This work was supported by NIH HL-10342

注:所有动物方案批准了约翰·霍普金斯大学动物护理和使用委员会。 1.动物准备<ol><li>制备6的C57BL / 6对照小鼠为DFCO测定，通过如以下步骤2.3中概述用氯胺酮和赛拉嗪麻醉它们。 </li><li>通过使用相同的程序作为用于控制准备的所有其他小鼠在表1所示的不同的肺病理学。建立这些模型需要的具体细节中找到相关的文献。对照小鼠和那些在其他病理队列都是6-12周龄。 </li></ol> 2.测量扩散系数一氧化碳（DFCO） <ol><li>建立与机器供给至测量为氮，氧，氖，和一氧化碳峰的气相色谱仪模块。对于这个应用程序只使用霓虹灯和CO的数据。 注:本仪器采用分子sieve柱以氦作为载气，用12.00微米膜，320.00微米ID和10米长。色谱仪柱具有0.8毫升的体积，但我们用来2毫升确保连接管与样品的充分清除。 </li><li>在每个实验日的开始之前，使得从小鼠的样品的测量结果，取2ml样品直接从含有大约0.5％的氖，0.5％的CO的气体混合物包，和平衡空气，并且使用该样本来校准气相色谱仪。 </li><li>麻醉小鼠用氯胺酮（90毫克/千克）和赛拉嗪（15毫克/千克），并由于没有反射运动的确认麻醉。取适量涂抹于眼睛兽医药膏，以防止干燥。 Tracheostomize的小鼠存根针管（18克成人或20G的非常年轻小鼠）。 注:DFCO完成在麻醉后不到10分钟，并优先于任何机械通风或其他程序。 </li><li>在小鼠中大于6周龄，使用3毫升注射器吨ø撤回0.8毫升气体从气体混合物包。注射器连接到气管插管，迅速膨胀的肺。使用节拍器，算上9秒，然后迅速撤回0.8毫升（呼出的空气）。 </li><li>淡化这种撤回0.8毫升呼出的空气〜2毫升室内空气，让它休息至少15秒。然后注入整个样品注入气相色谱仪进行分析。 </li><li>在分析该第一DFCO样品，膨胀的小鼠肺与第二0.8毫升从气体混合物包，然后处理该样品与第一样品。平均两个DFCO测量。 注:有关小鼠年仅2周龄时测量，用0.4毫升的体积，因为0.8毫升过大的体积，使测量非常年轻小鼠的肺部。最好是使用0.8毫升体积超过6周小鼠，而且如果是需要一些小鼠0.4毫升体积，应当一致地用于正在研究中的队列的所有小鼠。 </li><li>计算DFCO如1 - （CO 9 / CO C）/（氖9 /氖c）中 ，其中c和9标是指注入的校准气体的浓度，并分别经过9秒屏气时间除去气体。 </li><li>分析和比较用单向ANOVA差异和评估与Tukey的校正中的所有队列小鼠多重比较的显着性水平。考虑P &lt;0.05为显著的价值。 注意:所有在这里所用的小鼠是涉及肺通气，力学，肺灌洗，或组织学的几个后续测量，这未在此处报道的实验研究的一部分。此外，由于该方法是在所有的实验模型如在对照小鼠上面做了同样的，只能从各种病理模型的结果。这些模型的进一步信息呈现在补充表。 </li><li>安乐死的动物深anesthe抽动过量颈椎脱位或斩首。在需要的地方，从死老鼠进一步生物或组织学处理和分析取出肺细胞和/或组织。 </li></ol>

