这项工作得到了皇家墨尔本医院神经科学基金会（A2087）的支持。

本研究由弗洛里动物伦理委员会（墨尔本大学，编号 22-025UM）根据澳大利亚科学目的动物护理和使用规范批准。从动物资源中心（澳大利亚）获得的 C57BL/6 雄性小鼠（8 周）用于本研究。
1. Headstage设计与制造
注意： 头部舞台 PCB 板是一个紧凑的 14 毫米 x 12 毫米四层板，设计用于直接放置在动物的头部。它使用商用放大器芯片（参见 材料表），所有设计和 Gerber 文件均可在线获取（GitHub 链接：https://github.com/dechuansun/Intan-headstage/tree/main/pcbway）。
<ol><li>向制造商提供以下规格：板厚：0.6 mm;最小跟踪/间距：4 mils;最小孔径：0.2 mm。</li>
	<li>在PCB组装过程中， 遵循以下顺序：<ol><li>使用设置为 350 °C 的热风枪将放大器芯片焊接到板上。</li>
		<li>焊接无源元件。</li>
		<li>焊接 SPI 连接器和电极连接器（参见 材料表）。</li>
	</ol></li>
	<li>在显微镜下检查焊接以保证质量。使用环氧树脂将 SPI 连接器固定到位，以增加稳定性。</li>
	<li>使用第三方记录软件和控制板（见 材料表）进行信号采集。有关详细说明，请参阅软件用户指南。</li>
	<li>设计的头台支持 8 个通道。在软件中，启用通道 8、9、12、13、20、21、22 和 23 进行录制。</li>
</ol>2. 电极制造
<ol><li>将 PFA 涂层的钨丝（参见 材料表）切割成不同电极类型的特定长度：前额叶皮层电极 （12 mm）、海马电极 （10 mm） 和接地电极 （6 mm）。</li>
	<li>将黄铜管（参见 材料表）切成 3 毫米的段。</li>
	<li>使用打火机去除每根焊丝末端 2 毫米的涂层，然后将电极丝牢固地焊接到黄铜管上。黄铜管的内径为 0.45 mm，外径为 0.60 mm。</li>
	<li>对于接地电极，将 M1.2 不锈钢螺钉（参见 材料表）焊接到电极上。将基于磷酸的助焊剂涂在螺钉上以增强焊接。焊接后，用酒精清洁螺丝。 注意： 在焊接过程中戴上手套进行保护。</li>
</ol>3. 外科手术
<ol><li>在用3%异氟烷和1L / min氧气流量的麻醉室中麻醉小鼠。</li>
	<li>将麻醉的小鼠放在加热垫上，并将其固定在立体定位框架中（参见 材料表）。</li>
	<li>将异氟烷的维持率调整为2.5-3%，并将氧气流量降低至500 mL/min。使用脚趾捏，确认动物是否仍处于深度麻醉状态。</li>
	<li>皮下注射0.5mg/kg的卡洛芬，并涂抹眼膏以保护眼睛。</li>
	<li>用聚维酮碘和80%乙醇剃须和消毒小鼠的头部。</li>
	<li>沿着头皮的中线做一个 8 毫米的切口，去除切口区域的结缔组织。</li>
	<li>使用过氧化氢清洁颅骨表面，注意不要接触周围的皮肤。</li>
