Name: phenotyping mouse pulmonary function in vivo with the lung diffusing capacity
Uploaded: 2015-01-06T10:00:00.000+00:00
Duration: 7 min 13 s
Description: Watch this Scientific Journal Video about Phenotyping Mouse Pulmonary Function In Vivo with the Lung Diffusing Capacity at JoVE.com

This work was supported by NIH HL-10342

注：すべての動物のプロトコルはジョンズ·ホプキンス大学動物実験委員会によって承認された。 1.動物の準備<ol><li>以下のステップ2.3に概説されているようケタミンとキシラジンでそれらを麻酔により、DFCO測定に6 C57BL / 6対照マウスを準備します。 </li><li>対照と同様の手順を使用して、表1に示す異なる肺病変を有する他のすべてのマウスを準備する。これらのモデルのそれぞれを確立するために必要な具体的な詳細は、関連文献に見出される。対照マウスと他の病理学的コホートのものは、年齢のすべての6-12週間です。 </li></ol>一酸化炭素に対する拡散係数の2.測定（DFCO） <ol><li>窒素、酸素、ネオン、及び一酸化炭素のピークを測定する機械で供給されたガスクロマトグラフモジュールを設定する。このアプリケーションでは唯一のネオンとCOデータを使用する。 注：この装置は、分子のSを使用しています12.00ミクロンフィルム、320.00ミクロンID及び長さ10mで、キャリアガスとしてヘリウムを用いてカラムをIEVE。クロマトグラフカラムは、0.8ミリリットルの容量を持っていますが、我々は、サンプルとの接続配管の適切なクリアを確実にするために2ミリリットルを使用していました。 </li><li>各実験日の開始時に、マウスからのサンプルの測定を行う前に、約0.5％のNeと、0.5％のCOを含むガス混合物バッグから直接の2mlサンプルを取り、空気バランスをとる、および較正するために、このサンプルを使用ガスクロマトグラフ。 </li><li>ケタミン（90ミリグラム/ kg）およびキシラジン（15ミリグラム/ kg）でマウスを麻酔し、反射運動の欠如によって麻酔を確認する。乾燥を防ぐために、目に獣医軟膏を適用します。 （非常に若いマウスでは成人で18 Gまたは20 G）スタブ針カニューレをマウスにTracheostomize。 注：DFCOは麻酔後に10分未満で完了し、すべての機械的な換気または他の手順の前にされている。 </li><li> 6週齢よりも大きいマウスでは3 mlシリンジtを使うO混合ガスバッグからのガス0.8mlの撤回。気管カニューレにシリンジを接続し、すぐに肺を膨らませる。メトロノームを使用して、9秒をカウントしてから、すぐに0.8ミリリットル（呼気）を撤回。 </li><li>この撤回0.8ミリリットルが室内空気との2ミリリットルに空気を吐き出さ希釈し、それは少なくとも15秒間休むことができます。その後、分析のためにガスクロマトグラフに全サンプルを注入する。 </li><li>この第DFCO試料を分析しながら、ガス混合バッグから第0.8ミリリットルでマウス肺を膨張し、最初のサンプルと同じでこのサンプルを処理する。 2 DFCO測定を平均化する。 注：0.8 mlの体積が非常に若いマウスの肺で測定を行うには大きすぎるので、2週齢の幼いマウスにおいて測定のために、0.4 mlの容量を使用する。これは、6週間以上経過したマウスの0.8容を使用することをお勧めし、0.4mlの容量がいくつかのマウスのために必要とされる場合、それは研究されてコホート内のすべてのマウスについて一貫して使用されるべきである。 </li><li> DFCOを計算（9 CO / CO c）は/（Neが9 / Neとc）は、cおよび9添字注入校正ガスの濃度は、それぞれ、9秒の息止め時間後に除去したガスを参照する- 1である。 </li><li>分析し、一方向ANOVAとの差を比較し、すべてのコホートマウスにおける多重比較のためのテューキーの補正との有意水準を評価する。 P &lt;0.05として重要な価値を考えてみましょう。 注：ここで使用したマウスのすべてがここで報告されていない肺換気、力学、肺洗浄液、または組織学のいくつかのその後の測定を伴う実験研究の一部であった。この方法は、対照マウスに上記行ったように、すべての実験モデルにおいて同様であるのでさらに、種々の病理学的モデルからの結果のみを提示する。これらのモデルの詳細については、補足表に示されている。 </li><li>深いanestheにより動物を安楽死させるチック過剰摂取は、頸椎脱臼または断頭が続く。必要な場合には、さらに生物学的または組織学的処理および分析のために死亡したマウスからの肺細胞および/または組織を取り除く。 </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>

