家兔海水型呼吸窘迫综合征肺损伤及其机制研究

本文对海水型呼吸窘迫综合征（ＳＷ－ＲＤＳ）兔肺酶活性变化、肺磷脂和Ｃａ＾２＋的分布及肺细胞膜损伤程度进行了分析研究。结果发现，ＳＷ－ＲＤＳ模型组兔ＰａＯ２进行性下降。肺毛细血管内皮细胞、肺泡Ⅰ、Ⅱ型上皮细胞在超微结构上有明显损伤现象。其胞质内及肺泡Ⅱ型上皮细胞线粒体和板层体内有许多镧颗粒分布。肺泡Ⅱ型细胞板层小体和肺泡上皮细胞表面的磷脂含量明显减少，而肺毛细血管腔内磷脂含量却增高。肺Ⅰ、Ⅱ型细胞及     

牛磺酸对大鼠肢体缺血再灌注后肺损伤时细胞凋亡的影响

目的:从细胞凋亡的角度探讨肢体缺血再灌注(LIR)后急性肺损伤(ALI)的发病机制及牛磺酸的影响。方法:复制大鼠肢体缺血再灌注(LIR)损伤动物模型,采用TUNEL法、电泳法、半定量逆转录聚合酶链反应(SqRT-PCR)及免疫组织化学等技术观察LIR后肺损伤发生过程中,肺泡上皮及血管内皮细胞凋亡变化以及Fas/FasL系统蛋白质和mRNA表达的改变。结果:大鼠LIR后,肺泡上皮细胞和肺血管内皮细胞凋亡明显增加;肺组织Fas/FasLmRNA和蛋白质表达明显上调,DNA断链率、组织钙含量和活性氧(ROS)升高,且与肺泡上皮及血管内皮细胞凋亡的增加相一致。结论:肺泡上皮及血管内皮细胞凋亡以及Fas/FasL系统表达明显上调可能参与LIR后ALI的发生;牛磺酸可减少肺组织细胞凋亡,但并非通过影响Fas/FasL基因表达而实现其保护效应。     

IL-10抗内毒素气管内滴注致急性肺损伤作用的实验研究关

目的:探讨中性粒细胞(PMN)在急性肺损伤(ALI)发生中的作用及IL-10对ALI的拮抗作用。方法: 用LPS(100 μg/只)或LPS+IL-10(1 μg/只)向SD大鼠气管内滴注复制ALI模型,检测支气管肺泡灌洗液(BALF)中PMN数目、蛋白质及丙二醛(MDA)含量,并进行组织学观察。结果: LPS气管内滴注可引起BALF中PMN数目明显增加,伴有蛋白质及MDA含量的增高,光镜观察显示肺组织间隙弥漫性炎细胞浸润。LPS+IL-10组则BALF中PMN数目、蛋白质及MDA含量显著低于LPS组,肺组织中PMN浸润程度也明显轻。结论: PMN在ALI发病中具有重要作用。IL-10能够拮抗LPS所致ALI的发生。     

高浓度氧对早产鼠肺发育影响的动态研究

目的为探讨高浓度氧对早产儿肺泡发育影响的动态变化规律.方法以暴露于高氧环境中早产鼠为研究对象,分别采用光镜和透色电镜技术,观察不同吸氧时间肺重量与体重比、肺组织形态学及Ⅱ型肺泡上皮细胞(AEC-Ⅱ)超微结构变化.结果 1)肺重量/体重:于吸氧7d和14d,实验组明显低于对照组(P<0.01);2)肺形态学:吸高氧7d即开始出现肺泡化障碍,14d肺泡体积明显增大、肺泡融合、数目减少,21d时正常的肺泡结构几乎消失;3)AEC-Ⅱ的超微结构:暴露高氧1d即出现线粒体(Mi)肿胀,3d板层小体(LB)开始排空,7d细胞核发生异常改变,14～21d,逐渐出现Mi嵴消失,LB空泡变性,细胞核溶解、固缩.结论吸入高浓度氧早期即可损伤AEC-Ⅱ,继之影响肺泡发育成熟,且随吸氧时间的延长,损伤逐渐加重.     

