这项工作得到了加拿大卫生研究与自然科学研究所的支持。

所有程序均按照麦吉尔大学动物保护委员会和加拿大动物保护委员会批准的议定书和准则进行。 急性海马体外制备注意:分离完整的海马制剂涉及三个主要步骤:（1）溶液和设备的制备，（2）海马的解剖和（3）建立产生内在θ振荡所需的快速灌注速率系统。在该方案中，及时执行手术 - 从解剖到记录 - 特别重要，因为分离的海马构成如此密集但精细的制剂，其保持体外结构的功能连接性需要非常小心。准备事先确保尽可能早地提供足够的灌注水平以最小化细胞d保持生理功能。 <ol><li> 基于蔗糖的人造脑脊液（aCSF）溶液 <ol><li>准备1X的蔗糖溶液用于解剖和解剖后孵育。将表1中列出的所有组分（CaCl 2除外）合并成1升去离子水，并在4℃下储存长达2周。 </li></ol></li><li> 标准aCSF解决方案 <ol><li>在电生理记录期间准备标准aCSF用于高流量灌注分离的海马。为了使浓缩（5X）的库存aCSF中，溶解在表2中列出的所有部件，除了氯化钙2，在2升的去离子水，并储存于4℃。 </li></ol></li><li> 准备设备 <ol><li>在开始解剖之前，用冰块塑料托盘（30 x 20 x 5 cm），碳链连接管线和three玻璃培养皿（10 x 2厘米）（ 见图1 ）。 </li><li>添加300mL的蔗糖溶液（1X股票）至500mL烧杯中，气泡将其与碳合（95％O 2，5％CO 2），并添加的Ca 2+ [1.2毫]。 </li><li>将60 mL该蔗糖溶液转移到玻璃培养皿中，并在室温下放置。将其余部分置于4°C冷冻箱中10 - 15分钟。 </li><li>在整个解剖过程中用碳水泡沫冰冷的蔗糖溶液。 </li><li>用蔗糖溶液（4℃）填充第二培养皿（冷藏室）并保持在冰上。 </li><li>将30mL冰冷的蔗糖溶液加入到50mL烧杯中。 </li></ol></li></ol> 2.全海马解剖注意:解剖分离的海马的方法基本上与原来22描述的方法相同，但是关于pe的附加细节和变化灌注速率和记录技术。 <ol><li> 脑解剖 <ol><li>麻醉小鼠（P20 - 35）在通风橱下用浸有1 mL加入到笼子中的异氟烷（100％）浸泡的小纸巾。 </li><li>斩断麻醉的小鼠，并迅速将头浸入冰冷的蔗糖溶液（50mL烧瓶中，约5秒）。转移到纸巾上。 </li><li>使用手术刀做一个内侧皮肤切口（尾部到流行），并推动两侧的皮肤暴露头颅。 </li><li>用小剪刀剪开颅骨，用铲子迅速提取大脑，并将其放入含冰冷蔗糖溶液的培养皿中。让大脑冷却1-2分钟。 </li><li>当大脑正在恢复时，将2-3毫升蔗糖溶液加到覆盖在冰上的Petri（夹层）培养皿上的透镜纸上。 </li></ol></li><li> 隔离海马 <ol><li>将大脑放置在解剖盘中，直立位置ñ。 </li><li>用剃刀刀片去除小脑和额叶皮质。将大脑沿中心面切成两半，并将两个隔离的半球返回到保持室。再允许1 - 2分钟恢复。 </li><li>将单个半透明的脑垂直放置在解剖盘上。 </li><li>旋转盘，直到中间结构面向观察者，并且隔膜复合体的嵌入轮廓可见为丘脑前面的薄的梨形层组织。 </li><li>将半透明的大脑与微球保持稳定，并将聚四氟乙烯（PTFE）涂抹的小铲的小端立即放置在隔膜区（尾部）的后面。 </li><li>将涂抹的刮刀插入隔膜下方，并向下移动尖端，直到达到解剖盘。切断头部连接隔膜区域的纤维。沿着隔膜的前边缘重复相同的操作，并切割连接到大脑前部的纤维。 </li><li>用铲子轻轻地将刚好在海马上方的皮质的内部保持在直立的位置，使用微球来小心地拉下丘脑，下丘脑和剩余的脑干核。使用刮刀切断并取出拉出的组织。 </li><li>将隔离的半球置于其侧面，并确定海马的轮廓。 </li><li>将涂抹的刮刀插入侧脑室，背侧海马的末端。 </li><li>握住刮刀与半透明大脑的中间平面水平对齐，并将其滑过心室壁的平滑轮廓，直到尖端尾端出现。 </li><li>将刮铲放在海马下面，轻轻按压到连接的纤维上，沿着海马与上覆皮层连接的内层。将该微球涂在该层的外侧，并与涂抹的刮刀滑动，穿过连接纤维别尔斯。 </li><li>要完成提取，旋转解剖盘，并将涂抹的刮刀插入腹侧海马下。用刮刀轻轻握住皮质褶皱的内侧，并使用针对微球的切片运动切断内嗅连接。 注意:通过将涂覆的刮刀放置在整个海马下，并从下面拉出剩余的脑组织，可以去除整个septooppocampal复合物。 </li><li>隔离完成后，将海马放在盘子上，加入一滴冰冷的蔗糖溶液以保持凉爽。仔细地剪除任何剩余的皮层和纤维，并通过轻轻地将剃刀刀片穿过穹窿，将海马与隔膜分开。 注意:如果从锥体细胞进行膜片钳记录（见第4.6节光代谢对照），则可以以45°角横向切割分离的海马，以暴露CA1的锥体层（"angl切割"准备），而不损害海马剩余部分中的本地网络电路。 </li><li>将制剂转移到室温蔗糖溶液中，使其恢复15-30分钟，然后转移到记录室。 </li></ol></li></ol> 3.设置快速灌注记录孤立的海马<ol><li>设置重力灌注系统，使得氧化aCSF以20-25mL / min的连续高速流入。 <ol><li>提前准备aCSF（1X）烧瓶，并在开始实验前至少15分钟将其浸入温热浴（〜30℃）。打开在线解决方案加热器系统（30°C）。 </li><li>在整个实验中使用与碳水化合物连接的水族泡沫器和管线对aCSF进行氧化，并在灌注开始之前加入CaCl 2 [2mM]。 </li><li>停止aCSF流动，并使用广泛的海马转移到记录室玻璃移液器的末端。让蔗糖饱和的制剂沉淀在底部。 </li><li>将准备物放在记录室的中心（与入口 - 出口轴线一致），CA1和SUB的光滑表面在顶部。在中隔和颞叶处稳定小重量的海马，并重新启动aCSF流。 </li></ol></li></ol> 4.孤立性海马中的电生理学<ol><li> 细胞外记录体外海马theta振荡 <ol><li>对于体外分离的海马的局部场电位（LFP）或单一单位活性的细胞外监测，使用填充有aCSF的玻璃微量吸管（1-3MΩ）。使用增益x1000的片钳钳位放大器记录低噪声交流耦合场电位信号，在线带通滤波0.1 - 500 Hz，采样率为5-20 kHz。 注意:本协议中使用的定制显微镜配备了低（2.5X）和高倍率（40X）目标，用于海马低放大视图，以及用于单细胞识别的红外视频显微镜和落射荧光。该系统的组件包括立式荧光显微镜，荧光过滤器立方体，模拟摄像机和具有成像软件的数字帧采集器，一个定位于其上的定制灌注腔室（ 图2A ，插图i）和用于神经元记录的高精度显微操作器光纤放置。 </li><li>使用安装在显微镜上的相机连接到计算机显示屏，以低放大倍数（2.5X）检查海马制剂，并快速检查是否没有底切或损坏外表面。