<ol>
	<li>Ogilvie, C. M., Forster, R. E., Blakemore, W. S., Morton, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+standardized+breath+holding+technique+for+the+clinical+measurement+of+the+diffusing+capacity+of+the+lung+for+carbon+monoxide.">A standardized breath holding technique for the clinical measurement of the diffusing capacity of the lung for carbon monoxide.</a> J Clin Invest. 36 (1 Pt 1), 1-17 (1957).</li><li>Miller, A., Warshaw, R., Nezamis, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusing+capacity+and+forced+vital+capacity+in+5,003+asbestos-exposed+workers:+Relationships+to+interstitial+fibrosis+(ILO+profusion+score)+and+pleural+thickening.">Diffusing capacity and forced vital capacity in 5,003 asbestos-exposed workers: Relationships to interstitial fibrosis (ILO profusion score) and pleural thickening.</a> Am J Ind Med. 56 (12), 1383-1393 (2013).</li><li>Enelow, R. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+and+functional+consequences+of+alveolar+cell+recognition+by+CD8(+)+T+lymphocytes+in+experimental+lung+disease.">Structural and functional consequences of alveolar cell recognition by CD8(+) T lymphocytes in experimental lung disease.</a> J Clin Invest. 102 (9), 1653-1661 (1998).</li><li>Hartsfield, C. L., Lipke, D., Lai, Y. L., Cohen, D. A., Gillespie, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+mechanical+and+immunologic+dysfunction+in+a+murine+model+of+AIDS.">Pulmonary mechanical and immunologic dysfunction in a murine model of AIDS.</a> Am J Physiol. 272 (4 Pt 1), 699-706 (1997).</li><li>Wegner, C. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intercellular+adhesion+molecule-1+contributes+to+pulmonary+oxygen+toxicity+in+mice:+role+of+leukocytes+revised.">Intercellular adhesion molecule-1 contributes to pulmonary oxygen toxicity in mice: role of leukocytes revised.</a> Lung. 170 (5), 267-279 (1992).</li><li>Reinhard, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inbred+strain+variation+in+lung+function.">Inbred strain variation in lung function.</a> Mamm Genome. 13 (8), 429-437 (2002).</li><li>Sabo, J. P., Kimmel, E. C., Diamond, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+the+Clara+cell+toxin,+4-ipomeanol,+on+pulmonary+function+in+rats.">Effects of the Clara cell toxin, 4-ipomeanol, on pulmonary function in rats.</a> J Appl Physiol. 54 (2), 337-344 (1983).</li><li>Depledge, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Respiration+and+lung+function+in+the+mouse,+Mus+musculus+(with+a+note+on+mass+exponents+and+respiratory+variables).">Respiration and lung function in the mouse, Mus musculus (with a note on mass exponents and respiratory variables).</a> Respir Physiol. 60 (1), 83-94 (1985).</li><li>Depledge, M. H., Collis, C. H., Barrett, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+technique+for+measuring+carbon+monoxide+uptake+in+mice.">A technique for measuring carbon monoxide uptake in mice.</a> Int J Radiat Oncol Biol Phys. 7 (4), 485-489 (1981).</li><li>Fallica, J., Das, S., Horton, M. R., Mitzner, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+Carbon+Monoxide+Diffusing+Capacity+in+the+Mouse+Lung.">Application of Carbon Monoxide Diffusing Capacity in the Mouse Lung.</a> J Appl Physiol. 110 (5), 1455-1459 (2011).</li><li>Chaudhary, N., Datta, K., Askin, F. B., Staab, J. F., Marr, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cystic+fibrosis+transmembrane+conductance+regulator+regulates+epithelial+cell+response+to+Aspergillus+and+resultant+pulmonary+inflammation.">Cystic fibrosis transmembrane conductance regulator regulates epithelial cell response to Aspergillus and resultant pulmonary inflammation.</a> Am J Respir Crit Care Med. 185 (3), 301-310 (2012).</li><li>Foster, W. M., Walters, D. M., Longphre, M., Macri, K., Miller, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methodology+for+the+measurement+of+mucociliary+function+in+the+mouse+by+scintigraphy.">Methodology for the measurement of mucociliary function in the mouse by scintigraphy.</a> J Appl Physiol. 90 (3), 1111-1117 (2001).</li><li>Yildirim, A. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Palifermin+induces+alveolar+maintenance+programs+in+emphysematous+mice.">Palifermin induces alveolar maintenance programs in emphysematous mice.</a> Am J Respir Crit Care Med. 181 (7), 705-717 (2010).</li><li>Collins, S. L., Chan-Li, Y., Hallowell, R. W., Powell, J. D., Horton, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+vaccination+as+a+novel+treatment+for+lung+fibrosis.">Pulmonary vaccination as a novel treatment for lung fibrosis.</a> PLoS One. 7 (2), e31299 (2012).</li><li>Alessio, F. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD4+CD25+Foxp3++Tregs+resolve+experimental+lung+injury+in+mice+and+are+present+in+humans+with+acute+lung+injury.">CD4+CD25+Foxp3+ Tregs resolve experimental lung injury in mice and are present in humans with acute lung injury.</a> J Clin Invest. 119 (10), 2898-2913 (2009).</li><li>Martinez, F. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+clinical+course+of+patients+with+idiopathic+pulmonary+fibrosis.">The clinical course of patients with idiopathic pulmonary fibrosis.</a> Ann Intern Med. 142 (12 Pt 1), 963-967 (2005).</li><li>Zhou, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Correction+of+lethal+intestinal+defect+in+a+mouse+model+of+cystic+fibrosis+by+human+CFTR.">Correction of lethal intestinal defect in a mouse model of cystic fibrosis by human CFTR.</a> Science. 266 (5191), 1705-1708 (1994).</li></ol>