血红素氧合酶对大鼠肺缺血再灌注损伤的保护作用

探讨血红素氧合酶 1(HO 1)对大鼠肺缺血再灌注损伤 (I/R)的保护作用。Wistar大鼠随机分成假手术 (sham)组、I/R组、Hemin组和ZnPP IX组。采用夹闭大鼠左肺门 30min ,再灌注 12 0min ,分别观察各组HO 1活性 ,肺组织形态学变化 ,肺湿干重比、伊文思蓝含量、支气管肺泡灌洗液 (BALF)中细胞计数及蛋白含量变化。与sham组比较 ,I/R组和hemin组肺组织HO 1活性显著增高 (P <0 0 1) ,ZnPP IX组能取消hemin诱导的HO 1活性增高 (P <0 0 1)。光镜下可见I/R组和ZnPP IX组肺组织水肿 ,部分动物肺泡腔中可见出血 ,并伴有局部肺不张 ,而hemin组肺组织形态学改变明显减轻。Hemin组肺湿干重比、伊文思蓝含量、BALF中细胞数和蛋白含量均低于I/R组和ZnPP IX组 ,但仍高于sham组 (P <0 0 1)。结果提示 ,HO 1对在体大鼠肺I/R损伤具有部分保护作用     

人肺表面活性物质结合蛋白B的研究现状

人肺表面活性物质结合蛋白Ｂ（ＳＰ－Ｂ）为肺泡表面活性物质中的重要成份。具有生物活性的ＳＰ－Ｂ存在于肺泡Ⅱ上皮细胞、肺泡巨噬细胞和肺泡中，在体外ＳＰ－Ｂ与磷脂的复合物即具有肺表面活性物质的大部分生物活性，而在体内可增强肺的顺应性，人ＳＰ－Ｂ基因定位第２号染色体，其基因表达受多种因素调节。遗传性ＳＰ－Ｂ缺乏病例已见报道。     

内毒素致兔肝线粒体膜磷脂含量改变及阳离子A的拮抗效应

目的： 采用内毒素血症兔实验模型，研究肝线粒体膜磷脂含量的改变及阳离子A的拮抗效应。方法: 将48只日本大耳白兔随机分为正常对照组(Ⅰ组)、内毒素组(Ⅱ组)和阳离子A拮抗组(Ⅲ组)。3组同时进行相应处理后，分别在第3、7 h 测定各组肝线粒体膜中磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)、磷脂酰丝氨酸(PS)和磷脂酰肌醇(PI)的含量变化。结果: Ⅱ组中PC、PE、PS、PI含量在第 3 h、7 h 均低于Ⅰ组，差异极显著(P<0.01)；而Ⅲ组中4种磷脂的含量在第 3 h、7 h 又均高于Ⅱ组(P<0.05, P<0.01)。结论: 内毒素致使兔肝线粒体膜磷脂含量降低，而阳离子A一定程度上具有对内毒素的拮抗作用和对肝线粒体膜的保护效应。     

油酸性肺损伤修复过程中某些酶活性的变化

以油酸(0.1ml/kg体重)静脉注入形成大白鼠急性肺损伤模型。观察到注油酸后1天内肺重增加,镜检可见水肿及白细胞在肺间质浸润。支气管肺泡冲洗液(BALF)中蛋白质含量及弹性蛋白酶(ELS)、α-抗胰蛋白酶(α_1-AT)、β-葡萄糖醛酸酶(β-g)活性均明显增高。之后以上变化逐渐减轻。至注油酸后7天,肺组织学检查几乎完全恢复正常,BALF中各指标也降至正常对照水平。提示油酸引起的急性肺损伤可以在较短时间内完全恢复。讨论了ELS和α_1-AT的平衡在损伤修复中的作用。同时提出了油酸除损伤肺脏外,对其它器官的损伤作用值得注意。     

败血症大鼠支气管肺泡灌洗液中磷脂含量及其与板层体关系的研究

在大鼠盲肠结扎加穿刺引起的败血症中发现支气管肺泡灌洗液中磷脂含量(较无败血症对照组)非常明显升高(P<0.001),肺系数明显升高(P<0.01)。败血症大鼠肺组织电镜观察发现肺泡Ⅱ型上皮细胞内板层体排空。作者认为,这是败血症早期由应激反应引起的一种代偿。     

