中性粒细胞凋亡延迟在脂多糖所致大鼠急性肺损伤发病机制中的作用

目的 探讨急性肺损伤时肺组织及外周血中性粒细胞（PMN）凋亡和坏死的发生规律及其与肺损伤的关系。以及可能涉及的机制。方法 Wistar大鼠50只,腹腔注射脂多糖（LPS,O55B5,3mg/kg)造成大鼠急性肺损伤,分为LPS注射后2h组、4h组、8h组,12h组及正常对照组。于预定时相取血及支气管灌洗液,密度梯度离心分离PMN,用流式细胞仪测定凋亡,坏死细胞比例及呼吸焊发功能,同时测定乳酸脱氢酶（LDH）含量,肺通透指数,肿瘤坯 煞费苦心因子（TNF）、白细胞介素（IL）1β、IL-6含量和Ca^2 浓度。结果 ALI大鼠肺灌洗液中PMN凋亡,坏死比例的变化与外周血不同,主要表现为存活细胞比例增加,凋亡延迟,肺灌洗液中TNF、IL-1β、IL-6含量明显高于外周血,且持续时间较长,同时,肺灌洗液LDH明显升高,肺通透指数显著增加。结论 肺组织中高浓度的细胞因子和短暂升高的Ca^2 使游出的PMN的正常凋亡途径发生障碍,造成PMN持续处于激活状态及毒性内容物的持续释放,与肺组织损伤有密切关系。     

中性粒细胞在大鼠急性重症胰腺炎肺损伤中的作用机制

目的:探讨急性重症胰腺炎(ASP)合并急性肺损伤时肺泡灌洗液中性粒细胞(PMN)凋亡和坏死的发生规律及可能涉及的作用机制.方法:选取雄性SD大鼠48只,分为ASP实验组(24只)、对照组(24只).实验组大鼠穿刺胰胆管并注入35g/L牛磺胆酸钠制作ASP大鼠模型,分别在制模后3,6,12 h剖杀,于预定时相取支气管灌洗液,密度梯度离心分离PMN,用流式细胞仪测定PMN凋亡、坏死比例,同时测定乳酸脱氢酶(LDH)含量、肺通透指数.结果:ASP组大鼠肺灌洗液中PMN存活细胞比例增加(P＜0.01),凋亡延迟.同时,肺灌洗液LDH明显升高(P＜0.01),肺通透指数显著增加(P＜0.01).结论:ASP合并急性肺损伤时,PMN凋亡延迟,造成PMN持续处于激活状态及毒性内容物的持续释放,与急性肺损伤密切相关.     

Pro-apoptotic role of NF-κB pathway inhibition in lipopolysaccharide stimulated polymorphonuclear neutrophils

Objective To investigate the role of nuclear factor kappa B (NF-κB) pathway inhibition in lipopolysaccharide (LPS)-stimulated apoptosis of polymorphonuclear neutrophils (PMNs).Methods Rats with acute lung injury induced by LPS intratracheal instillation and cultured human venous PMNs were studied. Pyrrolidine dithiocarbamate (PDTC) and gliotoxin were used as NF-κB inhibitors. Additionally, to explore the role of extracellularly regulated protein kinase as an upstream signal in NF-κB pathway on regulating LPS-stimulated PMN apoptosis, PD098059, the specific inhibitor of extracellularly regulated protein kinase, was also applied. The lung injury was determined by protein content and PMN numbers in bronchoalveolar lavage fluid. PMN apoptosis was measured by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) end labeling and DNA fragmentation. IκBα degradation was analyzed by Western blot. NF-κB DNA binding activity was detected by an electrophoretic mobility shift assay.Results (1) The increase of protein content and PMN numbers in bronchoalveolar lavage fluid induced by LPS (100μg per rat) intratracheal instillation were alleviated by PDTC (50, 100, or 200mg/kg, i. p. ) in a dose-dependent manner. (2) PMNs apoptosis in vivo or in vitro was delayed by LPS, and accelerated by PDTC, gliotoxin or PD098059 pretreatment. (3) IκBα degradation and increased NF-KB DNA binding activity mediated by LPS were inhibited by PDTC, gliotoxin or PD098059 pretreatment.Conclusion Inhibition of either NF-κB itself or the upstream signals in NF-κB pathway such as extracellularly regulated protein kinases has therapeutic effect on LPS-induced acute lung injury, in which the dysregulation of PMN apoptosis plays an important role.     