的兴趣，并没有什么不冲突透露。

在目前的工作中，我们定义了一个新的指标来量化小鼠肺的气体交换能力。这个度量类似于扩散能力，临床上常见的测量，其测量肺的主要功能，也就是它的交换气体的能力。扩散能力是唯一的肺功能测量，可以在小鼠和人类可容易且快速地进行。对于肺部疾病的小鼠的检测中，一个主要的目的是量化控制和实验队列之间肺功能的变化。为了实现这一目标，我们已经定义和使用的DFCO展示quanitfying?...

鼠标是目前用于模拟各种肺部疾病的主要动物。研究认为underly这样的病理机制，可以量化它的病理改变是需要的表型的方法。虽然有许多小鼠研究，其中通风力学测量，这些测量通常是无关的肺功能的标准评估在人类正常完成。这是不幸的，因为要执行在小鼠和人类受试者等效测量可以便于结果的翻译在小鼠模型与人类疾病的能力。 一种在人受试者中最常见的，并很容易地进行的测量的是一氧化碳（弥散）1,2-扩散能力，但是这种测量只有很少在小鼠模型中进行。在那些已经报道3-7的研究，没有出现过的后续研究中，部分是因为程序往往笨重，或者可以REQuire复杂的设备。另一种方法是在稳定状态下的系统，其具有能够测量CO扩散在有意识的小鼠的优点使用CO再呼吸方法。然而，这种方法非常麻烦，而且结果可以用鼠标的通风的水平以及O 2和CO 2浓度的8,9而改变。这些困难似乎已经排除了常规使用弥散量来检测小鼠肺病理学的，尽管它的几个优点。 规避问题漫射小鼠容量的测定中，一个简单的装置的细节，以测量它在小鼠中最近已报道10。该过程消除了快速采样体积等于整个灵感气体采样未被污染的肺泡气难的问题。这个过程的结果在一个非常可重复的测量，称为扩散系数为一氧化碳（DFCO），即到主机PA的敏感thologic变化在肺表型。因此DFCO计算为1 - （CO 9 / CO C）/（氖9 /氖c）中 ，其中c和9标是指注入的校准气体的浓度和后9秒屏气时间除去气体，分别。 DFCO是无量纲变量，0和1之间变化，其中1反映所有的CO完全吸收，而0反映无吸收的CO。 在这份报告中，我们展示了如何让这个弥散量的测量，以及如何可以用来记录变化，几乎所有现有的小鼠肺疾病模型，包括肺气肿，肝纤维化，急性肺损伤，以及病毒和真菌感染。

<table><tbody><tr><td>Gas Chromatograph</td><td>Inficon</td><td>Micro GC Model 3000A</td><td>Agilent makes a comparable model</td></tr><tr><td>18 G Luer stub needle</td><td>Becton Dickenson</td><td></td><td>Several other possible vendors</td></tr><tr><td>3 ml plastic syringe</td><td>Becton Dickenson</td><td></td><td>Several other possible vendors</td></tr><tr><td>Polypropylene gas sample bags</td><td>SKC</td><td>1 or 2 L capacity works well</td><td>Other gas tight bags will work well</td></tr><tr><td>Gas tank, 0.3% Ne, 0.3% CO, balance air; (size ME)</td><td>Airgas, Inc</td><td>Z04 NI785ME3012</td><td>This is the standard mixture used for DLCO in humans</td></tr><tr><td>25 TCID50/mouse of influenza virus A/PR8 diluted in phosphate buffered saline.</td><td></td><td></td><td></td></tr><tr><td>Porcine pancreatic elastase</td><td>Elastin Products, Owensville, MO</td><td></td><td>5.4 U</td></tr><tr><td>Bleomycin</td><td>APP Pharmaceuticals, Schaumburg, IL</td><td></td><td>0.25 U</td></tr><tr><td>&lt;em&gt;Escherichia coli&lt;/em&gt; LPS</td><td>Sigma L2880</td><td></td><td>3 &amp;mu;g/g body weight; O55:B5</td></tr><tr><td>&lt;i&gt;Aspergillus fumigatus &lt;/i&gt; (isolate Af293) conidia were collected from mature colonies grown on potato dextrose agar.</td><td></td><td></td><td></td></tr></tbody></table>