沿着CA1的光滑表面，沿着对角线排列的alveus纤维应该是可见的（ 图2A ，插图ii）当透过光照射通过海马脓。 </li><li>使用低倍率的宽场物镜来观察孤立的海马和LFP电极在特定记录位置的位置。 注意: 图2A中示出了放置在不同记录位置的多个电极的分离的海马制剂的布局。 </li><li>将LFP电极放入浴中，直到其接触CA1区域的表面（alveus）。 注意:这通常在交流耦合记录中产生快速瞬变，类似于当电极与记录介质接触时会发生什么。在此步骤之后，音频监视器可用于收听LFP通道信号。 注意:早期的活动迹象通常只会在10 - 15分钟之后出现，因此重要的是不要进入准备阶段。如果在这段时间之后，LFP电极的表面仍然没有起作用，通过层次上的进一步向下延伸并定期暂停，看看在接近主要细胞层时是否有任何形式的活动出现。如果在进一步的5 - 10分钟后没有检测到任何东西，请小心地收回电极，并将其放置在同一区域的其他位置。 </li><li>通过金字塔层推进LFP电极。观察到细胞外刺激活性最初增加，因为检测到来自个体神经元（大多是金字塔形和抑制性筐细胞）的单次排出。进一步放下电极，注意当尖端穿过辐射线时，尖峰再次褪色。观察到，随着记录位置通过辐射降低，在θ频率范围（4 - 12 Hz）中清晰可见的网络振荡变得明显，并达到最大幅度（〜100 - 300μV）。 </li></ol></li><li> Theta振荡在一个单一的地区 <ol><li>为了测试穿过CA1区域的自发性θ振荡的空间特性，将尖端ofa参考LFP电极在中间CA1部位（沿着纵向的颞轴位于中间位置），并将其降低到如上所述的辐射状态。 </li><li>将第二个LFP电极放入CA1位点（距离第一个LFP为200 - 800μm间隔或时间），并观察CA1 theta振荡可以在相对较大的距离上同步。 </li></ol></li><li> Theta振荡跨层 <ol><li>为了测试跨越海马层的theta振荡的性质，在CA1辐射位点留下参考LFP电极。从地层上方开始，将第二个电极放入锥体细胞层，并通过辐射体。观察跨越锥体层的LFP信号（相对相反）的逐渐反转。 注意:有关这些类型活动的代表性示例，请参见图2B 。层流/深度剖面和电流源密度（CSD）分析的例子被示出在分离海马相位反转的位点先前已经23，24，25出版。 </li></ol></li><li> 完整海马中的伽玛振荡和θ-γ耦合 <ol><li>将场电极放置在CA1 / SUB边界处，并将其降低，直到其位于金字塔形和分子层之间的界面处。在这个水平上，可以记录显示具有相位锁定到局部θ节奏的振幅变化的清晰伽马振荡的场电位24 。调整缩放以观察theta-gamma耦合的慢时间尺度。注意，伽马脉冲串发生在两个不同的频带中，这可以通过对在慢（25-50Hz）和快速伽马（150-250Hz）范围内的正在进行的LFP信号的带通滤波来显示（参见图2C代表性滤波痕迹）。 </li></ol></li><li> 体外海马θ振荡期间的全细胞膜片钳记录 注意:在本协议的这一部分，目标是获得视觉上指导的全细胞膜片钳记录从分离的海马识别的中间神经元从表达荧光蛋白的转基因PV-TOM小鼠tdTomato，在PV启动子的控制下（对于更多细节见材料和参考文献26 ）。 <ol><li>使用低（2.5X）和高功率（40X）放大倍数的荧光视频显微镜来显示位于来自PV-TOM小鼠的海马制剂表面附近的tdTomato阳性中间神经元（ 图3 ）。注意，虽然PV-TOM神经元可以被成功地可视化并且通过阿尔卑斯（达到100μm）的斑块靶向，但是当用角切割技术制备海马时，也可以相对容易地达到非荧光锥体细胞（参见第2.2.14节注）。</li><li>在海马低放大视图下，在CA1 / SUB中放置LFP电极以监测θ振荡，同时准备膜片钳实验。 </li><li>切换到40倍放大倍数并将目标物体沉入目标区域;降低它直到顶层变得可见。操纵显微镜的位置，以确保从相对侧开启补片移液器的充分开放通道。 </li><li>在荧光显微镜下，选择荧光PV-TOM细胞，并用填充有标准细胞内溶液的补片移液管（2-3MΩ）接近。 </li><li>使用口器将轻度正压施加到移液管上，并在电极下降到电池上时监测电阻。当尖端遇到目标细胞时，移液管阻力增加，并且当正压力推在膜上时出现明显的凹坑。释放压力并检查当前的脉冲是否平整，因为密封开始形成。马上放大至超极化电位（-70 mV），一旦实现GΩ密封，就会通过移液管支架施加少量负压使细胞膜破裂。 </li><li>一旦进入全细胞配置，检查在自发性海马振荡期间鉴定的PV细胞的生理特性（ 图3B ）。 </li><li>观察到来自PV细胞的细胞内膜电位记录的特征在于快速刺激行为和与正在进行的CA1 /SUBθ节律同步的动作电位突发。 </li><li>切换到电压钳位并将细胞保持在不同的膜电位，以表征由内在节奏活动产生的兴奋性与抑制性突触电流之比。 图3A中显示了来自锥体细胞的膜片钳记录的实例用于比较。 </li></ol></li><li> 孤立性海马中的光合作用控制 </stroNG&gt; 注:对于海马网络活动的光遗传控制，涉及含PV-GABA能细胞的节奏活化的细胞类型特异性的策略在这里被用作这些细胞显示在所述分离海马25同步主要细胞群中发挥重要的作用。通过将PV-Cre小鼠系与组成型表达ChR2 Cre-dependent（Ai32）的小鼠杂交，从而产生PV-ChY小鼠，实现兴奋性通道视紫红质-2（ChR2）在PV细胞中的选择性表达。或者，可以将病毒载体构建体（ 例如 ，AAVdj-ChETA-eYFP）注射到PV-Cre或PV-TOM小鼠的海马中（P15-16）以驱动兴奋性视蛋白在CA1 / SUB中间神经元中的表达（ 图4A ）。 注意:此策略已在前面描述25 。 <ol><li>将LFP电极放置在CA1 / SUB区域，并在隔离的海马中贴附附近的锥体细胞在PV中间神经元中表达蓝光敏感兴奋性视蛋白ChR2的小鼠的安瓿。 </li><li>在海马制剂上方放置一个光纤导轨（直径0.2-1毫米），并将其置于记录区域上。使用来自LED光源的蓝光（473 nm）进行光生刺激，由光脉冲（10 - 20 ms，由晶体管晶体管逻辑信号触发）或在θ频率（4 - 12 Hz）传送的正弦波电压指令组成。 注意:定制的基于LED的光刺激组件已在其他地方描述25 。 </li><li>切换到电流钳位并表征自发θ振荡期间金字塔形的活动。 </li><li>启动刺激方案并记录光响应。观察记录的神经元中的场振荡和突触活动在光遗传刺激期间变得越来越同步，并且PV细胞的节奏起搏导致对频率的鲁棒控制θ振荡的强度和强度（ 图4 ）。 </li></ol></li></ol>

