作者希望感谢以下组织: 中国国家自然科学基金 (31171018, 31171355), 广东省自然科学基金 (2013KJCX0054), 广东科学与技术部 (2014A030313418、2014A030313440) 和广州科技局 (201607010320)。

动物住房和所有动物实验都是按照华南师范大学动物研究伦理委员会批准的程序进行的, 根据国家研究所设立的动物保育指南。健康. 
 1. 准备解决方案 <ol> <li> 准备500毫升标准人工脑脊液 (ACSF), 其中包含我们发布的工作中所描述的组件 7 中列出的 表 1 。
	<ol> <li> 使用干净的玻璃烧杯与去离子水, 准备一个新的 ACSF 解决方案。用去离子水和干前的清洁铲子添加氯化钠, 氯化钾, NaH 2 PO 4 , NaHCO 3 , MgSO 4 , d-葡萄糖, 并添加 CaCl 2 后冒泡的解决方案与 95% O 2 /5% CO 2 混合物为〜20分钟 (详见表 1) 到500毫升的去离子水。搅拌直到完全溶解. </li>
		<li> 确保 ACSF 完全清除, 无需任何降水。然后将 pH 值调整到 7.2-7.4。气泡的气体混合物由 95% O 2 和 5% CO 2 组成, 用于 ~ 20 min. </li>
	</ol> </li> <li> 在 表 2 中描述了包含化学品的250毫升切片切割解决方案 7 。
	<ol> <li> 添加氯化钾, 氯化镁 2 , NaH 2 PO 4 , NaHCO 3 , 胆碱和 #183; Cl, d-葡萄糖, 并添加 CaCl 2 最后, 如1.1.1 中所示, 到250毫升的去离子水和溶解, 在1.1.1 和1.1.2 中描述. </li>
		<li> 冒泡后 95% O 2 /5% CO 2 , 将解决方案放在冷冻库中15-20 分钟, 以便切割解决方案变得 ice-cold 和部分冻结. 
		注意: 我们在1-2 月大的小鼠制作切片时使用这种切削液;该公式可能不同于2月以上的小鼠. </li>
		<li> 在无菌内毒素-游离等渗盐水 (0.9% 氯化钠) 中溶解, 制备 LPS 溶液。LPS 是管理腹腔 (0.5 毫克/千克), 并开始记录2小时后. </li>
	</ol> </li> </ol> 2。前额叶皮质切片的制备 <ol> <li> 从冰箱中取出切削液, 然后质, 以获得一层泥浆。以 95% O 2 /5% CO 2 将解决方案放在冰和气泡上。
	<li> 使用大而锋利的剪刀, 快速斩首描述的鼠标 9 , 并立即将头放入一个充满 ice-cold (0-4 和 #176; C) 切割液的烧杯中. </li>
	<li> 用细剪刀把头骨的顶端沿中线 caudal-to-nasal, 去掉侧面的颅骨部分。用细刮刀取出大脑, 然后滴入 ice-cold 切割液中. 
	注: 步骤 2.2-2.3 必须迅速完成 (理想情况下, #60; 1 分钟). </li>
	<li> 将大脑放在 9 cm 培养皿的盖子上, 装满冰块。用 ice-cold 切削液冲洗大脑。用刀片切断小脑和嗅球. </li>
	<li> 将氰胶水应用于 vibratome 的标本持有人。小心地将脑块放在胶水滴上, 侧一侧向上, 并立即浸入 ice-cold 切割液中. </li>
	<li> 将 vibratome 的刀片式服务器调整到15和 #176 的角度; 参照水平平面, 准备350和 #181; m 冠状脑切片 (叶片振动频率 = 85 赫兹, 速度 = 0.1 毫米/秒). </li>
	<li> 使用吸管, 将切片转移到充满 ACSF 的恢复腔中, 孵育1小时 (在 RT), 持续冒泡 95% O 2 /5% CO 2 。
</ol> 3。全细胞贴片记录 <ol> <li> 根据拉拔器操作手册中的特定指南, 将玻璃硼硅 micropipettes 用作记录电极或粉扑 micropipettes。对于记录电极, 尖端电阻是在范围4-6 米和 #8486;, 而粉扑 micropipettes 有尖端直径的范围2-5 和 #181; M. </li>
	<li> 添加 Na + 通道拦截器 (TTX, 1 和 #181; M), 以阻止快速 Na + 和 #160; 通道和因此行动电位, ACSF 和保持这个解决方案的恒定流速2-3 毫升/分钟在记录室, 由蠕动泵入房间和愿望。气泡的 ACSF 与 95% O 2 /5% CO 2 不断确保切片的可行性. </li>
	<li> 使用改良的巴斯德吸管将脑切片转入记录室, 其尖端被切割以适合切片大小。用带有平行尼龙线的铂片锚片覆盖切片, #8805; 2 毫米分开, 以保持在平台上的切片. </li>
	<li> 用内部解决方案填充记录微 7 ( 表 3 ), 用 GABA 在10和 #181; m、50和 #181; m 和100和 #181; m (溶解于 ACSF), 或 ACSF 作为车辆控制. </li>
	<li> 为了防止碎片堵塞, 在将记录电极浸入 ACSF 中之前, 使用1毫升注射器应用光正压。使用显微镜下的微 (4x 物镜), 定位记录电极和粉扑微, 使提示出现在显示器的视频图像的中心 ( 图 1 a ). </li>
	<li> 调整显微镜焦距 (40x 物镜), 同时逐渐降低粉扑微, 并将其置于记录神经元的45和 #176 的角度;。保持微和20-40 和 #181 之间记录的神经元之间的距离; m ( 图 1 B )。慢慢地和小心地接近神经元与记录电极, 然后释放正压。通过连接到电极托架的油管上的微弱和短暂的吸力来制造一个千兆欧姆的密封. </li>
	<li> 保持0毫伏的电压。在千兆欧姆密封形成后, 手动或自动补偿快、慢的电容。然后应用一个简短的和强吸力通过上述油管进入全细胞模式. </li>
	<li> 在电压钳模式下记录 eIPSC。使用 Picospritzer 控制的低气体压力 (氮气, 4-6 psi) 到粉扑微采用主8电压步进发生器提供单或配对 GABA 粉扑 ( 图 2 ). </li>
	<li> 更改粉扑持续时间以获得最佳的 eIPSC 结果 ( 图 3 ) 并测量 LPS 诱发的抑郁症模型 ( 图 4 ) 中的 eIPSC. </li>
</ol>