目前我国对肺表面活性物质研究状况

肺表面活性物质(Pulmonary Surfactant)简称PS,是由肺泡Ⅱ型细胞合成和分泌的一种脂蛋白复合物,其主要成份是饱和卵磷脂,在肺泡气液界面上形成单分子膜.具有降低肺泡表面张力、稳定肺泡、减少呼吸功、维持正常肺功能等重要作用.国外对PS引起关注,并从事有关的研究是从50年代开始的.30多年来,对PS系统的组成、形态结构,化学成份、代谢过程、物理化学特征、生理功能、合成与分泌的调节、以及PS与各种呼吸疾病的关系等各方面作了深入的研究.特别是1980年Fujiware等人用从牛肺中提取的PS,经气管给10名肺透明膜患儿滴注治疗,患儿血氧发生明显改善.Fujiware等人这一研究工作的成功极大地鼓舞人们.这为PS用于临床闯出了一条新路.很快各国均报道     

DADLE对大鼠急性全脑缺血再灌注继发肺损伤的作用

 目的：通过建立大鼠急性全脑缺血再灌注模型,观察肺组织超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量及肺组织光镜、电镜病理变化,探讨δ阿片受体激动剂DADLE对急性肺损伤的保护作用。方法：SD大鼠30只随机分为假手术（sham）组、模型（I/R）组和DADLE处理组。采用改良的二血管阻断加低血压法建立全脑缺血再灌注模型。DADLE处理组（n=10）于再灌注前经左侧颈静脉注射DADLE 5 mg/kg,再灌注120 min后,取肺组织,光镜、电镜观察其病理学改变及检测肺组织SOD活性、MDA含量。右侧股动脉取血测定氧分压,计算氧合指数。结果：I/R组与 sham组比较,肺脏表现为肺泡间隔增宽,毛细血管扩张充血,肺胞腔内及血管周围中性粒细胞浸润,Ⅱ型上皮细胞表面微绒毛明显减少,肺胞腔及气管腔均有浆液渗出,大鼠肺组织SOD活性降低和MDA含量升高。DADLE处理组与I/R组比较肺脏充血减轻,肺组织损伤程度明显减轻,中性粒细胞浸润有所减少,SOD活性升高和MDA含量降低。DADLE处理组动脉血氧分压和氧合指数有升高趋势,与I/R组比较差异有统计学意义。结论：大鼠急性全脑缺血再灌注模型对肺有不同程度的损伤,DADLE可减轻急性肺损伤,对肺组织提供一定的保护作用。     

Effect of pattern of breathing on subfractions of surfactant in tissue and alveolar compartments of the adult rat lung

We have used tow previously characterized models of hyperpnea in vivo and different modes of ventilation in the isolated perfused rat lung to investigate changes in the phospholipid content of tubular myelin-rich (PLalv-1) and -poor (PLalv-2) fractions isolated from lavaged material and of two lamellar body subfractions. A vesicular lamellar body subfraction (lbB) was preferentially released during 30-min swimming. However, during the subsequent 3-h recovery period there was a preferential supplementation of the classic-appearing lamellar body fraction (lbA). Hyperpnea induced by exposure to 5% CO2/13% O2/82% N2 led to an increase in lbA after 12 h and in lbB after 48 h. Whereas PLalv-2 was elevated above control values after 8 h, PLalv-1 remained unchanged until 24 h. In the perfused lung isolated from rats infused with [methyl-3H]choline chloride 3 h previously, salbutamol, a deep breath, and increased tidal volume (VT) all increased total alveolar phospholipids; however, the pattern of change was very different. Salbutamol markedly elevated PLalv-1 and increased the specific activity of both alveolar fractions. In contrast, a single deep breath increased PLalv-2 while slightly increasing the specific activity of PLalv-1. Finally, an increased VT decreased PLalv-1 while inducing a large increase in PLalv-2; it increased specific activity in both alveolar fractions. Both salbutamol and an increased VT decreased phospholipids in lbA. We conclude that lbA and lbB vary in their response to different stimuli. In vivo, PLalv-1, the tubular myelin-rich fraction, remains very constant, a fact consistent with its being the controlled variable in surfactant homeostasis.(ABSTRACT TRUNCATED AT 250 WORDS)     