TNF-α、IL-8与急性重症胰腺炎肺损伤中PMNs凋亡延迟的相关性研究

目的探讨肿瘤坏死因子-α(TNF-α)和白细胞介素-8(IL-8)在急性重症胰腺炎(acute severe pancreatitis,ASP)合并急性肺损伤中中性粒细胞(polymorphonuclear leukocyte,PMNs)凋亡延迟的相关性及其机制。方法选取雄性SD大鼠48只,穿刺胆胰管并注入3.5%牛磺胆酸钠制作ASP合并急性肺损伤大鼠模型,分为牛磺胆酸钠注射后3、6、12 h及对照组。病理检测胰腺及肺组织;于预定时相取支气管灌洗液,密度梯度离心分离PMNs,流式细胞仪测定PMNs凋亡、坏死比例;ELISA检测灌洗液中TNF-α及IL-8的含量;检测NF-κB在肺组织中的表达。结果 ALI大鼠肺灌洗液中PMNs凋亡、坏死比例增加,凋亡延迟。支气管-肺泡灌洗液中的TNF-α及IL-8的含量较对照组显著增加,灌洗液中细胞TNF-α及IL-8 mRNA表达增加,不同干预时间组间具有显著差异,具有时间依赖效应;肺组织中NF-κB的表达显著增加。结论TNF-α、IL-8在ASP合并急性肺损伤中可能发挥一定的作用。     

Treatment of acute lung injury due to sea water aspiration in dogs by early massive bronchoalveolar lavage: an experimental study]

OBJECTIVE: To investigate the therapeutic effects of massive bronchoalveolar lavage at early stage of acute lung injury induced by sea water aspiration. METHODS: Twelve mongrel dogs were subjected to sea water infusion of the entire lungs and were subsequently randomized into 2 groups. The dogs in group A received intravenous saline transfusion 24 h after injury, while those in group B underwent bronchoscopic lavage of injured lungs with 450 ml 0.45% saline 15 min after injury. Unassisted breathing was maintained in both groups, and the gas exchange function of the bilateral lungs and the levels of lactate dehydrogenase, alkaline phosphatase in the bronchoalveolar fluid were observed, with the hemodynamics indices monitored continuously. The lungs of the dogs were finally removed for morphological study under both light and electron microscopes, and the water content and wet- to dry-weight ratio of the lung tissues were determined. RESULTS: A total lavage volume of approximately 30 ml/kg x b.w. was used, and the liquid volume remaining in the lungs after operation ranged from 80 to 120 ml. All the dogs manifested significant declination in pulmonary function after the drowning. PaO2 in group B decreased significantly soon after the lavage but then increased gradually to a higher levels than group A. The dogs in group B had smaller lung water content and lower levels of lactate dehydrogenase and alkaline phosphatase in the bronchoalveolar fluid, showing improved oxygenation in comparison with group A. The inflammatory reaction and edema in lungs were also markedly alleviated in group B. CONCLUSION: Treatment with massive lung lavage in early stage after sea water aspiration can effectively protect the lung tissues from damage and alleviate the inflammatory reaction and pulmonary edema, helping to improve the lung function.     

创伤后肺内炎性细胞凋亡与继发性坏死的观察及意义

目的 探讨严重创伤后肺内炎性细胞凋亡与继发性坏死在急性肺损伤发病机制中的地位和作用。方法 复制大鼠多发骨折合并休克模型,采用Annexin-V和PI双标法经流式细胞仪检测创伤后肺泡灌洗液中凋亡与坏死炎性细胞的数量变化,测定细胞分类计数及肺通透指数并作比较。结果伤后动物肺泡灌洗液中巨噬细胞数量减少,而白细胞数量增加。伤后凋亡炎性细胞数量增加,于伤后3h达到高峰。部分凋亡炎性细胞发生继发性坏死,其数量进行性升高并与肺通透指数变化显著相关（r=0.90,P<0.01）。结论 严重创伤后肺泡内炎性细胞发生凋亡,可能因为继发性坏死致炎性内容物外泄而引发急性肺损伤。     

激活粒细胞对大鼠离体心脏再灌注损伤的实验研究

本实验采用大鼠离体心脏模型，探讨激活粒细胞对大鼠离体心脏再灌注损伤的作用机制。实验过程观察冠状动脉流量，冠状动脉阻力，冠状动脉流出液中乳酸脱氢酶的活性及再二醛的含量。实验完毕后对心肌进行组织学检查及超微结构观察。     

