调查轻度创伤性脑损伤海马电路功能的改变
Summary
一个多层面的方式来调查海马电路的功能变化进行了解释。电技术，以及受伤的协议，行为检测和区域的清扫方法。可以应用这些技术的组合，以类似的方式用于其他大脑区域和科学问题。
Abstract
创伤性脑损伤（TBI）折磨着每年超过170万人在美国，即使是轻微的脑外伤可能会导致持久性神经损伤1。普及和禁用的症状所经历的TBI幸存者，记忆障碍和减少癫痫发作阈值，被认为是介导的海马脑外伤引起的功能障碍2,3。为了演示如何改变伤后在小鼠海马的电路功能造成不利影响的行为，我们采用横向液压冲击伤，常用的TBI动物模型，再现了人类TBI的许多功能，包括神经细胞的损失，胶质细胞增生和离子扰动4 – 6。
在这里，我们展示了一个组合的方法调查TBI对海马功能障碍。我们的方法集成了多种体外生理技术结合起来，与动物行为学和生化分析，以分析在海马-TBI后的变化。我们开始实验的伤害模式与行为分析，评估认知障碍，脑外伤。接下来，我们提供三个不同的体外记录技术：外场势记录，可视化全细胞膜片夹紧，和对电压敏感染料记录。最后，我们展示了次区域的海马-TBI后的神经化学和代谢变化的详细分析，可用于区域解剖的方法。
这些方法已被用于检查修改后的海马电路TBI和探测对方在网络电路功能的变化发生在齿状回的海马CA1次区域（ 见图1）。分析后TBI在各次区域的能力是必不可少的理解基本的机制，促进脑外伤引起的行为和认知ðeficits。
这里列出的多面性的系统，使调查人员推过去的表征现象引起的一种疾病状态（在这种情况下，TBI），并确定负责与TBI所观察到的病理机制。
Protocol
1。横向闭合性损伤中的作用麻醉的小鼠腹腔注射氯胺酮和甲苯噻嗪的混合物。鼠标的头部，然后准备切口用碘擦洗。 执行去骨瓣超过使用3毫米（外径）环锯的右顶叶面积。 安全鲁尔-LOC针轮毂（内直径为3毫米）在骨瓣使用cyanoarylate和牙齿的丙烯酸。 24小时后，麻醉吸入异氟醚通过鼠标使用。 一旦恢复正常的呼吸，但之前鼠标的刺激变得敏感，通过液压冲…
Discussion
上面列出的每个技术有助于更深入的了解所观察到的行为赤字的内在机制造成的。通过结合从每个方法所取得的固有信息，我们能够检查更精确的生物学机制。
测量的fEPSPs是有用的为大，空间定义的区域的神经元量化净突触的功效。它也可以提供信息的一组细胞的潜力，经过突触可塑性，学习和记忆的神经相关的。这是一个非常有用的，因为它是第一点的电生理分析技?…
Divulgazioni
The authors have nothing to disclose.
Acknowledgements
作者想感谢艾略特他的资产阶级用于技术援助。这项工作是由国家机构的健康补助R01HD059288和R01NS069629的。
Materials
| Name of the equipment | Company | Catalogue number | Comments (optional) |
| Axopatch 200B amplifier | Molecular Devices | AXOPATCH 200B | Patch-clamp rig |
| Digidata 1322A digitizer | Molecular Devices | Patch-clamp rig | |
| MP-225 micromanipulator | Sutter | MP-225 | Patch-clamp rig |
| DMLFSA microscope | Leica | Patch-clamp rig | |
| Multiclamp 700B amplifier | Molecular Devices | MULTICLAMP 700B | Multipurpose (field) rig |
| Digidata 1440 digitizer | Molecular Devices | Multipurpos (field) rig | |
| MPC-200 micromanipulator | Sutter | MPC-200 | Multipurpose (field) rig |
| BX51WI microscope | Olympus | BX51WI | Multipurpose (field) rig |
| Axoclamp 900A amplifier | Molecular Devices | AXOCLAMP 900A | VSD rig |
| Digidata 1322 digitizer | Molecular Devices | VSD rig | |
| Redshirt CCD-SMQ camera | Redshirt | NCS01 | VSD rig |
| VT 1200S Vibratome | Leica | 14048142066 | |
| P-30 Electrode puller | Sutter | P-30/P | |
| cOmplete protease inhibitor | Roche | 11697498001 |
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Tags
InvestigationsAlterationsHippocampal Circuit FunctionMild Traumatic Brain InjuryTBINeurological ImpairmentsMemory DeficitsSeizure ThresholdHippocampal DysfunctionLateral Fluid Percussion InjuryAnimal ModelNeuronal Cell LossGliosisIonic PerturbationCombinatorial MethodEx Vivo Physiological TechniquesAnimal Behavior AnalysisBiochemical AnalysisCognitive DisabilityExtracellular Field Potential RecordingWhole-cell Patch-clampingVoltage Sensitive Dye RecordingRegionally Dissecting Subregions Of The HippocampusNeurochemical AnalysisMetabolic Analysis
Citazione di questo articolo
Smith, C. J., Johnson, B. N., Elkind, J. A., See, J. M., Xiong, G., Cohen, A. S. Investigations on Alterations of Hippocampal Circuit Function Following Mild Traumatic Brain Injury. J. Vis. Exp. (69), e4411, doi:10.3791/4411 (2012).