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作者没有什么可透露的。

粉扑应用广泛用于评价突触后受体功能3,4,7, 但在每个实验中都需要精确的控制。我们在这里描述了一个涉及全细胞贴片钳夹的过程, 它显示了 GABA-粉扑诱导的前额皮质脑切片中的干细胞 (即 eIPSCs)。记录电极的电阻约为5ω, 而粉扑 micropipettes 的尖端直径约为2-5 µm. 粉扑压力介于 4-6 psi 之间: 这一范围是至关重要的, 因为较高的压?...

膜片钳技术是研究神经元电信号的主要工具, 在二十世纪七十年代1,2中得到了发展。这项技术的一个主要优点是它提供了有关特定治疗 (例如, 药理学) 如何能够实时改变神经元功能或通道的知识3。脑切片全细胞记录中神经元功能的药理学评价需要应用药物, 如激动剂或特定受体的拮抗药, 来记录神经元。此方法允许识别在应用特定药物后发生的神经元改变, 从而更好地理解神经元的生理和病理特性4。虽然药理学管理可以通过灌注5或粉扑6进行, 后者是优势技术。特别是: (i) 粉扑应用迅速增加了在记录的神经元周围的药物浓度到一个水平, 使膜受体的脱敏被阻止;(ii) 药物膨化量极低, 因此对沐浴液的影响不大, 因而减少了被管理的化学药品对脑切片的不良影响;(iii) 粉扑协议可以设定和保存, 使实验非常精确地重现;(iv) 粉扑的应用代表了激动剂/拮抗药的经济用途, 特别是在这种试剂昂贵或难以获得的情况下。
在这里, 我们将专注于记录在急性制备的脑切片中, 由 GABA 引起的全细胞电流, 这种制备具有相对保存完好的脑回路的优点。我们如何进行粉扑诱导的抑制电流7将在本文中介绍。通过使用铯 (Cs+) 的内部解决方案, 并持有 0 mV 的神经元, 我们将引入 GABA-粉扑诱发抑制突触后电流 (eIPSCs) 与适当的技术细节。应用脂多糖 (lps) 注射液诱发的小鼠抑郁症模型, 结果表明, 与汽车控制相比, lps 注射的小鼠 eIPSC 振幅明显降低.我们的意图是, 这篇文章应该显示如何粉扑技术是广泛适用于研究, 以评估的影响, 任何化学物质, 化合物或药物的神经元活动的脑切片。