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II. The differential influence of drugs upon both the septal cell firing pattern and the hippocampus theta activity.</a> Electroencephalogr Clin Neurophysiol. 14, 212-219 (1962).</li><li>Mitchell, S. J., Ranck, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+theta+rhythm+in+medial+entorhinal+cortex+of+freely+moving+rats.">Generation of theta rhythm in medial entorhinal cortex of freely moving rats.</a> Brain Res. 189 (1), 49-66 (1980).</li><li>Alonso, A., Garcia-Austt, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuronal+sources+of+theta+rhythm+in+the+entorhinal+cortex+of+the+rat.+I.+Laminar+distribution+of+theta+field+potentials.">Neuronal sources of theta rhythm in the entorhinal cortex of the rat. I. Laminar distribution of theta field potentials.</a> Exp Brain Res. 67 (3), 493-501 (1987).</li><li>Vertes, R. P., Kocsis, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brainstem-diencephalo-septohippocampal+systems+controlling+the+theta+rhythm+of+the+hippocampus.">Brainstem-diencephalo-septohippocampal systems controlling the theta rhythm of the hippocampus.</a> Neuroscience. 81 (4), 893-926 (1997).</li><li>Bland, B. H., Colom, L. V., Konopacki, J., Roth, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracellular+records+of+carbachol-induced+theta+rhythm+in+hippocampal+slices.">Intracellular records of carbachol-induced theta rhythm in hippocampal slices.</a> Brain Res. 447 (2), 364-368 (1988).</li><li>Cobb, S. R., Buhl, E. H., Halasy, K., Paulsen, O., Somogyi, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synchronization+of+neuronal+activity+in+hippocampus+by+individual+GABAergic+interneurons.">Synchronization of neuronal activity in hippocampus by individual GABAergic interneurons.</a> Nature. 378 (6552), 75-78 (1995).</li><li>Williams, J. H., Kauer, 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=Properties+of+carbachol-induced+oscillatory+activity+in+rat+hippocampus.">Properties of carbachol-induced oscillatory activity in rat hippocampus.</a> J Neurophysiol. 78 (5), 2631-2640 (1997).</li><li>Chapman, C. A., Lacaille, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholinergic+induction+of+theta-frequency+oscillations+in+hippocampal+inhibitory+interneurons+and+pacing+of+pyramidal+cell+firing.">Cholinergic induction of theta-frequency oscillations in hippocampal inhibitory interneurons and pacing of pyramidal cell firing.</a> J Neurosci. 19 (19), 8637-8645 (1999).</li><li>Strata, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrinsic+oscillations+in+CA3+hippocampal+pyramids:+physiological+relevance+to+theta+rhythm+generation.">Intrinsic oscillations in CA3 hippocampal pyramids: physiological relevance to theta rhythm generation.</a> Hippocampus. 8 (6), 666-679 (1998).</li><li>Kocsis, B., Bragin, A., Buzsaki, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interdependence+of+multiple+theta+generators+in+the+hippocampus:+a+partial+coherence+analysis.">Interdependence of multiple theta generators in the hippocampus: a partial coherence analysis.</a> J Neurosci. 19 (14), 6200-6212 (1999).</li><li>Fellous, J. M., Sejnowski, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholinergic+induction+of+oscillations+in+the+hippocampal+slice+in+the+slow+(0.5-2+Hz),+theta+(5-12+Hz),+and+gamma+(35-70+Hz)+bands.">Cholinergic induction of oscillations in the hippocampal slice in the slow (0.5-2 Hz), theta (5-12 Hz), and gamma (35-70 Hz) bands.</a> Hippocampus. 10 (2), 187-197 (2000).</li><li>Gillies, M. 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=A+model+of+atropine-resistant+theta+oscillations+in+rat+hippocampal+area+CA1.">A model of atropine-resistant theta oscillations in rat hippocampal area CA1.</a> J Physiol. 543 (Pt 3), 779-793 (2002).</li><li>Gloveli, T., 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=Orthogonal+arrangement+of+rhythm-generating+microcircuits+in+the+hippocampus.">Orthogonal arrangement of rhythm-generating microcircuits in the hippocampus.</a> Proc Natl Acad Sci U S A. 102 (37), 13295-13300 (2005).</li><li>Konopacki, J., Eckersdorf, B., Kowalczyk, T., Golebiewski, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Firing+cell+repertoire+during+carbachol-induced+theta+rhythm+in+rat+hippocampal+formation+slices.">Firing cell repertoire during carbachol-induced theta rhythm in rat hippocampal formation slices.</a> Eur J Neurosci. 23 (7), 1811-1818 (2006).</li><li>Hajos, N., 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=Maintaining+network+activity+in+submerged+hippocampal+slices:+importance+of+oxygen+supply.">Maintaining network activity in submerged hippocampal slices: importance of oxygen supply.</a> Eur J Neurosci. 29 (2), 319-327 (2009).</li><li>Manseau, F., Goutagny, R., Danik, M., Williams, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+hippocamposeptal+pathway+generates+rhythmic+firing+of+GABAergic+neurons+in+the+medial+septum+and+diagonal+bands:+an+investigation+using+a+complete+septohippocampal+preparation+in+vitro.">The hippocamposeptal pathway generates rhythmic firing of GABAergic neurons in the medial septum and diagonal bands: an investigation using a complete septohippocampal preparation in vitro.</a> J Neurosci. 28 (15), 4096-4107 (2008).</li><li>Goutagny, R., Jackson, J., Williams, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-generated+theta+oscillations+in+the+hippocampus.">Self-generated theta oscillations in the hippocampus.</a> Nat Neurosci. 12 (12), 1491-1493 (2009).</li><li>Jackson, J., Goutagny, R., Williams, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+and+slow+gamma+rhythms+are+intrinsically+and+independently+generated+in+the+subiculum.">Fast and slow gamma rhythms are intrinsically and independently generated in the subiculum.</a> J Neurosci. 31 (34), 12104-12117 (2011).</li><li>Amilhon, B., 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=Parvalbumin+Interneurons+of+Hippocampus+Tune+Population+Activity+at+Theta+Frequency.">Parvalbumin Interneurons of Hippocampus Tune Population Activity at Theta Frequency.</a> Neuron. 86 (5), 1277-1289 (2015).</li><li>Huh, C. Y., 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=Excitatory+Inputs+Determine+Phase-Locking+Strength+and+Spike-Timing+of+CA1+Stratum+Oriens/Alveus+Parvalbumin+and+Somatostatin+Interneurons+during+Intrinsically+Generated+Hippocampal+Theta+Rhythm.">Excitatory Inputs Determine Phase-Locking Strength and Spike-Timing of CA1 Stratum Oriens/Alveus Parvalbumin and Somatostatin Interneurons during Intrinsically Generated Hippocampal Theta Rhythm.</a> J Neurosci. 36 (25), 6605-6622 (2016).</li><li>Gu, N., 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=NMDA-dependent+phase+synchronization+between+septal+and+temporal+CA3+hippocampal+networks.">NMDA-dependent phase synchronization between septal and temporal CA3 hippocampal networks.</a> J Neurosci. 33 (19), 8276-8287 (2013).</li><li>Jackson, 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=Reversal+of+theta+rhythm+flow+through+intact+hippocampal+circuits.">Reversal of theta rhythm flow through intact hippocampal circuits.</a> Nat Neurosci. 17 (10), 1362-1370 (2014).</li><li>Gonzalez-Burgos, G., Lewis, D. 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作者声明没有竞争的商业或经济利益。

