用奔放的整体体积描记测量呼吸功能的影响
Summary
呼吸生理的评估方法时，需要克制的动物或镇静历来依赖。无节制的全身体积描记法，然而，提供了在动物模型中的呼吸生理学的精确，非侵入性，定量分析。此外，该技术允许重复小鼠允许纵向研究的呼吸系统评估。
Abstract
呼吸功能障碍的发病率和死亡率在世界上领先的原因和死亡的发生率持续上升的。肺功能的啮齿动物模型定量评估是未来疗法的发展的一个重要工具。常用的技术评估呼吸功能，包括侵入式体积描记法及强迫振动。尽管这些技术提供了有价值的信息，数据集合可以是充满了伪像和实验变异性，因为需要对麻醉和/或动物的侵入性仪器。与此相反，无节制的全身体积描记法（UWBP）提供了一个精确的，非侵入性，定量由此来分析呼吸参数的方式。该技术避免了使用麻醉和限制的，这是常见的传统的体积描记技术。这部影片将展示UWBP程序包括设备安装，校准和肺功能记录。它将解释如何分析收集到的数据，以及确定实验离群和文物而导致的动物的运动。使用这种技术获得的呼吸参数包括潮气量，每分钟通气量，吸气占空比，吸气流量和吸气时间到期时间的比值。 UWBP不依赖于专门的技能和价廉来执行。 UWBP的一个关键特征，并且最吸引潜在的用户，是在同一个动物进行肺功能的重复测量的能力。
Introduction
肺功能障碍是发病率和死亡率在世界上领先的原因之一。该条件的特点是不充分的氧气交换，等同于咳嗽，胸痛和呼吸困难。呼吸系统疾病占死亡率的全球1％〜10％。根据世界卫生组织，死亡率都将上升，由于长期吸烟，环境污染和职业的刺激。 UWBP是一个有益的补充学习肺的生理，有力地恭维传统的生化和组织学分析2。其他程序用于肺癌的评估不提供相同的优点UWBP。侵入体积描记法是一种常用的技术，需要对动物进行anesthetised 3,4，因此，导致呼吸测量不一定是反射的自然状态。此外，机械通气和化学挑战要求排除未来测量3,4。收集的呼吸数据的另一种方法是通过强迫振荡，这是更敏感的微细化改变呼吸参数相比UWBP 5。强迫振荡，然而，一种侵入性的技术，并且需要动物终止数据收集5-7。
UWBP包括将动物的专业室内。在吸气过程中，潮气的空气被加热和肺部增加水蒸气压力范 围内的加湿，并使气体8的热膨胀。这种效应导致的净变化在空气体积产生的体积描记器室8内的压力增加。过期创建从动物呼吸波形期间发生相反。波形分析，然后用从呼吸迹测量：呼吸率（次/ min），总呼吸周期时间（秒），吸气/呼气时间（钛/碲，秒），由于各潮气量的压力变化（P T）。 <stroNG>图1显示了每个测量起源于呼吸的痕迹。这些测量是简单的计算和多种呼吸参数可以从这些测量得到的。这些参数包括：潮气量（空气的体积的正常吸气和呼气之间的移动），每分钟通气量（气体从每分钟肺部吸入的体积），吸气占空比（吸气时间与总呼吸周期的持续时间的百分比），并吸气流量（空气的启发在一个给定的时间量）。
UWBP提供了在动物模型中的呼吸生理学的精确，非侵入性，定量分析，并且可以用于测量呼吸性疾病和肺功能6,9的进展。相反，其他体积描记技术，UWBP避免使用麻醉，限制和产生的文物和实验变异6,9侵入性操作的。麻醉可以抑制呼吸，改变心脏速率，并且可以是具有挑战性的调节10。限制导致增加呼吸因额外的压力，通过皮质酮和肾上腺素释放出11,13。 UWBP的主要特点是反复的生理评估，使之适合于纵向研究。 UWBP强烈建议肺生理的纵向评估，并提供了一个宝贵的技能为未来的呼吸药物评估。
博来霉素，卵清蛋白，和缺氧已被用于诱导呼吸道挑战在几个研究和UWBP已经成功地测量准确肺生理评估7,9,13-16。中描述的协议被设计为标准成人实验小鼠。然而，UWBP已适应其他动物，如大鼠，豚鼠，以及非人类灵长类17-20。 UWBP并不限于只以评估肺功能障碍，但也被用于为肺成熟3的评估。UWBP的多功能性，简洁性和可重复性已经建立起了一支优秀的技术评估动物肺功能。各种软件（见材料和设备表）将被要求执行此过程。一个有经验的科学家将能够在1小时内执行该协议与鼠标。
Protocol
Representative Results
Discussion
这里描述的技术是奔放和麻醉的小鼠呼吸参数评估一种非侵入性的方法。该协议的优势包括它的简单性和精确性纵向测量肺功能以最少的人工制品。有，然而，一些局限性和关键步骤要注意有关的过程。首先，最重要的是，鼠标必须留室至少五秒钟内平静。增加的压力会破坏鼠标的呼吸模式，从而提供不同的结果（ 图6a）。这种缺点可能会保持和处于倍于预期。但是，更换鼠标在其?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
We would like to thank Prof David Walker for his technical advice and provision of equipment in the development of this technique. This work is supported by the Victorian Government’s Operational Infrastructure Support Program. This work was partly supported by the Victorian Government’s Operational Infrastructure Support Program.
Materials
| LabChart 7 software (for Macintosh) | ADINSTRUMENTS | MLU60/7 | used in protocol step 4 |
| PowerLab 8/30 (model ML870) | ADINSTRUMENTS | PL3508 | |
| Octal Bridge Amp (model ML228) | ADINSTRUMENTS | FE228 | |
| Black BNC to BNC cable (1m) | ADINSTRUMENTS | MLAC01 | |
| Macintosh OS | Apple Inc. | – | Mac OS X 10.4 or later |
| Surgipack Digital Rectal Thermometer | Vega Technologies | MT-918 | |
| Grass volumeteric pressure transducer PT5A | Grass Instruments Co. | Model number PT5A; serial No. L302P4. | |
| 1ml Syringe | Becton Dickinson (BD) | 309628 | |
| 5ml serological syringe pipettes | Greiner Bio One | 606160 | Connected via plastic tubing |
| Balance/Scales | VWR International, Pty Ltd | SHIMAUW220D | Any weighing balance with of 0.1 gram resolution |
| HM40 Humidity & temperature meter | Vaisala | HM40A1AB | |
| Barometer | Barometer World | 1586 | |
| Laboratory tubing | Dow Corning | 508-101 | Used to connect water column to the syringe and pressure transducer |
| Cylindrical Perspex Chamber | Dynalab Corp. | Custom built cylindrical chamber with internal dimensions as follows: 50mm(w) x 1500mm(l). There are two lids for each side, with dimensions 80mm(l) x 80mm(w). Each lid has a 60mm wide circular hole cut on the face of the lid 50mm deep. This allows the chamber to fit into the lid. A rubber ring is fitted around each hole of the lid where the chamber will fit. For attachment of syringe and pressure transducer, the openings are 5mm in diameter. For attachment of humidity probe, the openings are 25mm in diameter. | |
| 80% Ethanol (4L) | VWR International, Pty Ltd | BDH1162-4LP |
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