利害の対立はなく、開示することは何もない。

本研究では、マウス肺の能力を交換するガスを定量化するための新しいメトリックを定義した。このメトリックは、拡散能、すなわち、肺の主要な機能を測定する一般的な臨床測定、ガスを交換する能力に類似している。拡散容量は、簡単かつ迅速に、マウスおよびヒトの両方で行うことができる唯一の​​肺の機能的測定である。マウスにおける肺疾患の検出のために、主要な目的は、対?...

マウスは、現在の肺疾患の種々のモデル化に使用される主要な動物である。そのような病状をunderlyメカニズムを研究するために、表現型の方法は、それを病理学的変化を定量化することが必要とされている。換気力学が測定されている多くのマウス試験がありますが、これらの測定値は一般的に、通常、ヒトで行われ、肺機能の標準的評価とは無関係である。マウスおよびヒト対象において同等の測定を実行する能力は、ヒト疾患のマウスモデルの結果の翻訳を容易にすることができるので、これは残念なことである。 ヒト被験体における最も一般的かつ容易に行われる測定の一つは、一酸化炭素（DLCO）-1,2-ための拡散能であるが、この測定は、まれにしかマウスモデルで行われていない。手順は、しばしば扱いにくいまたはreqができるので、それは3-7報告されているこれらの研究では、部分的には、何のフォローアップ研究が行われていない複雑な装置uire。別のアプローチは、意識のあるマウスにおけるCOの拡散を測定することができるという利点を有する定常状態のシステムにおいて、CO再呼吸法を使用することである。しかし、この方法は非常に煩雑であり、結果は、マウスの換気のレベル並びにO 2およびCO 2濃度8.9で変化することができる。これらの困難は、そのいくつかの利点にもかかわらず、マウスでは肺の病理を検出する能力を拡散する日常的な使用を妨げているように見える。 マウスにおいて、拡散能力の測定に伴う問題を回避するために、マウスでそれを測定するための簡単な手段の詳細については、最近10に報告されている。手続きはすぐにガスを触発全体に等しい体積をサンプリングすることによって汚染されていない肺胞ガスをサンプリングする困難な問題を排除します。非常に再現性のある測定では、この手順の結果は、パのホストに敏感である一酸化炭素（DFCO）用の拡散係数と呼ばれる肺の表現型のthologic変化。 （CO 9 / CO c）に /（Neが9 / Neとc）は、cおよび9添字注入校正ガスおよび9秒の息止め時間後に除去したガスの濃度を表す、 - DFCOこうして1のように計算されるそれぞれ。 DFCO 1はCOのない取り込みを反映していない完全なすべてのCOの摂取、及び0を反映して、0と1の間で変化する無次元の変数である。 この発表では、この拡散能測定を行う方法を示し、そしてどのようにそれが気腫、線維症、急性肺損傷、およびウイルスおよび真菌感染を含むほぼすべての既存のマウス肺疾患モデルの変更を文書化するために使用することができる。