猪钢珠弹伤后血浆及肺组织的脂质过氧化与粒细胞活性氧产生量

本实验观测了猪双后肢高速钢珠弹伤后外周血多形核粒细胞(Polymorphonuclear Leukocytes,PMNs)活性氧产生量、血浆和肺组织匀浆及支气管肺泡灌洗液(Bronchoalveolar Lavage Fluid,BALF)中脂质过氧化物(Lipid Peroxides,LPO)代谢产物丙二醛(Malonyldialdehyde,MDA)含量的变化。结果提示,外周血PMNs自发和在酵母多糖刺激下产生的活性氧均增加,分别在伤后4h、8h达峰值,然后逐渐减少;血浆MDA变化也经历了相似的过程,并与PMNs自发活性氧产生量的变化密切相关;肺组织匀浆和BALF中MDA在伤后24h时较正常的明显增加。文章对实验结果,特别是PMNs的功能与脂质过氧化损伤间的关系进行了讨论。     

大鼠胸部撞击致肺损伤模型的建立

目的 建立一种胸部撞击致肺挫伤的大鼠模型.方法 将84只SD大鼠随机分成7组(n=12),采用自制的胸部撞击装置,用不同撞击能量(2.7、2.0、1.8、1.5、1.2、0.9和0 J)对大鼠胸部进行撞击造成双侧肺损伤.监测撞击前后大鼠循环和呼吸功能变化.撞击120 min后处死大鼠,开胸行创伤评分,观察心肺组织形态学变化,并进行病理学评分,计算肺组织湿干比和肺泡灌洗液蛋白含量.结果 用1.2J能量撞击大鼠胸部可致理想的双侧肺损伤而无明显心脏损伤,动物死亡率较低.结论 采用自制胸部撞击装置建立的大鼠双侧肺损伤模型可以较好地模拟胸部撞击后双侧肺挫伤伤情,可用1.2J的撞击能量进行后续实验研究.     

Mesenchymal Stem Cell Attenuates Neutrophil-predominant Inflammation and Acute Lung Injury in an In Vivo Rat Model of Ventilator-induced Lung Injury

Background:Subsequent neutrophil (polymorphonuclear neutrophil [PMN])-predominant inflammatory response is a predominant feature of ventilator-induced lung injury (VILI),and mesenchymal stem cell (MSC)...     

氢气对百草枯中毒大鼠急性肺损伤的保护作用

目的:探讨氢气对百草枯中毒大鼠急性肺损伤的保护作用。方法:24只大鼠随机分为3组:对照组、百草枯组和氢气组,百草枯组和氢气组腹腔注射百草枯(35mg/kg),氢气组于注射后立即开始吸入含2%氢气的空气。72h后检测肺湿/干比、肺泡灌洗液PMN、PaO2、肺损伤评分、肺组织丙二醛含量。结果:与对照组比较,百草枯组、氢气组肺湿/干比、肺泡灌洗液PMN、肺损伤评分、肺组织丙二醛含量升高,PaO2降低;与百草枯组比较,氢气组肺湿/干比、肺泡灌洗液PMN、肺损伤评分、肺组织丙二醛含量降低,PaO2升高。结论:吸入氢气能够通过抑制脂质过氧化,抑制白细胞在肺部的聚集,从而减轻百草枯中毒后引起的急性肺损伤。     

硫化氢调节急性肺损伤大鼠肺泡上皮细胞凋亡

Background Acute lung injury (ALI) is a common syndrome associated with high morbidity and mortality in emergency. Cell apoptosis plays a key role in the pathogenesis of ALI. Hydrogen sulfide (H2S) plays a protective role during acute lung injury. We designed this study to examine the role of H2S in the lung alveolar epithelial cell apoptosis in rats with acute lung injury. Methods Sixty-nine male Sprague Dawley rats were used. ALI was induced by intra-tail vein injection of oleic acid (OA). NaHS solution was injected intraperitonally 30 min before OA injection as NaHS pretreatment group. Single sodium hydrosulfide pretreatment group and control group were designed. Index of quantitative assessment (IQA) and the percentage of polymorphonuclear leucocyte (PMN) cells in the bronchoalveolar lavage fluid (BALF) were calculated. H2S level in lung tissue was measured by sensitive sulphur electrode. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Fas protein was measured by immunohistochemical staining. Results The level of endogenous H2S in lung tissue decreased in the development of ALI induced by OA injection. Apoptosis and Fas protein in alveolar epithelial cells increased in ALI of rats but NaHS lessened apoptosis and Fas protein expression in alveolar epithelial cells of rats with ALI. Conclusion Endogenous H2S protects rats from oleic acid-induced acute lung injury probably by inhibiting cell apoptosis.     