虽然来自急性海马切片的电生理记录构成了体外标准技术，但是本文提出的方法与传统方法有很大不同。不同于其中特定细胞层在表面可见并且可以直接检查的薄片制剂，完整的海马制剂更类似于体内构型，其中电极在穿过单个层时下降到目标脑区域中。海马的完整性与局部神经元群体的功能连通性和性质一起保存。这提供了一个复杂而强大的工具，用于调查海马中的小型和大型网?...

海马THETA振荡（4 - 12赫兹）之间是在哺乳动物脑节律活动的最主要的形式，并且据信在认知功能中发挥关键作用，如中的情节记忆1，2，3时空信息和形成处理。虽然一些体内研究，突出THETA调制地方细胞具有空间导航和病变的研究，以及临床证据的关系，支持海马THETA振荡参与记忆形成4，5，6，相关联的机制视图伴随着海马theta振荡的产生尚未完全了解。早期体内研究表明，θ活性主要依赖于外在振荡器，特别是节奏输入从传入大脑结构，例如隔膜和内嗅皮层7，8，9，10。与海马神经元的属性一起海马神经网络的内部连通- -一种内在因素作用也假定的基于体外观察11，12，13，14，15，16，17，18。然而，除了少数标志性开发方法研究19，20，21，困难可以复制的简单体外切片准备生理现实群体活动长期以来，延迟了对海马和相关领域的内在能力进行更为详细的实验检查来自我产生θ振荡。 标准体外薄片实验设置的一个重要缺点是脑结构的3D细胞和突触组织通常受到损害。这意味着不能支持基于空间分布的细胞组件的许多形式的协调网络活动，范围从局部组（半径≤1mm）到遍及一个或多个脑区域（&gt; 1mm）的神经元群体。考虑到这些考虑，需要一种不同类型的方法来研究θ振荡如何在海马中出现并传播到相关的皮层和皮质下输出结构。 近年来，初步开展了"完整的海马"准备，以检查双向intera两个结构22和"分离的海马"制剂的随后演变ctions，已经揭示，在缺少外部节奏输入23海马自发发生固有THETA振荡。这些方法的价值在于初步的认识，即这些区域的整个功能结构必须被保留以便在体外作为θ节律发生器22 。