抑制mTOR信号通路对幼鼠肺损伤时p-AKT1分子的影响及意义

目的:探讨抑制哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号通路在高体积分数氧(高氧)致SD幼鼠肺损伤时对磷酸化AKT1(p-AKT1)分子的影响和意义。方法:72只SD幼鼠(3周龄)随机分为空气+生理盐水组、高氧+生理盐水组、高氧+OSI-027组及高氧+雷帕霉素组(n=18),分别构建动物模型。高氧选择90%氧气持续干预,生理盐水、OSI-027和雷帕霉素干预分别在观察期第1、3、6、8、10和13天时经腹腔注射给药。在造模第3、7和14天时取各组幼鼠进行体重测量、肺湿干重比(wet/drg weight ratio,W/D)计算、肺组织病理学检查、肺泡间隔宽度测定和肺损伤评分,肺组织免疫组化和Western blot检测磷酸化S6K1(p-S6K1)和p-AKT1的分布与水平。结果:与空气组比较,高氧组幼鼠体重明显下降(P0.05),肺损伤急性期肺W/D增高(P0.05),肺泡间隔宽度及肺损伤评分明显增加(P0.05),肺组织p-S6K1阳性细胞增多(P0.05),肺组织p-AKT1阳性细胞减少(P0.05),p-S6K1蛋白显著升高(P0.01),p-AKT1蛋白明显减低(P0.01);与高氧组比较,高氧+OSI-027组的肺组织损伤减轻,肺组织p-S6K1阳性细胞减少(P0.05),p-AKT1阳性细胞增多(P0.05),p-S6K1蛋白水平显著降低(P0.05),p-AKT1蛋白水平增加(P0.05);高氧+雷帕霉素组的肺损伤进一步加重(P0.05),p-S6K1阳性细胞减少(P0.05),p-AKT1阳性细胞增加(P0.05),p-S6K1蛋白水平显著降低(P0.05),p-AKT1蛋白水平显著增加(P0.05)。与高氧+雷帕霉素组比较,高氧+OSI-027组的肺组织损伤减轻(P0.05),肺组织p-AKT1阳性细胞减少(P0.05),p-AKT1蛋白水平降低(P0.05)。结论:p-AKT1参与了高氧肺损伤的发生发展,其调控机制可能与抑制mTOR信号通路的活化有关。高氧肺损伤时,p-AKT1蛋白水平下降,mTOR抑制剂能增加p-AKT1蛋白水平,但只有mTORC1/2双重抑制剂OSI-027能减轻高氧所致SD幼鼠的肺损伤及纤维化。     

Alveolar type II cell abnormalities and peroxide formation in lungs of rats given IL-1 intratracheally

Acute lung injury (ALI) is characterized by increased lung levels of proinflammatory cytokines, inflammation, oxidative stress, edema, and impaired gas exchange. Notably, ALI patients also exhibit pulmonary surfactant abnormalities, including increased levels of phospholipids in their lung lavages. In the present study, to assess early alterations of the lung surfactant system in ALI, we induced inflammation and acute lung injury in rats by administering interleukin-1 (IL-1) intratracheally. Five h after IL-1 instillation, we examined lung tissue ultrastructure by electron microscopy using both routine staining methods and cerium chloride staining to localize hydrogen peroxide (H₂O₂) histologically. We also measured lung lavage phospholipid levels, lung tissue -glutamyl transpeptidase (GGT) activities (a marker of oxidative stress), and arterial blood oxygen tensions. We observed that lungs of rats given IL-1 intratracheally had increased neutrophil accumulation, increased H₂O₂ production, and increased alveolar type II (ATII) pneumocyte ultrastructural abnormalities compared to rats given saline intratracheally. Intratracheal instillation of IL-1 also increased phospholipid levels in the bronchoalveolar lavage (BAL), possibly as a consequence of the abnormal discharge of lamellar bodies into the alveolar lumen. In addition, IL-1-insufflated rats had increased lung GGT levels and impaired blood oxygenation compared to saline-insufflated rats. Treatment with mepacrine decreased lung neutrophil accumulation, ultrastructural lung abnormalities, lung lavage phospholipid levels, lung tissue GGT levels, and blood oxygenation impairment in rats given IL-1 intratracheally, suggesting a possible relationship between these events. Our results indicate that IL-1-induced acute lung injury in rats is marked by neutrophil-dependent oxidative stress, ATII cell defects, abnormal discharge of lamellar body phospholipids, and impaired blood oxygenation.     