血红素加氧酶-1重组乳酸乳球菌灌胃对内毒素诱导大鼠急性肺损伤的作用

目的:利用基因工程原理合成携带血红素加氧酶-1(HO-1)基因的乳酸乳球菌,给正常大鼠灌胃后,观察其对内毒素诱导大鼠急性肺损伤的保护效应。方法:随机将30只健康清洁级SD大鼠分为对照组(LPS组,n=10)、携带HO-1的乳酸乳球菌灌胃组(HO组,n=10,LPS模型建立前24 h灌胃)、拮抗剂组[锌原卟啉(ZnPP)组,n=10,HO灌胃24 h后,LPS模型建立前1 h腹腔注射ZnPP 10μmol/kg];LPS模型建立后4 h取材,比较各组动物支气管灌洗液(BALF)中髓过氧化物酶(MPO)活性、中性粒细胞(PMN)计数、肺组织湿干重比(W/D)、肺组织MPO活性,并在光镜下观察肺组织病理学改变。结果:与LPS组比较,HO组BALF中MPO、PMN计数和肺组织W/D均降低(P<0.05),肺组织病理学损伤减轻;与HO组比较,ZnPP组BALF中MPO、PMN计数和肺组织W/D均升高(P<0.05),肺组织病理学损伤加重;ZnPP组与LPS组比较差异无统计学意义(P>0.05)。结论:预先给大鼠用携带HO-1基因的乳酸乳球菌灌胃,可对内毒素诱导急性肺损伤大鼠产生一定的保护作用。     

川芎嗪对幼兔肺缺血再灌注损伤的保护作用

目的:探讨川芎嗪(LZ)对幼兔肺缺血再灌注损伤中肺的保护作用。方法:将36只实验用幼兔随机分成缺血再灌注组(I/R)、假手术组(S)和川芎嗪组(LZ60mg/kg),每组12只。建立在体幼兔肺缺血再灌注模型,并检测肺组织中超氧化物歧化酶(SOD),丙二醛(MDA)及髓过氧化物酶(MPO)的水平。测定肺泡灌洗液(BALF)中性粒细胞(PMN)计数、计算肺湿干重比(W/D)和光镜下观察肺组织病理改变。结果:I/R组与S组相比,SOD活性下降,W/D、MDA含量及MPO活性均显著增加,肺组织病理损伤明显。LZ组与I/R组相比,W/D、SOD活性增加,MDA含量、MPO活性降低及再灌注肺BALF中性粒细胞计数LZ组低于I/R组(P<0.05),肺组织病理损伤明显减轻。结论:川芎嗪能明显减轻幼兔肺缺血再灌注损伤,其作用机制可能与抑制中性粒细胞在肺内积聚、减轻氧自由基造成的肺损伤有关。     

大剂量氨溴索对海水浸泡致急性肺损伤犬体内SP—A、SP—B含量的影响

目的：探讨大剂量氨溴索对胸部开放伤后海水浸泡致急性肺损伤（ALI）犬体内肺表面活性蛋白A和B（SP—A、SP—B）含量的影响。方法：胸腔注入海水制备犬ALI模型,随机分为对照组（CG）及氨溴索治疗组（AG）,AG犬在海水浸泡10min后静脉注射12mg／kg的氨溴索,CG组以等量生理盐水代替,观察伤后不同时间点血清及肺组织中SP—A、SP—B含量的变化。结果：致伤后6h后氨溴索治疗组及对照组血清中SP—A、SP—B含量均较实验前明显增高（P〈0．01）,但两组间无统计学差异（P〉0．05）;而氨溴索治疗组支气管肺泡灌洗液（BALF）中SP—A、SP—B的含量明显高于对照组（P〈0．01）。结论：氨溴索能诱导胸部开放伤后海水浸泡致ALI犬肺内SP—A、SP—B的表达。     

Hydrogen sulfide donor regulates alveolar epithelial cell apoptosis in rats with acute lung injury

Background Acute lung injury (ALl) is a common syndrome associated with high morbidity and mortality in emergency medicine.Cell apoptosis plays a key role in the pathogenesis of ALl.Hydrogen sulfide (H...     