<table><tbody><tr><td>&lt;strong&gt;Reagents&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Sodium Chloride</td><td>Sigma Aldrich</td><td>S9625</td><td></td></tr><tr><td>Sucrose</td><td>Sigma Aldrich</td><td>S9378</td><td></td></tr><tr><td>Sodium Bicarbonate</td><td>Sigma Aldrich</td><td>S5761</td><td></td></tr><tr><td>NaH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt; - sodium phosphate monobasic</td><td>Sigma Aldrich</td><td>S8282</td><td></td></tr><tr><td>Magnesium sulfate</td><td>Sigma Aldrich</td><td>M7506</td><td></td></tr><tr><td>Potassium Chloride</td><td>Sigma Aldrich</td><td>P3911</td><td></td></tr><tr><td>D-(+)-Glucose</td><td>Sigma Aldrich</td><td>G7528</td><td></td></tr><tr><td>Calcium chloride dihydrate</td><td>Sigma Aldrich</td><td>C5080</td><td></td></tr><tr><td>Sodium Ascorbate</td><td>Sigma Aldrich</td><td>A7631-25G</td><td></td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Equipment&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Standard Dissecting Scissors</td><td>Fisher Scientific</td><td>08-951-25</td><td>brain extraction</td></tr><tr><td>Scalpel Handle #4, 14 cm</td><td>WPI</td><td>500237</td><td>brain extraction</td></tr><tr><td>Filter forceps, flat jaws, straight (11 cm)</td><td>WPI</td><td>500456</td><td>brain extraction</td></tr><tr><td>Paragon Stainless Steel Scalpel Blades #20</td><td>Ultident</td><td>02-90010-20</td><td>brain extraction</td></tr><tr><td>Fine Point Curved Dissecting Scissors</td><td>Thermo Fisher Scientific</td><td>711999</td><td>brain extraction</td></tr><tr><td>Teflon (PTFE) -coated thin spatula</td><td>VWR</td><td>82027-534</td><td>hippocampal preparation</td></tr><tr><td>Hayman Style Microspatula</td><td>Fisher Scientific</td><td>21-401-25A</td><td>hippocampal preparation</td></tr><tr><td>Lab spoon</td><td>Fisher Scientific</td><td>14-375-20</td><td>hippocampal preparation</td></tr><tr><td>Borosilicate Glass Pasteur Pipets</td><td>Fisher Scientific</td><td>13-678-20A</td><td>hippocampal preparation</td></tr><tr><td>Droper</td><td>Fisher Scientific</td><td></td><td>hippocampal preparation</td></tr><tr><td>Razor blades Single edged</td><td>VWR</td><td>55411-055</td><td>hippocampal preparation</td></tr><tr><td>Lens paper (4 x 6&quot;)</td><td>VWR</td><td>52846-001</td><td>hippocampal preparation</td></tr><tr><td>Glass petri dishes (100 x 20 mm)</td><td>VWR</td><td>25354-080</td><td>hippocampal preparation</td></tr><tr><td>Plastic tray for ice; size 30 x 20 x 5 cm</td><td>n.a.</td><td>n.a.</td><td>hippocampal preparation</td></tr><tr><td>Single Inline Solution Heater</td><td>Warner Instruments</td><td>SH-27B</td><td>perfusion system</td></tr><tr><td>Aquarium air stones for bubbling</td><td>n.a.</td><td>n.a.</td><td>perfusion system</td></tr><tr><td>Tygon E-3603 tubing (ID 1/16 OD 1/8)</td><td>Fisherbrand</td><td>14-171-129</td><td>perfusion system</td></tr><tr><td>Electric Skillet</td><td>Black &amp;amp; Decker</td><td>n.a.</td><td>perfusion system</td></tr><tr><td>95% O&lt;sub&gt;2&lt;/sub&gt;/5% CO&lt;sub&gt;2&lt;/sub&gt; gas mixture (carbogen)&amp;nbsp;</td><td>Vitalaire</td><td>SG466204A</td><td>perfusion system</td></tr><tr><td>Glass bottles/flasks (4 x 1 L)</td><td>n.a.</td><td>n.a.</td><td>perfusion system</td></tr><tr><td>Submerged recording Chamber</td><td>custom design (FM)</td><td>n.a.</td><td>Commercial alternative may be used</td></tr><tr><td>Glass pipettes (1.5/0.84 OD/ID (mm) )</td><td>WPI</td><td>1B150F-4</td><td>electrophysiology</td></tr><tr><td>Hum Bug 50/60 Hz Noise Eliminator</td><td>Quest Scientific</td><td>Q-Humbug</td><td>electrophysiology</td></tr><tr><td>Multiclamp 700B patch-clamp amplifier</td><td>Molecular devices</td><td>MULTICLAMP</td><td>electrophysiology</td></tr><tr><td>Multiclamp 700B Commander Program</td><td>Molecular devices</td><td>MULTICLAMP</td><td>electrophysiology</td></tr><tr><td>Digital/Analogue converter</td><td>Molecular devices</td><td>DDI440</td><td>electrophysiology</td></tr><tr><td>PCLAMP10</td><td>Molecular devices</td><td>PCLAMP10</td><td>electrophysiology</td></tr><tr><td>Vibration isolation table&amp;nbsp;</td><td>Newport</td><td>n.a.</td><td>electrophysiology</td></tr><tr><td>Micromanipulators (manually operated )</td><td>Siskiyou&amp;nbsp;</td><td>MX130</td><td>electrophysiology (LFP)</td></tr><tr><td>Micromanipulators (automated)</td><td>Siskiyou&amp;nbsp;</td><td>MC1000e</td><td>electrophysiology (patch)</td></tr><tr><td>Audio monitor&amp;nbsp;</td><td>A-M Systems</td><td>Model 3300</td><td>electrophysiology</td></tr><tr><td>Micropipette/Patch pipette puller</td><td>Sutter</td><td>P-97</td><td>electrophysiology</td></tr><tr><td>Custom-built upright fluorescence microscope</td><td>Siskiyou</td><td>n.a.</td><td>Imaging</td></tr><tr><td>Analogue video camera</td><td>COHU</td><td>4912-2000/0000</td><td>Imaging</td></tr><tr><td>Digital frame grabber with imaging software</td><td>EPIX, Inc</td><td>PIXCI-SV7</td><td>Imaging</td></tr><tr><td>Olympus 2.5X objective</td><td>Olympus</td><td>MPLFLN</td><td>Imaging</td></tr><tr><td>Olympus 40X water immersion objective</td><td>Olympus</td><td>UIS2 LUMPLFLN</td><td>Imaging</td></tr><tr><td>Custom-made Light-Emitting Diode (LED) system&amp;nbsp;</td><td>custom</td><td>n.a.</td><td>optogenetic stimulation (Amhilon et al., 2015)</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Animals&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>PV::Cre (KI) mice</td><td>Jackson Laboratory</td><td>stock number 008069</td><td>Allow&amp;nbsp; Cre-directed gene expression in PV interneurons</td></tr><tr><td>Constitutive-conditional Ai9 mice (R26-lox-stop-lox-tdTomato (KI))</td><td>Jackson Laboratory</td><td>stock number 007905</td><td>Express TdTomato following Cre-mediated recombination</td></tr><tr><td>Ai32 mice (R26-lox-stop-lox-ChR2(H134R)-EYFP</td><td>Jackson Laboratory</td><td>stock&lt;br/&gt; number 012569</td><td>Express the improved channelrhodopsin-2/EYFP fusion protein following exposure to Cre recombinase</td></tr><tr><td>PVChY mice</td><td>In house breeding</td><td>n.a.</td><td>Offspring obtained from cross-breeding the PV-Cre line with Ai32 mice (R26-lox-stop-lox-ChR2(H134R)-EYFP</td></tr></tbody></table>