phenotyping mouse pulmonary function in vivo with the lung diffusing capacity

鼠标是目前用于模拟各种肺部疾病的主要动物。研究背后等病理机制，能够量化的病理改变是需要的表型的方法。此外，以提供平移的相关性的小鼠模型中，这样的测量应测试，可以很容易地在人类和小鼠中进行。不幸的是，在本文献中很少的表型肺功能的测量直接适用于人类。一个例外是对一氧化碳，这是一种测量被定期在人中进行的弥散能力。在本报告中，我们描述了快速，简单地衡量这种扩散能力的小鼠的一种手段。该过程涉及简要肺膨胀与示踪气体麻醉小鼠，接着是1分钟的气体分析时间。我们已经测试了该方法的检测几个肺病理学，包括肺气肿，纤维化，急性肺损伤，和流感和能力真菌肺部感​​染，以及在年轻幼仔监测肺成熟。结果表明在所有的肺病理学显著下跌，以及增加漫射容量与肺成熟。肺弥散量这一测量从而提供了一个肺功能测试有其检测与大多数现有的病理肺模型的表型的结构性变化的能力具有广阔的应用。

图1示出了从成年小鼠在组A，B，C，D，E和F的DFCO测量有显著下跌同时与曲霉属和流行性感冒感染，以及在纤维化，气肿显著减少，急性肺损伤的模型。 图2示出在DFCO随时间小鼠年龄2-6周的G组的发展变化。有轻微但显著增加与肺发育超过这个时间过程。使用较小的膨胀体积的效果也是在6周的时间点相当明显。有对女性具有稍高DFCO的倾向，但是这只是在5周时间点显著。 ...

Watch this Scientific Journal Video about Phenotyping Mouse Pulmonary Function In Vivo with the Lung Diffusing Capacity at JoVE.com

Phenotyping Mouse Pulmonary Function In Vivo with the Lung Diffusing Capacity

We describe a means to quickly and simply measure the lung diffusing capacity in mice and show that it is sufficiently sensitive to phenotype changes in multiple common lung pathologies. This metric thus brings direct translational relevance to the mouse models, since diffusing capacity is also easily measured in humans.

表型鼠标肺功能<em&gt;在体内</em&gt;与肺弥散功能

The mouse is now the primary animal used to model a variety of lung diseases. To study the mechanisms that underlie such pathologies, phenotypic methods ...

phenotyping-mouse-pulmonary-function-vivo-with-lung-diffusing

Research

JoVE Journal

Biology

Phenotyping Mouse Pulmonary Function In Vivo with the Lung Diffusing Capacity

10.6K 次观看.  Johns Hopkins University Bloomberg School of Public Health. We describe a means to quickly and simply measure the lung diffusing capacity in mice and show that it is sufficiently sensitive to phenotype changes in multiple common lung pathologies. This metric thus brings direct translational relevance to the mouse models, since diffusing capacity is also easily measured in humans.

