度、动脉血乳酸及血气分析；计算肺湿／干重比值；观察肺组织病理学改变及超微结构改变。结果与SHAM组比较，CLP组和VGX组血浆TNF-α浓度、动脉血乳酸值、动脉血二氧化碳分压（PaCO2）、肺湿／干重比值均升高，pH、动脉血氧分压（PaO2）以及剩余碱（BE）值均降低（P〈0．05或P〈0．01）。与CLP组比较，STM组血浆TNF—d浓度、动脉血乳酸值、PaCO2、肺湿／干重比值均降低，pH、PaO2以及BE值升高（P〈0．05或P〈0．01）。肺组织病理学和电镜下超微结构改变均显示：CLP组肺损伤较SHAM组明显加重，而STM组肺损伤较CLP组、VGX组明显减轻。结论通过电刺激迷走神经激活胆碱能抗炎通路，可起到保护脓毒症大鼠急性肺损伤的作用。