tuning in the hippocampal theta band in vitro: methodologies for recording from the isolated rodent septohippocampal circuit

该方案概述了从孤立的整个海马，WT和转基因小鼠制备和记录的程序，以及近来对θ振荡研究的方法和应用的改进。提出了分离的海马制剂的简单表征，其中检查内部海马θ振荡器之间的关系以及玉米螟-1（CA1）和亚细胞（SUB）区域的锥体细胞和GABA能中间神经元的活性。总体而言，我们显示分离的海马能够在体外产生内在的θ振荡，海马内产生的节律性可以通过对小白蛋白阳性（PV）中间神经元的光诱导刺激进行精确的操纵。 体外分离的海马制剂提供了独特的机会，使用来自视觉识别的neu的同时场和细胞内膜片钳记录更好地了解θ节奏生成的机制。

<html>本节说明通过在体外研究小鼠分离的海马制剂中的 θ振荡可以获得的结果的实例。提取分离的海马的解剖程序如图1所示 。使用这种制备，可以在放置多个场电极期间检查内在θ振荡，记录整体活动和将突触输入同步到分离的海马的不同区域和层中的神经元群体（ 图2 ）。提出了同时进行的全细胞膜片钳和细胞...

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Tuning in the Hippocampal Theta Band In Vitro: Methodologies for Recording from the Isolated Rodent Septohippocampal Circuit

在这里，我们提出了从孤立的整个海马制剂记录节律神经元网络theta和γ振荡的协议。我们描述从海马提取到场，单元和全细胞膜片钳记录的细节以及θ节律的光起搏的实验步骤。

调整在海马Theta乐队<em&gt;体外</em&gt;:从孤立的啮齿动物皮下注射电路记录的方法

This protocol outlines the procedures for preparing and recording from the isolated whole hippocampus, of WT and transgenic mice, along with recent ...

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Universidad de Cartagena UDEC

Research

JoVE Journal

Neuroscience

Tuning in the Hippocampal Theta Band In Vitro: Methodologies for Recording from the Isolated Rodent Septohippocampal Circuit

9.7K 次观看.  McGill University. 在这里，我们提出了从孤立的整个海马制剂记录节律神经元网络theta和γ振荡的协议。我们描述从海马提取到场，单元和全细胞膜片钳记录的细节以及θ节律的光起搏的实验步骤。 

视频: Tuning in the Hippocampal Theta Band In Vitro: Methodologies for Recording from the Isolated Rodent Septohippocampal Circuit

Automatic Detection of Highly Organized Theta Oscillations in the Murine EEG

Theta activity is generated in the septohippocampal system and can be recorded using deep intrahippocampal electrodes and implantable electroencephalography (EEG) radiotelemetry or tether system approaches. Pharmacologically, hippocampal theta is heterogeneous (see dualistic theory) and can be differentiated into type I and type II theta. These individual EEG subtypes are related to specific cognitive and behavioral states, such as arousal, exploration, learning and memory, higher integrative functions, etc. In neurodegenerative diseases such as Alzheimer&#39;s, structural and functional alterations of the septohippocampal system can result in impaired theta activity/oscillations. A standard quantitative analysis of the hippocampal EEG includes a Fast-Fourier-Transformation (FFT)-based frequency analysis. However, this procedure does not provide details about theta activity in general and highly-organized theta oscillations in particular. In order to obtain detailed information on highly-organized theta oscillations in the hippocampus, we have developed a new analytical approach. This approach allows for time- and cost-effective quantification of the duration of highly-organized theta oscillations and their frequency characteristics.

Theta activity in the hippocampus is related to specific cognitive and behavioral stages. Here, we describe an analytical method to detect highly-organized theta oscillations within the hippocampus using a time-frequency (i.e., wavelet analysis)-based approach.