<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

マウスは、現在の肺疾患の種々のモデル化に使用される主要な動物である。このような病状の根底にあるメカニズムを研究するために、表現型の方法は、病理学的変化を定量化することが必要とされている。さらに、マウスモデルへの並進の関連性を提供するために、そのような測定を容易にヒトおよびマウスの両方で行うことができるテストであるべきである。残念ながら、現在の文献に肺機能のいくつかの表現型の測定は、ヒトへの直接のアプリケーションがあります。唯一の例外は、日常的にヒトにおいて行われた測定である一酸化炭素拡散能である。今回の報告では、迅速かつ簡単にマウスではこの拡散能を測定するための手段を説明する。手順は、1分ガス分析時間が続く、麻酔したマウスにおけるトレーサガスと短い肺膨張を伴う。私たちは、肺気腫、線維症、急性肺損傷、およびインフルエンザを含むいくつかの肺の病変を検出するためのこの方法の能力をテストし、真菌の肺感染症、ならびに若い仔における肺成熟をモニタする。結果は、すべての重要な肺病変の減少、ならびに肺成熟と拡散容量の増加を示す。肺拡散能のこの測定は、このように既存の病的な肺モデルのほとんどと表現型の構造変化を検出する能力を有する広い用途を有する肺機能試験を提供する。

図1は、アスペルギルス属およびインフルエンザ感染症の両方に有意な減少、ならびに線維症の有意な減少、気腫、急性があったグループA、B、C、D、Eにおける成体マウスからDFCO測定値を示しており、F.肺損傷モデル。 図2に、2-6週間のマウスの年齢などの経時DFCOでグループG発達的変化を示している。この時間経過にわたって肺の発達と、わずかではあるが有意な増?...

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.

表現型マウス肺機能<em&gt;インビボ</em&gt;肺拡散能力を持つ

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

10.5K ビュー.  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.

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

A Standardized Method for Measuring Internal Lung Surface Area via Mouse Pneumonectomy and Prosthesis Implantation

Pulmonary morphology, physiology, and respiratory functions change in both physiological and pathological conditions. Internal lung surface area (ISA), representing the gas-exchange capacity of the lung, is a critical criterion to assess respiratory function. However, observer bias can significantly influence measured values for lung morphological parameters. The protocol that we describe here minimizes variations during measurements of two morphological parameters used for ISA calculation: internal lung volume (ILV) and mean linear intercept (MLI). Using ISA as a morphometric and functional parameter to determine the outcome of alveolar regeneration in both pneumonectomy (PNX) and prosthesis implantation mouse models, we found that the increased ISA following PNX treatment was significantly blocked by implantation of a prosthesis into the thoracic cavity1. The ability to accurately quantify ISA is not only expected to improve the reliability and reproducibility of lung function studies in injured-induced alveolar regeneration models, but also to promote mechanistic discoveries of multiple pulmonary diseases.

Internal lung surface area (ISA) is a critical criterion for assessing lung morphology and physiology in lung diseases and injury-induced alveolar regeneration. We describe here a standardized method that can minimize the measurement bias for ISA in both lung pneumonectomy and prosthesis implantation mouse models.

マウス肺切除術および義歯移植による内臓肺表面積の標準化法

Pulmonary morphology, physiology, and respiratory functions change in both physiological and pathological conditions. Internal lung surface area (ISA), ...

発生生物学

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.

肺気腫とタバコ煙曝露マウスにおける末梢気道リモデリングの自動測定

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 ...

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.

マウス肺における圧力 - 容積曲線の測定

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.

腹腔内のブドウ糖負荷試験、肥満や呼吸器アウトカムに対する代謝が異常の影響を研究する肺機能の測定や肺の固定

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・感染学

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.

繰り返しオゾン暴露によるマウスの慢性閉塞性肺疾患モデルの生成

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).

強制振動法を用いたマウスにおける呼吸器系の力学の評価

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.

ダブル室容積脈波による意識下マウスにおける呼吸機能の評価

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.

人工呼吸器マウスにおける過分極 129Xe肺MRIおよび分光法

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

生物工学

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.

拘束されていない全身プレチスモグラフィを使用したマウスにおける呼吸機能の測定

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.

マウスにおける粘膜クリアランスのインビボ評価

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

表現型マウス肺機能

要約

さらに動画を探す

この動画の章