一种可重复的重症监护病房导向内毒素模型在大鼠中的应用
Summary
在这里，我们提出了一种可重复的重症监护病房导向的大鼠内毒素模型。
Abstract
脓毒症和脓毒性休克仍然是重症监护病房的主要死因。尽管脓毒症管理有了显著改善，但死亡率仍在 20% 至 30% 之间。迫切需要新的治疗方法来减少脓毒症相关的多器官衰竭和死亡。强大的动物模型允许一种或多种治疗方法，以及测试它们对生理和分子参数的影响。在本文中，介绍了一个简单的动物模型。
首先，全身麻醉是通过使用挥发性或腹膜内麻醉在动物中诱导的。放置静脉导管（尾静脉）、气管切开术和插入动脉内导管（尾动脉）后，开始机械通气。记录平均动脉血压、动脉血氧饱和度和心率的基线值。
注射溶解在磷酸盐缓冲盐水中的脂多糖（1毫克/千克体重）通过toll样受体4诱导强烈且可重复的炎症反应。液体校正以及去甲肾上腺素的应用是根据完善的协议进行的。
本文中介绍的动物模型易于学习，并且强烈面向重症监护病房的临床脓毒症治疗，包括镇静，机械通气，连续血压监测和重复血液采样。此外，该模型是可靠的，允许根据动物研究的3R（减少，替换，精炼）原则，有限数量的动物提供可重复的数据。虽然脓毒症研究中的动物实验不能轻易被取代，但重复测量可以减少动物，并且保持脓毒性动物麻醉可以减轻痛苦。
Introduction
脓毒症及其更严重的形式，脓毒性休克，是感染基础上的综合征，导致细胞因子释放的过度炎症反应，导致生理和生化变化，免疫防御受到抑制，致命结果1，2。这种不平衡的炎症反应导致器官功能障碍和各种重要器官（如肺，肾和肝）的器官衰竭。脓毒症为 37%3，是患者入住重症监护病房 （ICU） 的最常见原因之一。脓毒症的死亡率目前约为20-30%4。早期和有效的抗生素治疗至关重要5.液体和血管加压药需要及早安装复苏，除此之外，治疗是纯粹的支持性6.
脓毒症被定义为已证实或疑似细菌、真菌、病毒或寄生虫感染，伴有器官功能障碍。当进一步的心血管衰竭对单独液体治疗无反应，并且存在超过 2 毫摩尔/升的乳酸水平时，符合脓毒性休克标准2。脓毒症相关器官衰竭可能发生在任何器官中，但在心血管系统、大脑、肾脏、肝脏和肺部非常常见。大多数脓毒症患者需要气管插管，以保护患者的气道，防止误吸，并使用高比例的吸入氧气进行呼气末正向通气，以防止或克服缺氧。为了耐受气管插管和机械通气，患者通常需要镇静。
内毒素，如脂多糖（LPS）作为革兰氏阴性菌膜的组分，通过toll样受体（TLR）诱导强烈的炎症反应47。激活定义的途径可确保稳定的炎症反应。细胞因子诱导的中性粒细胞化学牵伸缩蛋白1（CINC-1），单核细胞化学吸引蛋白1（MCP-1）和白细胞介素6（IL-6）等细胞因子在该模型8中被称为严重程度和结局的预后因素。静脉注射LPS应用已成功用于研究大鼠脓毒症的各个方面8，9。
脓毒症的治疗仍然是一个挑战，特别是由于缺乏预测性动物模型。如果内毒素血症伴全身炎症的激活是开发药物治疗的充分模型是值得商榷的。然而，通过众所周知的LPS诱导TLR 4通路可以获得重要的知识。
Protocol
Representative Results
Discussion
这里描述的方案允许高度可重复，但简单易学的败血症模型，可以根据研究问题进行调整。可以连续收集涉及器官功能的基本体内数据，例如心率，血压和外周动脉血氧饱和度，并且可以在整个实验过程中重复进行血液采样。此外，可以安装有关液体置换方案和血管加压药支持的修改。鉴于动物的血流动力学稳定性，实验可以在几个小时内进行，如先前报道的8。
<p class="jove_c…Divulgations
The authors have nothing to disclose.
Acknowledgements
作者要感谢Beatrice Beck-Schimmer（医学博士）和Erik Schadde（医学博士）的批判性检查和他们对本手稿的宝贵贡献。
Materials
| 2-0 silk sutures | Ethicon, Sommerville, NJ | K833 | Standard surgical |
| 26 intravenous catheter | Becton Dickinson, Franklin Lakes, NJ | 391349 | Standard anesthesia equipment |
| 6-0 LOOK black braided silk | Surgical Specalities Corporation, Wyomissing, PA | SP114 | Standard surgical |
| Alaris Syringe Pump | Bencton Dickinson | ||
| Betadine | Mundipharma, Basel, Switzerland | 7.68034E+12 | GTIN-number |
| Curved fine tips microforceps | World precision instruments (WPI), Sarasota, FL | 504513 | Facilitates vascular preparation |
| Fine tips microforceps | World precision instruments (WPI), Sarasota, FL | 501976 | Tips need to be polished regularly |
| Infinity Delta XL Anesthesia monitoring | Draeger, Lübeck, Germany | ||
| Isoflurane, 250 mL bottles | Attane, Piramal, Mumbai, India | LDNI 22098 | Standard vet. equipment |
| Ketamine (Ketalar) | Pfitzer, New York, NY | ||
| Lipopolysaccharide (LPS) from Escherichia coli, serotype 055:B5 | Sigma, Buchs, Switzerland | ||
| Q-tips small | Carl Roth GmbH, Karlsruhe, Germany | EH11.1 | Standard surgical |
| Ringerfundin | Bbraun, Melsungen, Germany | ||
| Tec-3 Isofluorane Vaporizer | Ohmeda, GE-Healthcare, Chicago, IL | not available anymore | Standard vet. equipment |
| Xylazine (Xylazin Streuli) | Streuli AG, Uznach, Switzerland |
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