视频: Phenotyping Mouse Pulmonary Function In Vivo with the Lung Diffusing Capacity

Automated Measurement of Pulmonary Emphysema and Small Airway Remodeling in Cigarette Smoke-exposed Mice

COPD is projected to be the third most common cause of mortality world-wide by 2020(1). Animal models of COPD are used to identify molecules that contribute to the disease process and to test the efficacy of novel therapies for COPD. Researchers use a number of models of COPD employing different species including rodents, guinea-pigs, rabbits, and dogs(2). However, the most widely-used model is that in which mice are exposed to cigarette smoke. Mice are an especially useful species in which to model COPD because their genome can readily be manipulated to generate animals that are either deficient in, or over-express individual proteins. Studies of gene-targeted mice that have been exposed to cigarette smoke have provided valuable information about the contributions of individual molecules to different lung pathologies in COPD(3-5). Most studies have focused on pathways involved in emphysema development which contributes to the airflow obstruction that is characteristic of COPD. However, small airway fibrosis also contributes significantly to airflow obstruction in human COPD patients(6), but much less is known about the pathogenesis of this lesion in smoke-exposed animals. To address this knowledge gap, this protocol quantifies both emphysema development and small airway fibrosis in smoke-exposed mice. This protocol exposes mice to CS using a whole-body exposure technique, then measures respiratory mechanics in the mice, inflates the lungs of mice to a standard pressure, and fixes the lungs in formalin. The researcher then stains the lung sections with either Gill&#8217;s stain to measure the mean alveolar chord length (as a readout of emphysema severity) or Masson&#8217;s trichrome stain to measure deposition of extracellular matrix (ECM) proteins around small airways (as a readout of small airway fibrosis). Studies of the effects of molecular pathways on both of these lung pathologies will lead to a better understanding of the pathogenesis of COPD.

The goal of this protocol is to provide automated methods to quantify chronic lung pathologies in a murine model of COPD. The protocol includes exposing mice to cigarette smoke (CS), measuring pulmonary function, inflating the lungs, and using morphometry methods to measure emphysema and small airway remodeling in mice.

肺气肿，小气道重塑的香烟烟雾暴露小鼠自动测量

COPD is projected to be the third most common cause of mortality world-wide by 2020(1).  Animal models of COPD are used to identify molecules that ...

科研

医学

Measurement of the Pressure-volume Curve in Mouse Lungs

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential phenotypic changes are best assessed by measurement of the changes in lung elasticity. To best understand specific mechanisms underlying such pathologies in mice, it is essential to make functional measurements that can reflect the developing pathology. Although there are many ways to measure elasticity, the classical method is that of the total lung pressure-volume (PV) curve done over the whole range of lung volumes. This measurement has been made on adult lungs from nearly all mammalian species dating back almost 100 years, and such PV curves also played a major role in the discovery and understanding of the function of pulmonary surfactant in fetal lung development. Unfortunately, such total PV curves have not been widely reported in the mouse, despite the fact that they can provide useful information on the macroscopic effects of structural changes in the lung. Although partial PV curves measuring just the changes in lung volume are sometimes reported, without a measure of absolute volume, the nonlinear nature of the total PV curve makes these partial ones very difficult to interpret. In the present study, we describe a standardized way to measure the total PV curve. We have then tested the ability of these curves to detect changes in mouse lung structure in two common lung pathologies, emphysema and fibrosis. Results showed significant changes in several variables consistent with expected structural changes with these pathologies. This measurement of the lung PV curve in mice thus provides a straightforward means to monitor the progression of the pathophysiologic changes over time and the potential effect of therapeutic procedures.

Here we present a protocol to simply and reliably measure the lung pressure-volume curve in mice, showing that it is sufficiently sensitive to detect phenotypic parenchymal changes in two common lung pathologies, pulmonary fibrosis and emphysema. This metric provides a means to quantify the lung&#8217;s structural changes with developing pathology.

在小鼠肺压力容积曲线的测量

In recent decades the mouse has become the primary animal model of a variety of lung diseases. In models of emphysema or fibrosis, the essential ...

Intraperitoneal Glucose Tolerance Test, Measurement of Lung Function, and Fixation of the Lung to Study the Impact of Obesity and Impaired Metabolism on Pulmonary Outcomes

Obesity and respiratory disorders are major health problems. Obesity is becoming an emerging epidemic with an expected number of over 1 billion obese individuals worldwide by 2030, thus representing a growing socioeconomic burden. Simultaneously, obesity-related comorbidities, including diabetes as well as heart and chronic lung diseases, are continuously on the rise. Although obesity has been associated with increased risk for asthma exacerbations, worsening of respiratory symptoms, and poor control, the functional role of obesity and perturbed metabolism in the pathogenesis of chronic lung disease is often underestimated, and underlying molecular mechanisms remain elusive. This article aims to present methods to assess the effect of obesity on metabolism, as well as lung structure and function. Here, we describe three techniques for mice studies: (1) assessment of intraperitoneal glucose tolerance (ipGTT) to analyze the effect of obesity on glucose metabolism; (2) measurement of airway resistance (Res) and respiratory system compliance (Cdyn) to analyze the effect of obesity on lung function; and (3) preparation and fixation of the lung for subsequent quantitative histological assessment. Obesity-related lung diseases are probably multifactorial, stemming from systemic inflammatory and metabolic dysregulation that potentially adversely influence lung function and the response to therapy. Therefore, a standardized methodology to study molecular mechanisms and the effect of novel treatments is essential.

