小鼠运动耐力的评估没有一个冲击电网的使用：另一种强迫运动
Summary
A method to assess exercise endurance in laboratory mice without the use of a shock grid is demonstrated. This method is a humane refinement that can decrease the confounding effects of stress on experimental parameters.
Abstract
利用实验室小鼠模型，负责耐力运动的代谢好处分子途径开始进行定义。评估小鼠运动耐力的最常用的方法利用强制在电动跑步机上搭载了冲击电网运行。动物谁退出运行是由移动跑步机带压入，可提供电动足底电击的网格;为了躲避不良刺激，将小鼠返回到在皮带上运行。然而，回避行为和心理压力，由于利用冲击装置可以与定量运行的耐力，以及对运动后血清激素和细胞因子水平变乱的测量产生干扰。在这里，我们展示和验证一个精致的方法来衡量在天真的C57BL / 6小鼠的实验室在电动跑步机上跑步的耐力没有利用冲击电网。当小鼠preacclimated到跑步机，它们与步态自行运行速度具体到每个按钮鼠ê。使用冲击网格被替换温和鼓励使用压舌板，加上灵敏度自愿愿意在鼠标的一部分运行人类操作员。清楚的端点用于定量运行时间到用尽每只小鼠被定义，并反映在用尽的行为体征如叉开姿势和呼吸困难。此方法是一种人性化的细化也减少应激对实验参数的混杂影响。
Introduction
肥胖，胰岛素抵抗和2型糖尿病是会对美国和全球范围内的人口1-4的健康产生深远的影响相互关联的代谢紊乱。耐力运动可预防，以及治疗，这些条件5,6。而且，步态速度和耐力的评估被用于虚弱，肌肉衰减症临床上的诊断测试，以及其它疾病的后果，如慢性阻塞性肺病，在人类对象7。
耐力运动对身体成分和胰岛素敏感性的有益效果背后的生化途径开始被阐明，采用显示增强或运动能力降低8-11的基因或药物基因小鼠。然而，许多这样的研究已经利用装有电网的冲击，迫使老鼠跑8-11电动跑步机。动物谁退出运行是由推运动跑步机皮带上，可提供电动足底电击的网格;为了躲避不良刺激，将小鼠返回到在皮带上运行。这些程序可能会引入心理压力和回避行为的影响的实验参数12的混杂因素。测量耐久的使用光束断在笼车轮运行的装置或定量的其它方法，如动态活动的定量，可通过昼夜周期，焦虑，无意训练，或食物寻求行为12-16的调制被混淆。此外，这些程序需要单个壳体，心理压力的另一个来源为小鼠。因此，需要直接测量运动耐力的不是压力混淆。
为了避免这些问题，我们的实验室已经开发并验证的方法来评估最大运行能力和使用电动跑步机不能球菌持续的运行速度，未受过训练的，天真的小鼠pped与冲击电网。在运行的输送带，其中休克网格通常位于末端的空间，然后变成为小鼠休息的平台，并提供用于该拒绝运行坐下，直到从装置中取出小鼠的地方。小鼠鼓励人类观察者用轻轻拍打或用压舌板，加上灵敏度自愿意愿鼠标的一部分运行感人运行。此方法已被用来量化不同的肌肉衍生的细胞因子白细胞介素15（IL-15）16,17表达基因修饰和控制C57BL / 6小鼠之间的差异在运动耐力。此方法是一种人性化的精致的降低因使用冲击电网的负筋的混杂效应。
Protocol
Representative Results
Discussion
这里描述的是一种方法，使用电动跑步机不使用电网的冲击，以评估自愿耐力跑在实验室小鼠。这个方法可以揭示之间分线C57BL / 6小鼠的相差在细胞因子IL-15，这又导致在背后运动耐力16,17因子表达的差异表达的差异。在符合原则的“三R”在实验动物科学，这种方法可以作为一种更人性化的选择，或求精，到利用冲击电网8-11被迫行使协议。强迫运动也可以引入心理压力和两个运行…
Disclosures
The authors have nothing to disclose.
Acknowledgements
通过价值评议＃从退伍军人事务部（LSQ）BX001026，并利用资源和设施在弗吉尼亚州普吉特海湾卫生保健系统中，转基因核心资源在卓越华盛顿弥敦道冲击中心的大学老龄化的基本生物学支持（NIA＃5P30AG-013280），和华盛顿糖尿病内分泌科研究中心的大学（美国国立卫生研究院＃P30 DK-17047）。我们感谢辛西娅Pekow DVM和卡里属Koszdin DVM，弗吉尼亚州普吉特海湾，提供对稿件有益的意见。
Materials
| Open Rodent Treadmill Exer-3/6 | Columbus Instruments, Columbus OH | 1050RM | This catalog number is for models without shock grid. Shock grids can be removed manually from older models (Eco 3/6) |
| Sani Cloth Germicidal Towlettes | PDI- Professional Disposables, Inc., Orangeburg, NY | n/a; usually ordered through local facility | Contains 10% isopropyl alcohol; any equivalent product can be used. |
| Tongue depressors | any local supplier | n/a | |
| Laboratory timer | any supplier | n/a | |
| IL-15 TG mice* | JAX, Bar Harbor, ME | o11002 | Murine IL-15 transgene expressed from modified human alpha-skeletal actin promotor with altered signal sequence to facilitate secretion. |
| C57BL/6J mice (wild-type)* | JAX, Bar Harbor, ME | ooo664 | Control mice for IL-15 TG |
| IL-15 KO mice* | Taconic Farms, Germantown, NY | 4269-M | Homozygous IL-15 "knockout" mice on C57BL/6 background |
| C57BL/6NTac (wild-type)* | Taconic Farms, Germantown, NY | B6-M | Control mice for IL-15 KO |
| *Optional; mouse lines and treatments can be specific to the experimental protocol. |
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