高度组织的Theta振荡在鼠脑的自动检测

Theta activity is generated in the septohippocampal system and can be recorded using deep intrahippocampal electrodes and implantable ...

科研

行为学

Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs through activation of their ion channels and neurotransmitter receptors, and process information in part through activity-dependent release of gliotransmitters. Furthermore, astrocytes constitute the main uptake system for glutamate, contribute to potassium spatial buffering, as well as to GABA clearance. These cells therefore constantly monitor synaptic activity, and are thereby sensitive indicators for alterations in synaptically-released glutamate, GABA and extracellular potassium levels. Additionally, alterations in astroglial uptake activity or buffering capacity can have severe effects on neuronal functions, and might be overlooked when characterizing physiopathological situations or knockout mice. Dual recording of neuronal and astroglial activities is therefore an important method to study alterations in synaptic strength associated to concomitant changes in astroglial uptake and buffering capacities. Here we describe how to prepare hippocampal slices, how to identify stratum radiatum astrocytes, and how to record simultaneously neuronal and astroglial electrophysiological responses. Furthermore, we describe how to isolate pharmacologically the synaptically-evoked astroglial currents.

The preparation of acute brain slices from isolated hippocampi, as well as the simultaneous electrophysiological recordings of astrocytes and neurons in stratum radiatum during stimulation of schaffer collaterals is described. The pharmacological isolation of astroglial potassium and glutamate transporter currents is demonstrated.

双突触诱发的星形胶质细胞和神经元的反应，在急性海马脑片电生理记录

Astrocytes form together with neurons tripartite synapses, where they integrate and modulate neuronal activity. Indeed, astrocytes sense neuronal inputs ...

神经科学

Improved Preparation and Preservation of Hippocampal Mouse Slices for a Very Stable and Reproducible Recording of Long-term Potentiation

Long-term potentiation (LTP) is a type of synaptic plasticity characterized by an increase in synaptic strength and believed to be involved in memory encoding. LTP elicited in the CA1 region of acute hippocampal slices has been extensively studied. However the molecular mechanisms underlying the maintenance phase of this phenomenon are still poorly understood. This could be partly due to the various experimental conditions used by different laboratories. Indeed, the maintenance phase of LTP is strongly dependent on external parameters like oxygenation, temperature and humidity. It is also dependent on internal parameters like orientation of the slicing plane and slice viability after dissection.
The optimization of all these parameters enables the induction of a very reproducible and very stable long-term potentiation. This methodology offers the possibility to further explore the molecular mechanisms involved in the stable increase in synaptic strength in hippocampal slices. It also highlights the importance of experimental conditions in in vitro investigation of neurophysiological phenomena.

This paper presents a complete methodology to prepare and preserve in vitro acute hippocampal slices from adult mice. This protocol allows the recording of very stable long-lasting long-term potentiation (LTP) for more than 8 hours with a success rate of 95%.

长时程增强一个非常稳定的和可重复的记录和保存海马鼠标片制备工艺的改进

Long-term potentiation (LTP) is a type of synaptic plasticity characterized by an increase in synaptic strength and believed to be involved in memory ...

Whole-cell Patch-clamp Recordings from Morphologically- and Neurochemically-identified Hippocampal Interneurons

GABAergic inhibitory interneurons play a central role within neuronal circuits of the brain. Interneurons comprise a small subset of the neuronal population (10-20%), but show a high level of physiological, morphological, and neurochemical heterogeneity, reflecting their diverse functions. Therefore, investigation of interneurons provides important insights into the organization principles and function of neuronal circuits. This, however, requires an integrated physiological and neuroanatomical approach for the selection and identification of individual interneuron types. Whole-cell patch-clamp recording from acute brain slices of transgenic animals, expressing fluorescent proteins under the promoters of interneuron-specific markers, provides an efficient method to target and electrophysiologically characterize intrinsic and synaptic properties of specific interneuron types. Combined with intracellular dye labeling, this approach can be extended with post-hoc morphological and immunocytochemical analysis, enabling systematic identification of recorded neurons. These methods can be tailored to suit a broad range of scientific questions regarding functional properties of diverse types of cortical neurons.

Cortical networks are controlled by a small, but diverse set of inhibitory interneurons. Functional investigation of interneurons therefore requires targeted recording and rigorous identification. Described here is a combined approach involving whole-cell recordings from single or synaptically-coupled pairs of neurons with intracellular labeling, post-hoc morphological and immunocytochemical analysis.

从Morphologically-和确定的Neurochemically海马的interneurons全细胞膜片钳记录

GABAergic inhibitory interneurons play a central role within neuronal circuits of the brain. Interneurons comprise a small subset of the neuronal ...

Optogenetic Entrainment of Hippocampal Theta Oscillations in Behaving Mice

Extensive data on relationships of neural network oscillations to behavior and organization of neuronal discharge across brain regions call for new tools to selectively manipulate brain rhythms. Here we describe an approach combining projection-specific optogenetics with extracellular electrophysiology for high-fidelity control of hippocampal theta oscillations (5-10 Hz) in behaving mice. The specificity of the optogenetic entrainment is achieved by targeting channelrhodopsin-2 (ChR2) to the GABAergic population of medial septal cells, crucially involved in the generation of hippocampal theta oscillations, and a local synchronized activation of a subset of inhibitory septal afferents in the hippocampus. The efficacy of the optogenetic rhythm control is verified by a simultaneous monitoring of the local field potential (LFP) across lamina of the CA1 area and/or of neuronal discharge. Using this readily implementable preparation we show efficacy of various optogenetic stimulation protocols for induction of theta oscillations and for the manipulation of their frequency and regularity. Finally, a combination of the theta rhythm control with projection-specific inhibition addresses the readout of particular aspects of the hippocampal synchronization by efferent regions.

We describe the use of optogenetics and electrophysiological recordings for selective manipulations of hippocampal theta oscillations (5-10 Hz) in behaving mice. The efficacy of the rhythm entrainment is monitored using local field potential. A combination of opto- and pharmacogenetic inhibition addresses the efferent readout of hippocampal synchronization.