	<li>将 bregma 和 lambda 标志对齐到同一水平，以便准确放置电极（bregma 和 lambda 是矢状缝合线与冠状缝线和 lambdoid 缝合线相交的地方）。</li>
	<li>在指定坐标处为参比电极/接地电极、锚螺钉（0.9 mm 钻头毛刺）和有源电极（0.3 mm 钻头毛刺）钻孔。</li>
	<li>将定制的电极（第 2 步）连接到立体定位框架臂上，并确保其垂直于大脑。</li>
	<li>将电极植入海马CA1区域（AP - 1.8 mm，ML - 1.3 mm，DV - 1.4 mm）。 注：AP，前后位;ML， 内侧;DV，背腹侧。</li>
	<li>在前额叶皮层（AP - 2.0 mm，ML - 0.3 mm，DV - 1.7 mm）中重复电极植入。</li>
	<li>用市售的强力粘合剂和牙科粘结剂固定电极（参见 材料表）。</li>
	<li>植入两个 1.2 毫米地脚螺钉（AP - 1.8 毫米，ML -1.6 毫米）以防止移动。</li>
	<li>将参比/接地电极直接与硬脑膜直接接触，位于 lambda 标志后方 2 毫米和单侧 2 毫米处。</li>
	<li>将电极的黄铜管侧连接到多通道插座连接器（参见 材料表），接地电极位于中间。</li>
	<li>在中间引脚的外部使用 0.8 mm 的热缩管进行隔离。</li>
	<li>用粘合剂和牙科粘合剂固定电极、锚固件螺钉和连接器。</li>
</ol>4.术后护理
<ol><li>为了减轻术后疼痛，根据疼痛评估，每 12-24 小时皮下注射 5-10 mg/kg 卡洛芬，持续三天。</li>
	<li>在开始任何记录或实验程序之前，为动物提供一周的恢复期。</li>
</ol>5. 录音程序
<ol><li>处理动物15分钟，每天两次，连续三天。</li>
	<li>轻轻地将鼠标周围的手合拢，不要施加过大的压力，从而捡起鼠标。</li>
	<li>将头盔板放在动物的头上30分钟，每天一次，连续三天。</li>
	<li>在录音当天，让动物适应录音室 30 分钟。</li>
	<li>将动物放在法拉第笼内的小型记录室中，以减少外部电气干扰。连接自定义头台进行录制。</li>
	<li>打开录音软件并选择 2.00 kHz 采样率。通过选择每个频道并按 空格键来禁用除 13 和 20 之外的所有频道。</li>
	<li>在 硬件带宽窗口中，将下限带宽设置为 2 Hz ，将上限带宽设置为 100 Hz。</li>
	<li>在 软件滤波窗口中，将低通滤波器调整为 100 Hz ，将高通滤波器调整为 2 Hz。</li>
	<li>通过单击“ 选择文件名”来选择存储路径，然后单击“ 录制”。</li>
	<li>以 10 分钟的适应期开始每个记录会话，然后进行 15 分钟的基线脑电图记录。</li>
	<li>基线记录后， 通过 腹膜内注射给药，并继续记录另外30分钟，不得拖延。 注意：有关所用药物的详细信息，请参阅“结果”部分。</li>
</ol>