大鼠体外循环模型的建立及其效果评价

目的探讨大鼠动-静脉体外循环(extracorporeal circulation,ECC)模型是否能模拟临床体外循环造成的特征性炎性反应和器官损伤。方法 SD大鼠麻醉,右颈总动脉、左股静脉插管建立循环通路后随机分为2组:ECC组大鼠采用右颈总动脉-左股静脉转流2h,观察2h;Sham组大鼠插管后仅进行血液稀释而不行旁路循环,观察4h。实验结束后取标本测定血常规、血浆炎性细胞因子含量、动脉血气、支气管肺泡灌洗液中炎性因子和肺组织含水量;并使用流式细胞术测定循环内皮细胞数量;另取肺组织做HE染色。结果 ECC后2h,ECC组大鼠仍能保持正常红细胞数量,而白细胞数量、血浆中肿瘤坏死因子-α(TNF-α)、中性粒细胞弹性蛋白酶(NE)水平、循环内皮细胞数量均高于Sham组(P<0.05)。肺损伤指标显示:ECC组动物肺氧合指数低于300 mmHg(1mmHg=0.1333kPa),并低于Sham组(P<0.05),达到临床急性肺损伤诊断标准;而支气管肺泡灌洗液内TNF-α、肺水含量均高于Sham组(P<0.05),肺组织内可见大量炎性细胞浸润,肺泡膜明显增厚。结论经右颈总动脉、左股静脉插管能成功建立大鼠ECC模型,该模型影响因素单一,成功率高,仅转流2h即能诱导出全身炎性反应综合征和炎性相关急性肺损伤,因此适于研究ECC炎性反应对组织器官功能的影响。     

机动车尾气颗粒物对实验动物肺损伤作用的研究及比较

本实验采用气管注入染毒，研究及比较了汽车尾气颗粒物对肺的毒性作用。染毒２４小时后进行肺灌洗液成分分析，结果显示剂量为１．５ｍｇ／ｋｇ时，大鼠肺灌洗液乳酸脱氢酶活性增加，并随剂量增加，灌洗液中酸性磷酸酶、碱性磷酸酶活性和白蛋白及唾液酸含量也明显升高，肺泡巨噬细胞数减少，表明颗粒物对肺组织有明显损伤作用。汽油车尾气颗粒物的毒性作用高于柴油车尾气颗粒物。     

尿酸对油酸型家兔急性肺损伤的疗效观察

目的 :观察尿酸对油酸诱导的家兔急性肺损伤模型的治疗效果。方法 :30只家兔分 4组 ,分别为对照组、急性肺损伤组、尿酸组、生理盐水组。从家兔耳缘静脉注入油酸后造成急性肺损伤 ,用尿酸治疗观察呼吸频率、动脉血氧分压 (PaO2 )、支气管肺泡灌洗液 (BALF)中白蛋白的含量、细胞计数、分类、肺湿重和病理改变。结果 :所有家兔在油酸致伤后呼吸频率均较损伤前加快 (P <0 .0 1) ;尿酸组呼吸频率和急性肺损伤组相比 ,增加较少 ,差异无显著性 (P >0 .0 5 )。致伤后所有家兔的PaO2较致伤前均迅速下降 (P <0 .0 1) ;在损伤后 2 4h和 4 8h ,尿酸组PaO2 降低程度低于急性肺损伤组 (P <0 .0 1和P <0 .0 5 )。油酸致伤后 ,所有家兔BALF中白蛋白含量、多形核粒细胞计数、多形核粒细胞占白细胞总数的比例、肺湿重均较对照组明显增加 (P <0 .0 1) ,尿酸组各指标均低于急性肺损伤组 (P <0 .0 5～P <0 .0 1)。油酸致伤后各组均出现范围和程度不同的肺间质出血、肺泡出血、肺泡水肿和小叶性肺炎。尿酸组和急性肺损伤组相比 ,病变程度较轻。结论 :尿酸能减轻油酸引起的肺损伤 ,是氧自由基清除剂 ,可间接地证明氧自由基在急性肺损伤中有一定的作用     

肠缺血再灌注时肺泡Ⅱ型上皮细胞凋亡与肺损伤

目的 观察肠缺血再灌注中肺损伤与肺泡Ⅱ型上皮细胞凋亡的关系及其可能的发生机制。方法 Wistar大鼠,肠系膜上动脉夹闭后松夹造成肠缺血再灌注。不同时间点活杀动物,测肺通透指数、肺泡灌洗液（BALF）和血浆中NO、IL-2含量,分离肺泡Ⅱ型上皮细胞,观察凋亡率。结果与结论 肠缺血再灌注可能引起肺损伤;肠缺血再灌注后肺泡Ⅱ型上皮细胞凋亡率上升,再灌注30 min 达高峰;缺血再灌注后血、BALF中NO、IL-2增加;肺泡Ⅱ型上皮细胞凋亡率与肺通透指数显著相关,BALF中IL-2水平与肺通透指数、肺泡Ⅱ型上皮细胞凋亡率显著相关。