Optogenetic 在行为小鼠海马θ振荡中的作用

Extensive data on relationships of neural network oscillations to behavior and organization of neuronal discharge across brain regions call for new tools ...

Recording and Modulation of Epileptiform Activity in Rodent Brain Slices Coupled to Microelectrode Arrays

Temporal lobe epilepsy (TLE) is the most common partial complex epileptic syndrome and the least responsive to medications. Deep brain stimulation (DBS) is a promising approach when pharmacological treatment fails or neurosurgery is not recommended. Acute brain slices coupled to microelectrode arrays (MEAs) represent a valuable tool to study neuronal network interactions and their modulation by electrical stimulation. As compared to conventional extracellular recording techniques, they provide the added advantages of a greater number of observation points and a known inter-electrode distance, which allow studying the propagation path and speed of electrophysiological signals. However, tissue oxygenation may be greatly impaired during MEA recording, requiring a high perfusion rate, which comes at the cost of decreased signal-to-noise ratio and higher oscillations in the experimental temperature. Electrical stimulation further stresses the brain tissue, making it difficult to pursue prolonged recording/stimulation epochs. Moreover, electrical modulation of brain slice activity needs to target specific structures/pathways within the brain slice, requiring that electrode mapping be easily and quickly performed live during the experiment. Here, we illustrate how to perform the recording and electrical modulation of 4-aminopyridine (4AP)-induced epileptiform activity in rodent brain slices using planar MEAs. We show that the brain tissue obtained from mice outperforms rat brain tissue and is thus better suited for MEA experiments. This protocol guarantees the generation and maintenance of a stable epileptiform pattern that faithfully reproduces the electrophysiological features observed with conventional field potential recording, persists for several hours, and outlasts sustained electrical stimulation for prolonged epochs. Tissue viability throughout the experiment is achieved thanks to the use of a small-volume custom recording chamber allowing for laminar flow and quick solution exchange even at low (1 mL/min) perfusion rates. Quick MEA mapping for real-time monitoring and selection of stimulating electrodes is performed by a custom graphic user interface (GUI).

We illustrate how to perform recording and electrical modulation of 4-aminopyridine-induced epileptiform activity in rodent brain slices using microelectrode arrays. A custom recording chamber maintains tissue viability throughout prolonged experimental sessions. Live electrode mapping and selection of stimulating pairs are performed by a custom graphical user interface.

鼠脑切片偶联微电极阵列癫痫活性的记录与调控

Temporal lobe epilepsy (TLE) is the most common partial complex epileptic syndrome and the least responsive to medications. Deep brain stimulation (DBS) ...

Recording Spatially Restricted Oscillations in the Hippocampus of Behaving Mice

The local field potential (LFP) emerges from ion movements across neural membranes. Since the voltage recorded by LFP electrodes reflects the summed electrical field of a large volume of brain tissue, extracting information about local activity is challenging. Studying neuronal microcircuits, however, requires a reliable distinction between truly local events and volume-conducted signals originating in distant brain areas. Current source density (CSD) analysis offers a solution for this problem by providing information about current sinks and sources in the vicinity of the electrodes. In brain areas with laminar cytoarchitecture such as the hippocampus, one-dimensional CSD can be obtained by estimating the second spatial derivative of the LFP. Here, we describe a method to record multilaminar LFPs using linear silicon probes implanted into the dorsal hippocampus. CSD traces are computed along individual shanks of the probe. This protocol thus describes a procedure to resolve spatially restricted neuronal network oscillations in the hippocampus of freely moving mice.

This protocol describes the recording of local field potentials with multi-shank linear silicon probes. Conversion of the signals using current source density analysis allows the reconstruction of local electrical activity in the mouse hippocampus. With this technique, spatially restricted brain oscillations can be studied in freely moving mice.

行为小鼠海马空间受限振荡的记录

The local field potential (LFP) emerges from ion movements across neural membranes. Since the voltage recorded by LFP electrodes reflects the summed ...

Selective Manipulation of Theta Oscillations in a Mouse Model

Source: Bender, F. et al., <a href="https://appjove.unicartagenaproxy.elogim.com/v/57349">Optogenetic Entrainment of Hippocampal Theta Oscillations in Behaving Mice.</a> J. Vis. Exp (2018)
This video demonstrates a protocol to modulate theta oscillations in a genetically engineered mouse model with light-sensitive ion channels in its GABAergic medial septum neurons. By delivering light pulses to the hippocampus, the protocol aims to synchronize neuronal activity and generate theta oscillations, which are recorded as local field potentials.

小鼠模型中 Theta 振荡的选择性作

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
PV-Cre ...

JoVE Encyclopedia of Experiments

Neurophysiology

Stimulation and Modulation Techniques

Optogenetic Control of Hippocampal Network Dynamics

Source: Manseau, F., et al. <a href="https://appjove.unicartagenaproxy.elogim.com/v/55851">Tuning in the Hippocampal Theta Band In Vitro: Methodologies for Recording from the Isolated Rodent Septohippocampal Circuit.</a> J. Vis. Exp. (2017)
This video demonstrates the method to use optogenetics to modulate hippocampal network dynamics by activating genetically modified light-sensitive interneurons in a mouse brain slice, enhancing theta oscillation synchronization and studying neural circuit behavior.

海马网络动力学的光遗传学控制

All procedures involving animal samples have been reviewed and approved by the appropriate animal ethical review committee.

	Optogenetic control in the ...

In Vitro Recording of Theta Oscillations in the Mouse Hippocampus

Source: Manseau, F., et.al. <a href="https://appjove.unicartagenaproxy.elogim.com/v/55851">Tuning in the Hippocampal Theta Band In Vitro: Methodologies for Recording from the Isolated Rodent Septohippocampal Circuit.</a> J. Vis. Exp. (2017).
This video demonstrates the recording of rhythmic neuronal network activity, also known as theta oscillations, in an isolated hippocampus. Electrodes are inserted into various layers and spatial positions to detect and analyze theta oscillations. This shows the unique neuronal compositions and the connectivity of the neuronal network across different layers of the hippocampus.

调整在海马Theta乐队

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