The 150-kilodalton oxygen-regulated protein ameliorates lipopolysaccharide-induced acute lung injury in mice

The 150-kd oxygen-regulated protein is a novel stress protein that is located in the endoplasmic reticulum and contributes to cell survival when this organelle is under stress. Expression of this protein was strongly increased in alveolar macrophages and alveolar epithelial cells from mice with acute lung injury induced by lipopolysaccharide. Transgenic mice overexpressing the 150-kd protein showed decreased histological severity of this lung injury, accompanied by lower total protein concentrations, and lactate dehydrogenase activity in bronchoalveolar lavage fluid. As indicated by nick end-labeling, lipopolysaccharide induced apoptosis in fewer alveolar wall cells in transgenic than in wild-type mice. Transgenic mice also showed increased survival after lipopolysaccharide injection (a log-rank test). Thus, the 150-kd protein, an endoplasmic reticulum-related molecular chaperone, is pivotal in resisting acute lung injury from lipopolysaccharide.     

胍丁胺对内毒素诱导的大鼠急性肺损伤的治疗效果

目的：研究胍丁胺对内毒素（ LPS）诱导的急性肺损伤治疗效果及其机制。方法：采用LPS 诱导大鼠急性 肺损伤模型并予以胍丁胺治疗,分为对照组,单纯模型组,低、高剂量胍丁胺治疗组。绘制Kaplan-Meier 生存曲 线观察胍丁胺治疗后大鼠生存率差异,并检测肺组织湿干比及组织炎症情况;检测肺组织中抗氧化酶（SOD）活性、 丙二醛（ MDA）含量;收集肺泡灌洗液并提取肺组织总蛋白,检测肺组织及肺泡灌洗液中炎症因子白细胞介素6 （ IL-6）、肿瘤坏死因子α（ TNF-α）含量。结果：胍丁胺可提高LPS 诱导的大鼠急性肺损伤模型的生存率、显著 降低肺组织的湿重/ 干重比。H-E 染色结果显示胍丁胺可改善肺组织炎症状况。与单纯模型组相比,低、高剂量 胍丁胺治疗组的肺组织MDA 含量下降、SOD活性上调,差异具有统计学意义。ELISA 结果表明,低、高剂量胍 丁胺治疗组的肺组织及肺泡灌洗液中IL-6、TNF-α 分泌降低。结论：胍丁胺可抑制肺部过度氧化应激及炎症反应, 发挥对急性肺损伤的保护作用。     

骨髓间充质干细胞移植治疗重症急性胰腺炎肺损伤

BACKGROUND:A large number of studies have confirmed that bone marrow mesenchymal stem cells can couple with the circulation of the blood to other organs, promote pancreatic tissue repair injury and reduce pulmonary fibrosis, which have certain therapeutic effects on pancreas and lung injuries. OBJECTIVE:To study the therapeutic effect on severe acute pancreatitis-associated lung injury in rats after the transplantation of bone marrow mesenchymal stem cells. METHODS:Animal models of severe acute pancreatitis-associated lung injury were prepared in rats via retrograde injection of 4% sodium taurocholate. Sprague-Dawley rats were randomized into three groups and received bone marrow mesencnymal stem cell injection via the tail vein in transplantation group, the same volume of normal saline in control group, or no treatment in normal groups. All the treatments in each group were performed 24 hours after modeling. Twenty-four hours after transplantation, hematoxylin-eosin staining of the pancreatic and lung tissues was performed. mRNA expressions of tumor necrosis factor-α and interleukin-1β in pancreatic and lung tissues were detected. ELISA kit was used to detect levels of serum C-reactive protein and tumor necrosis factor-α. RESULTS AND CONCLUSION:After modeling, under hematoxylin-eosin staining, there were a large number of inflammatory cells infiltrating in the damaged pancreatic tissues, accompanied by incomplete acinar structures, seriously destroyed lobular structures, alveolar fusion in the lung tissues, thickening of the alveolar walls, and a large amount of inflammatory cells infiltrating in the alveoli. These findings indicated successful modeling of severe acute pancreatitis-associated lung injury in rats. After cell transplantation, the number of infiltrated inflammatory cells in the damaged pancreatic tissue was reduced, with clear lobular structures and no bleeding from the acini; the structure of lung tissues was clear, with complete alveolar walls, and the width of alveolar space was reduced. Immunohistochemical results showed that transplanted DAPI-labeled bone marrow mesenchymal stem cells were aggregated in the pancreas and lung tissue, and uneven distributed in the damaged area. No DAPI expression in the pancreas and lung tissue was found in the control group, indicating transplanted bone marrow mesenchymal stem cells migrated into the damaged pancreas and lung tissue through the blood circulation, to further repair the damage area. RT-PCR test results showed that compared with the control group, bone marrow mesenchymal stem cell transplantation significantly reduced the levels of tumor necrosis factor-α and interleukin-1β in the pancreatic and lung tissues (P < 0.05). Higher levels of C-reactive protein and tumor necrosis factor-α were found in the control group compared with the normal group (P < 0.01), while the lower levels were obtained in the control group (P < 0.05). To conclude, our findings suggest that bone marrow mesenchymal stem cell transplantation is an effective therapy for severe acute pancreatitis-associated lung injury, and its mechanism may be associated with the reduction of inflammatory reactions and translation into the pancreas and lung tissue.     