The incidence of obesity is rising and increases the risk of chronic lung diseases. To establish the underlying mechanisms and preventive strategies, well-defined animal models are needed. Here, we provide three methods (glucose-tolerance-test, body plethysmography, and lung fixation) to study the effect of obesity on pulmonary outcomes in mice.

腹腔葡萄糖耐受试验、肺功能测定和肺固定研究肥胖和代谢障碍对肺部结局的影响

Obesity and respiratory disorders are major health problems. Obesity is becoming an emerging epidemic with an expected number of over 1 billion obese ...

免疫与感染

Generation of a Chronic Obstructive Pulmonary Disease Model in Mice by Repeated Ozone Exposure

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and lung parenchymal destruction. It has a very high incidence in aging populations. The current conventional therapies for COPD focus mainly on symptom-modifying drugs; thus, the development of new therapies is urgently needed. Qualified animal models of COPD could help to characterize the underlying mechanisms and can be used for new drug screening. Current COPD models, such as lipopolysaccharide (LPS) or the porcine pancreatic elastase (PPE)-induced emphysema model, generate COPD-like lesions in the lungs and airways but do not otherwise resemble the pathogenesis of human COPD. A cigarette smoke (CS)-induced model remains one of the most popular because it not only simulates COPD-like lesions in the respiratory system, but it is also based on one of the main hazardous materials that causes COPD in humans. However, the time-consuming and labor-intensive aspects of the CS-induced model dramatically limit its application in new drug screening. In this study, we successfully generated a new COPD model by exposing mice to high levels of ozone. This model demonstrated the following: 1) decreased forced expiratory volume 25, 50, and 75/forced vital capacity (FEV25/FVC, FEV50/FVC, and FEV75/FVC), indicating the deterioration of lung function; 2) enlarged lung alveoli, with lung parenchymal destruction; 3) reduced fatigue time and distance; and 4) increased inflammation. Taken together, these data demonstrate that the ozone exposure (OE) model is a reliable animal model that is similar to humans because ozone overexposure is one of the etiological factors of COPD. Additionally, it only took 6 - 8 weeks, based on our previous work, to create an OE model, whereas it requires 3 - 12 months to induce the cigarette smoke model, indicating that the OE model might be a good choice for COPD research.

This study describes the successful generation of a new chronic obstructive pulmonary disease (COPD) animal model by repeatedly exposing mice to high concentrations of ozone.

反复臭氧暴露对小鼠慢性阻塞性肺疾病模型的产生

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and lung parenchymal destruction. It has a very high ...

Evaluation of Respiratory System Mechanics in Mice using the Forced Oscillation Technique

The forced oscillation technique (FOT) is a powerful, integrative and translational tool permitting the experimental assessment of lung function in mice in a comprehensive, detailed, precise and reproducible manner. It provides measurements of respiratory system mechanics through the analysis of pressure and volume signals acquired in reaction to predefined, small amplitude, oscillatory airflow waveforms, which are typically applied at the subject's airway opening. The present protocol details the steps required to adequately execute forced oscillation measurements in mice using a computer-controlled piston ventilator (flexiVent; SCIREQ Inc, Montreal, Qc, Canada). The description is divided into four parts: preparatory steps, mechanical ventilation, lung function measurements, and data analysis. It also includes details of how to assess airway responsiveness to inhaled methacholine in anesthetized mice, a common application of this technique which also extends to other outcomes and various lung pathologies. Measurements obtained in na&iuml;ve mice as well as from an oxidative-stress driven model of airway damage are presented to illustrate how this tool can contribute to a better characterization and understanding of studied physiological changes or disease models as well as to applications in new research areas.