小鼠大脑中的 LFP 记录用于认知研究和药物分析

<ol>
	<li>Einevoll, G. T., Kayser, C., Logothetis, N. K., Panzeri, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modelling+and+analysis+of+local+field+potentials+for+studying+the+function+of+cortical+circuits.">Modelling and analysis of local field potentials for studying the function of cortical circuits.</a> Nat Rev Neurosci. 14 (11), 770-785 (2013).</li><li>Buzsaki, G., Anastassiou, C. A., Koch, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+origin+of+extracellular+fields+and+currents-EEG,+ECOG,+LFP+and+spikes.">The origin of extracellular fields and currents-EEG, ECOG, LFP and spikes.</a> Nat Rev Neurosci. 13 (6), 407-420 (2012).</li><li>Sigurdsson, T., Stark, K. L., Karayiorgou, M., Gogos, J. A., Gordon, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impaired+hippocampal-prefrontal+synchrony+in+a+genetic+mouse+model+of+schizophrenia.">Impaired hippocampal-prefrontal synchrony in a genetic mouse model of schizophrenia.</a> Nature. 464 (7289), 763-767 (2010).</li><li>Witton, 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=Disrupted+hippocampal+sharp-wave+ripple-associated+spike+dynamics+in+a+transgenic+mouse+model+of+dementia.">Disrupted hippocampal sharp-wave ripple-associated spike dynamics in a transgenic mouse model of dementia.</a> J Physiol. 594 (16), 4615-4630 (2016).</li><li>Englot, D. J., Konrad, P. E., Morgan, V. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regional+and+global+connectivity+disturbances+in+focal+epilepsy,+related+neurocognitive+sequelae,+and+potential+mechanistic+underpinnings.">Regional and global connectivity disturbances in focal epilepsy, related neurocognitive sequelae, and potential mechanistic underpinnings.</a> Epilepsia. 57 (10), 1546-1557 (2016).</li><li>Pievani, M., De Haan, W., Wu, T., Seeley, W. W., Frisoni, G. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+network+disruption+in+the+degenerative+dementias.">Functional network disruption in the degenerative dementias.</a> Lancet Neurol. 10 (9), 829-843 (2011).</li><li>Sigurdsson, T., Duvarci, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hippocampal-prefrontal+interactions+in+cognition,+behavior+and+psychiatric+disease.">Hippocampal-prefrontal interactions in cognition, behavior and psychiatric disease.</a> Front Syst Neurosci. 9, 190 (2015).</li><li>Sun, 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=Effects+of+antipsychotic+drugs+and+potassium+channel+modulators+on+spectral+properties+of+local+field+potentials+in+mouse+hippocampus+and+pre-frontal+cortex.">Effects of antipsychotic drugs and potassium channel modulators on spectral properties of local field potentials in mouse hippocampus and pre-frontal cortex.</a> Neuropharmacology. 191, 108572 (2021).</li><li>Bokil, H., Andrews, P., Kulkarni, J. E., Mehta, S., Mitra, P. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronux:+A+platform+for+analyzing+neural+signals.">Chronux: A platform for analyzing neural signals.</a> J Neurosci Methods. 192 (1), 146-151 (2010).</li><li>Bozkurt, A., Lal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-cost+flexible+printed+circuit+technology+based+microelectrode+array+for+extracellular+stimulation+of+the+invertebrate+locomotory+system.">Low-cost flexible printed circuit technology based microelectrode array for extracellular stimulation of the invertebrate locomotory system.</a> Sens Actuator A Phys. 169 (1), 89-97 (2011).</li><li>Du, P., 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=High-resolution+mapping+of+in+vivo+gastrointestinal+slow+wave+activity+using+flexible+printed+circuit+board+electrodes:+Methodology+and+validation.">High-resolution mapping of in vivo gastrointestinal slow wave activity using flexible printed circuit board electrodes: Methodology and validation.</a> Ann Biomed Eng. 37, 839-846 (2009).</li><li>JoVE Science Education Database. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuroscience.+Histological+Staining+of+Neural+Tissue.">Neuroscience. Histological Staining of Neural Tissue.</a> JoVE. , (2023).</li></ol>

作者没有什么可透露的。

这里介绍的协议概述了构建定制头台的过程，该头台专门设计用于同时记录海马体（HIP）和前额叶皮层（PFC）中的双重局部场电位（LFP）。该协议中提供的详细步骤为研究人员提供了足够的信息，以彻底检查每个区域内以及HIP和PFC之间的信号通信。
定制设计的头级采用商用放大器芯片。虽然目前的配置支持 8 个通道的记录，但头级可以很容易地适应整个 32 个通道的容量，从?...