Double intratracheal instillation of keratinocyte growth factor prevents bleomycin-induced lung fibrosis in rats

Alveolar re-epithelialization is necessary in the repair of damaged alveolar epithelium after lung injury. Keratinocyte growth factor (KGF) has been shown to be a potent proliferation and differentiation factor for rat alveolar type II cells. The present study examined whether KGF would prevent bleomycin-induced lung fibrosis. Adult rats were anaesthetized and recombinant human KGF (rhKGF) (150 μg/kg) or saline was injected intratracheally at 48 h before and 24 h after bleomycin (Bleo, 5 mg/kg) instillation. Seven and 14 days after the last administration, rat lungs were processed for lung physiology, immunohistochemistry, and in situhybridization. Double instillation of KGF prevented the loss of body weight and reduction in total lung capacity (TLC) due to Bleo, and markedly attenuated the protein accumulation and mRNA expression of collagen types I and III and the decreased expression of surfactant protein mRNAs in the fibrotic lesions of Bleo-treated rats. KGF may play an important role in maintaining alveolar epithelium and repairing the damaged epithelium after lung injury. © 1998 John Wiley & Sons, Ltd.     

低分子肝素联合乌司他丁治疗急性百草枯中毒大鼠肺纤维化的实验研究

目的探讨低分子肝素联合乌司他丁减轻急性百草枯（PQ）中毒大鼠肺纤维化的可能作用机制。方法55只雄性SD大鼠,随机分成正常对照组（A组）、模型组（B组）、治疗组（C组）;B、C组禁食1h后经口一次灌胃百草枯75mg／kg制作PQ大鼠肺纤维化模型,A组经口一次性注人等量生理盐水;c组造模后皮下注射低分子肝素钠1000U／d,同时腹腔注射乌司他丁10万U,共14d,A、B组给予0．2ml／d生理盐水皮下注射。分别于造模后1、3、7、14、28d测定血清转化生长因子β1（TGFβ1）、基质金属蛋白酶9（MMP-9）含量;并取肺组织做HE染色。结果与A组比较,B组血清TGF-β1第3天始明显升高（P〈0．01）,血清MMP-9于第7天逐渐上升（P〈0．05）,第28天明显升高（P〈0．01）;与B组各相同时间点比较,C组MMP-9水平下降,至第7天差异有统计学意义（P〈0．05）,第28天出现明显下降（P〈0．01）;而血清TGF．131在第14天开始出现明显下降（P〈0．01）。B组于造模后早期即出现肺泡壁增厚,炎症细胞浸润明显,毛细血管充血、水肿等,14d肉眼可见肺表面溃疡形成,镜下可见肺泡间隔成纤维母细胞、肌纤维细胞增生,肺泡塌陷;C组于14d时镜下可见有肺泡壁毛细血管充血,炎性细胞浸润较B组轻,肺纤维化程度也有所减轻。结论低分子肝素联合乌司他丁可减少MMP-9的合成,从而减轻大鼠纤维化程度,其途径可能通过减少TGF．Bl的合成。