The present protocol provides a detailed step-by-step description of the procedures required to execute measurements of respiratory system mechanics as well as the assessment of airway responsiveness to inhaled methacholine in mice using the forced oscillation technique (flexiVent; SCIREQ Inc, Montreal, Qc, Canada).

使用强迫振动技术在小鼠呼吸系统力学评价

The  forced oscillation technique (FOT) is a powerful, integrative and translational  tool permitting the experimental assessment of lung function in mice ...

生物学

Assessment of Respiratory Function in Conscious Mice by Double-chamber Plethysmography

Air volume changes created by a conscious subject breathing spontaneously within a body box are at the basis of plethysmography, a technique used to non-invasively assess some features of the respiratory function in humans as well as in laboratory animals. The present article focuses on the application of the double-chamber plethysmography (DCP) in small animals. It provides background information on the methodology as well as a detailed step-by-step procedure to successfully assess respiratory function in conscious, spontaneously breathing animals in a non-invasive manner. The DCP can be used to monitor the respiratory function of multiple animals in parallel, as well as to identify changes induced by aerosolized substances over a chosen time period and in a repeated manner. Experiments on control and allergic mice are used herein to demonstrate the utility of the technique, explain the associated outcome parameters, as well as to discuss the related advantages and shortcomings. Overall, the DCP provides valid and theoretically sound readouts that can be trusted to evaluate the respiratory function of conscious small animals both at baseline and after challenges with aerosolized substances.

The objective of the present article is to provide a detailed description of the recommended procedures to evaluate respiratory function in conscious mice by double-chamber plethysmography.

双室 Plethysmography 对清醒小鼠呼吸功能的评价

Air volume changes created by a conscious subject breathing spontaneously within a body box are at the basis of plethysmography, a technique used to ...

Hyperpolarized 129Xe Lung MRI and Spectroscopy in Mechanically Ventilated Mice

Hyperpolarized (HP) xenon-129 (129Xe) is an inhaled magnetic resonance imaging (MRI) contrast agent with unique spectral and physical properties that can be exploited to quantify pulmonary physiology, including ventilation, restricted diffusion (alveolar-airspace size), and gas exchange. In humans, it has been used to evaluate disease severity and progression in a variety of pulmonary disorders and is approved for clinical use in the United States and United Kingdom. Beyond its clinical applications, the ability of 129Xe MRI to noninvasively assess pulmonary pathophysiology and provide spatially resolved information is valuable for preclinical research. Among animal models, mice are the most widely used due to the accessibility of genetically modified disease models. Here, 129Xe MRI is promising as a minimally invasive, radiation-free, and sensitive technique to longitudinally monitor lung disease progression and therapy response (e.g., in drug discovery). This technique can extend to preclinical applications by incorporating an MRI-triggered, free-breathing apparatus or mechanical ventilator to deliver gas. Here, we describe the steps and provide checklists to ensure robust data collection and analysis, including creating a thermally polarized xenon gas phantom for quality control, optimizing polarization, animal handling (sedation, intubation, ventilation, and care for mice), and protocols for ventilation, restricted diffusion, and gas exchange data. While preclinical 129Xe MRI can be applied in various animal models (e.g., rats, pigs, sheep), this protocol focuses on mice due to the challenges posed by their small anatomy, which are balanced by their affordability and the availability of many disease models.

Hyperpolarized xenon MRI can quantify regional lung microstructure (air-space dimensions) and physiology (ventilation and gas exchange) in translational research and clinical care. Although challenging, it can provide comparable pulmonary insights in preclinical studies. This protocol describes the infrastructure and procedures needed to perform routine xenon lung MRI in mice.

机械通气小鼠的超极化 129Xe 肺 MRI 和光谱学

Hyperpolarized (HP) xenon-129 (129Xe) is an inhaled magnetic resonance imaging (MRI) contrast agent with unique spectral and physical properties that can ...