局部场电位 （LFP） 是指从细胞外空间记录的电活动，反映了一组局部神经元的集体活动。它们表现出多种频率范围，从 1 Hz 的慢波到 100 Hz 或 200 Hz 的快速振荡。 特定频段与学习、记忆和决策等认知功能有关 1,2。LFP 特性的变化已被用作各种神经系统疾病的生物标志物，包括痴呆和精神分裂症 3,4。分析 LFP 记录可以为与这些疾病相关的潜在病理机制和潜在的治疗策略提供有价值的见解。
双 LFP 记录是一种用于测量两个特定大脑区域内部和之间的局部电活动的技术。这种技术提供了一个宝贵的机会来研究不同大脑区域内部和之间发生的错综复杂的神经动力学和信号通信。先前的研究表明，检测单个大脑区域神经元特性的改变可能很复杂，但可以观察到区域间皮层通信的变化 5,6。因此，利用双LFP记录为解决这个问题提供了一种有效的方法。
海马-前额叶连接在调节认知功能方面起着至关重要的作用，功能障碍与各种神经系统疾病有关 7,8。这些区域的双电极记录可以提供有关这些相互作用的信息。不幸的是，关于在这些区域之间执行双电极LFP记录的方法的信息有限。此外，市售的记录设备通常价格昂贵，并且缺乏对特定实验设计的适应性。记录LFP的传统方法涉及使用屏蔽电缆将记录设备连接到植入动物大脑的电极。然而，这种方法容易受到运动伪影和环境噪声的影响，从而影响录制信号的质量和可靠性。
该协议描述了一种在小鼠海马体和前额叶皮层中执行双电极LFP记录的综合程序，使用可以放置在动物头部的低成本定制设计的头部。这些方法使研究人员能够研究两个离散大脑区域内的特定区域振荡模式，并探索这些区域之间的区域间信息交换和连通性。

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			<td>Intantech</td>
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			<td>Mouse stereotactic instrument</td>
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dual extracellular recordings in the mouse hippocampus and prefrontal cortex

记录局部场电位 （LFP） 的技术是一种电生理学方法，用于测量局部神经元群的电活动。它是认知研究的重要工具，特别是在海马体和前额叶皮层等大脑区域。这些区域之间的双LFP记录特别令人感兴趣，因为它们允许探索区域间信号通信。然而，执行这些记录的方法很少被描述，大多数商业记录设备要么价格昂贵，要么缺乏适应特定实验设计的适应性。本研究提出了一种在小鼠海马体和前额叶皮层中执行双电极 LFP 记录的综合方案，以研究抗精神病药物和钾通道调节剂对这些区域的 LFP 特性的影响。该技术可以测量LFP的特性，包括每个大脑区域内的功率谱以及两者之间的相干性。此外，还为这些实验开发了一种低成本、定制设计的记录设备。总之，该协议提供了一种在不同大脑区域记录高信噪比信号的方法，有助于研究大脑内的区域间信息通信。

Local field potentials (LFPs) refer to the electrical activity recorded from the extracellular space, reflecting the collective activity of a localized group of neurons. They exhibit a diverse range of frequencies, spanning from slow waves at 1 Hz to fast oscillations at 100 Hz or 200 Hz. Specific frequency bands have been associated with cognitive functions such as learning, memory, and decision making1,2. Changes in LFP properties have been used as biomarkers for various neurological disorders, including dementia and schizophrenia3,4. Analyzing LFP recordings can offer valuable insights into the underlying pathological mechanisms associated with these conditions and potential therapeutic strategies.
Dual LFP recording is a technique used to measure localized electrical activity within and between two specific brain regions. This technique provides a valuable opportunity to investigate the intricate neural dynamics and signal communication occurring within and between distinct brain regions. Prior studies have revealed that detecting alterations in the neuronal properties of individual brain regions can be complex, but changes in interregional cortical communication can be observed5,6. Therefore, the utilization of dual LFP recording offers a potent means to address this issue.
Hippocampal-prefrontal connectivity plays a crucial role in modulating cognitive functions, and dysfunction has been linked to various neurological disorders7,8. Dual electrode recordings of these regions can provide information about these interactions. Unfortunately, there is limited information available on methods for performing dual electrode LFP recordings between these areas. Moreover, commercially available recording devices are generally expensive and lack adaptability to specific experimental designs. The conventional method for recording LFPs involves using a shielded cable to connect the recording device to electrodes implanted in an animal's brain. However, this approach is susceptible to motion artifacts and environmental noise, impacting the quality and reliability of the recorded signals.
This protocol describes a comprehensive procedure for performing dual-electrode LFP recordings in the mouse hippocampus and prefrontal cortex, using a low-cost custom-designed headstage that can be placed on the animal's head. These methods enable researchers to investigate region-specific oscillatory patterns within two discrete cerebral regions and explore interregional information exchange and connectivity between these areas.