生物工程

Measuring Respiratory Function in Mice Using Unrestrained Whole-body Plethysmography

Respiratory dysfunction is one of the leading causes of morbidity and mortality in the world and the rates of mortality continue to rise. Quantitative assessment of lung function in rodent models is an important tool in the development of future therapies. Commonly used techniques for assessing respiratory function including invasive plethysmography and forced oscillation. While these techniques provide valuable information, data collection can be fraught with artefacts and experimental variability due to the need for anesthesia and/or invasive instrumentation of the animal. In contrast, unrestrained whole-body plethysmography (UWBP) offers a precise, non-invasive, quantitative way by which to analyze respiratory parameters. This technique avoids the use of anesthesia and restraints, which is common to traditional plethysmography techniques. This video will demonstrate the UWBP procedure including the equipment set up, calibration and lung function recording. It will explain how to analyze the collected data, as well as identify experimental outliers and artefacts that results from animal movement. The respiratory parameters obtained using this technique include tidal volume, minute volume, inspiratory duty cycle, inspiratory flow rate and the ratio of inspiration time to expiration time. UWBP does not rely on specialized skills and is inexpensive to perform. A key feature of UWBP, and most appealing to potential users, is the ability to perform repeated measures of lung function on the same animal.

The assessment of respiratory physiology has traditionally relied upon techniques, which require restraint or sedation of the animal. Unrestrained whole-body plethysmography, however, provides precise, non-invasive, quantitative analysis of respiratory physiology in animal models. In addition, the technique allows repeated respiratory assessment of mice allowing for longitudinal studies.

用奔放的整体体积描记测量呼吸功能的影响

Respiratory dysfunction is one of the leading causes of morbidity and mortality in the world and the rates of mortality continue to rise. Quantitative ...

In vivo Evaluation of Mucociliary Clearance in Mice

Respiratory motile cilia, specialized organelles of the cell, line the apical surface of epithelial cells lining the respiratory tract. By beating in a metachronal, synchronal fashion, these multiple, motile, actin-based organelles generate a cephalad fluid flow clearing the respiratory tract of inhaled pollutants and pathogens. With increasing environmental pollution, novel viral pathogens and emerging multi-drug resistant bacteria, cilia generated mucociliary clearance (MCC) is essential for maintaining lung health. MCC is also depressed in multiple congenital disorders like primary ciliary dyskinesia, cystic fibrosis as well as acquired disorders like chronic obstructive pulmonary disease. All these disorders have established, in some case multiple, mouse models. In this publication, we detail a method using a small amount of radioactivity and dual-modality SPECT/CT imaging to accurately and reproducibly measure MCC in mice in vivo. The method allows for recovery of mice after imaging, making serial measurements possible, and testing potential therapeutics longitudinally over time. The data in wild-type mice demonstrates the reproducibility of the MCC measurement as long as adequate attention to detail is paid, and the protocol strictly adhered to.

In this publication, we describe protocols for assessing airway mucociliary clearance (MCC) in mice in vivo utilizing dual-modality radionuclide imaging. This protocol is designed for a single photon emission computed tomography (SPECT) and computed tomography (CT) acquisition protocol using mouse whole body (MWB) collimators in a dual SPECT/CT system.

在体内评估小鼠的粘液清除

Respiratory motile cilia, specialized organelles of the cell, line the apical surface of epithelial cells lining the respiratory tract. By beating in a ...

Evaluation of Lung Function in an Ex vivo Murine Model

Respiratory mechanics are a key area of study in defining and treating lung pathologies by assessing functional lung capacity. Lung mechanics can be evaluated through various lung maneuvers that involve different oscillatory waveforms. When applied to the lungs, these maneuvers measure multiple variables, such as pressure, volume, and flow, based on the response to the waveforms. These signals are then computed and analyzed to determine parameters such as hysterisivity, resistance, compliance, tissue damping, and tissue elastance, providing a detailed assessment of overall lung function. The analysis of respiratory mechanics is particularly important in evaluating donor lungs for lung transplantation. The present protocol is the first of its kind, offering a comprehensive and reproducible stepwise method for assessing respiratory mechanics using an ex vivo murine model. It includes details on the selected animal model, lung recovery, storage and preservation, and experimentation using a forced oscillation technique-based system. Additionally, it outlines data analysis, clinical significance, and the applications of the forced oscillation technique in studying an ex vivo model.

The present protocol describes a stepwise method for analyzing the respiratory mechanics of an ex vivo murine model using the forced oscillation technique (FOT).

离体小鼠模型中肺功能的评价

Respiratory mechanics are a key area of study in defining and treating lung pathologies by assessing functional lung capacity. Lung mechanics can be ...

表型鼠标肺功能

摘要

探索更多视频