作者聚焦：使用双 LFP 记录方案研究药物对小鼠大脑信号的影响

小鼠海马体和前额叶皮层中的双重细胞外记录

This study presents a comprehensive protocol for performing dual-electrode LFP recordings in the mouse hippocampus and the prefrontal cortex to investigate the effects of drugs on LFP properties in these areas. This protocol provides a low-cost and ultra-light brain signal recording device that is fully optimized for cognitive research in mice. This study provides a means to record signals with high signal-noise ratios in different brain regions, facilitating the investigation of interregional information communication within the brain.

此处显示的结果表明，在四组C57BL / 6雄性小鼠（每组n = 8;年龄：8周;体重：24.0±0.42g）中测试的几种药物对局部场电位（LFPs）特性的影响。测试的药物包括抗精神病药物氯氮平、钾通道调节剂 4-氨基吡啶 （4-AP） 和瑞替加滨，以及对照载体生理盐水。
如图 1 所示，将小鼠放置在一个小记录室中，并使用定制设计的头部舞台从海马体 （HIP） 和前额叶皮层 ...

Watch this Scientific Journal Video about Dual Extracellular Recordings in the Mouse Hippocampus and Prefrontal Cortex at JoVE.com

该协议概述了使用定制设计的记录设备和电极来记录局部场电位并研究小鼠海马体和前额叶皮层中的信息流。

The technique of recording local field potentials (LFPs) is an electrophysiological method used to measure the electrical activity of localized neuronal ...

本研究提出了一种在小鼠海马体和前额叶皮层中执行双电极 LFP 记录的综合方案，以研究药物对这些区域的 LFP 特性的影响。该协议提供了一种低成本和超轻的脑信号记录设备，该设备针对小鼠的认知研究进行了全面优化。该研究提供了一种在不同脑区记录高信噪比信号的方法，有助于研究大脑内部的区域间信息通信。

dual-extracellular-recordings-mouse-hippocampus-prefrontal

Research

JoVE Journal

Neuroscience

Dual Extracellular Recordings in the Mouse Hippocampus and Prefrontal Cortex

759 次观看.  The University of Melbourne. 本研究提出了一种在小鼠海马体和前额叶皮层中执行双电极 LFP 记录的综合方案，以研究药物对这些区域的 LFP 特性的影响。该协议提供了一种低成本和超轻的脑信号记录设备，该设备针对小鼠的认知研究进行了全面优化。该研究提供了一种在不同脑区记录高信噪比信号的方法，有助于研究大脑内部的区域间信息通信。

视频: 作者聚焦：使用双 LFP 记录方案研究药物对小鼠大脑信号的影响

The technique of recording local field potentials (LFPs) is an electrophysiological method used to measure the electrical activity of localized neuronal populations. It serves as a crucial tool in cognitive research, particularly in brain regions like the hippocampus and prefrontal cortex. Dual LFP recordings between these areas are of particular interest as they allow the exploration of interregional signal communication. However, methods for performing these recordings are rarely described, and most commercial recording devices are either expensive or lack adaptability to accommodate specific experimental designs. This study presents a comprehensive protocol for performing dual-electrode LFP recordings in the mouse hippocampus and the prefrontal cortex to investigate the effects of antipsychotic drugs and potassium channel modulators on LFP properties in these areas. The technique enables the measurement of LFP properties, including power spectra within each brain region and coherence between the two. Additionally, a low-cost, custom-designed recording device has been developed for these experiments. In summary, this protocol provides a means to record signals with high signal-to-noise ratios in different brain regions, facilitating the investigation of interregional information communication within the brain.

This protocol outlines the use of a custom-designed recording device and electrodes to record local field potentials and investigate information flow in the mouse hippocampus and prefrontal cortex.