<table><tbody><tr><td>Glass Borosilicate micropipettes</td><td>Shutter Instruments</td><td>BF150-86-10</td><td>1.50 mm outer diameter; 0.86 mm inner diameter</td></tr><tr><td>Micropipette Puller</td><td>Shutter Instruments</td><td>MODEL P-97&amp;nbsp;</td><td>Flaming/Brow Micropipette Puller</td></tr><tr><td>Micromanipulators</td><td>Shutter Instruments</td><td>MP-285</td><td></td></tr><tr><td>Computer controlled Amplifier&amp;nbsp;&amp;nbsp;&amp;nbsp;</td><td>Molecular Devices</td><td>Multiclamp 700B</td><td></td></tr><tr><td>Digital Acquisition system&amp;nbsp;</td><td>Molecular Devices</td><td>Digidata 1440A</td><td></td></tr><tr><td>Imaging Camera</td><td>Nikon&amp;nbsp;</td><td>2115001</td><td>Inspection equipment</td></tr><tr><td>Microscopy&amp;nbsp;</td><td>Nikon&amp;nbsp;</td><td>Eclipse FN1&amp;nbsp;</td><td></td></tr><tr><td>Master 8</td><td>A.M.P.I.</td><td>Master-8 Pulse stimulator</td><td></td></tr><tr><td>Vibratome Slicer</td><td>Leica</td><td>VT 1000S</td><td></td></tr><tr><td>Razor blade</td><td>Gillette</td><td>74-S</td><td>FLYING EAGLE</td></tr><tr><td>Video monitor</td><td>Panasonic</td><td>WV-BM 1410</td><td></td></tr><tr><td>502 Glue</td><td>Deli</td><td>7146</td><td>Cyanoacrylate Glue</td></tr><tr><td>Peristaltic pump</td><td>Shanghai JIA PENG Corporation</td><td>BT100-1F</td><td></td></tr><tr><td>Video Camera</td><td>Olympus America Medical</td><td>OLY-150</td><td></td></tr><tr><td>Transfer Pipets</td><td>Biologix</td><td>30-0138A1</td><td></td></tr></tbody></table>

whole-cell currents induced by puff application of gaba in brain slices

在脑切片中进行全细胞膜膜片钳记录时, 常用的是药理学管理方法。在电生理记录中, 药物应用的最佳方法之一是粉扑技术, 可用于研究药理试剂对脑切片神经元活动的影响。粉扑应用的最大优点是在记录部位周围的药物浓度迅速增加, 从而防止了膜受体的脱敏。粉扑应用的成功使用需要注意以下因素: 药物的浓度、粉扑微的参数、粉扑微的尖端与记录的神经元之间的距离、持续时间和压力驱动粉扑 (磅每平方英寸, psi)。本文介绍了一个 step-by 步骤的过程, 记录全细胞电流诱导的膨化γ-丁酸 (GABA) 的一个神经元的前额皮质切片。值得注意的是, 同样的程序可以适用于其他脑区, 如海马和纹状体, 以及不同的准备, 如细胞培养。

这种粉扑技术可以让研究人员研究药物对特定神经元表面特殊受体的影响。在这篇文章中, 我们关注的电流介导 GABA 受体。图 1显示了粉扑和记录 micropipettes。为了消除对 ACSF 和蔗糖泡芙 (图 2A) 所产生的物理压力的记录神经元的任何影响, 将其用作控件。gaba 粉扑 (黑色) 引起的反应可以被 gaba 受体抑制剂阻断, 如 picro...

Watch this Scientific Journal Video about Whole-cell Currents Induced by Puff Application of GABA in Brain Slices at JoVE.com

Whole-cell Currents Induced by Puff Application of GABA in Brain Slices

粉扑诱导的全细胞电流在脑切片中的应用

我们描述的粉扑技术, 其中的药理试剂可以在整个细胞膜片钳记录, 并突出了各方面的特点, 这是至关重要的成功。

Pharmacological administration is commonly used when conducting whole-cell patch-clamp recording in brain slices. One of the best methods of drug ...

whole-cell-currents-induced-puff-application-gaba-brain

Research

JoVE Journal

Neuroscience

9.3K 次观看.  South China Normal University. 我们描述的粉扑技术, 其中的药理试剂可以在整个细胞膜片钳记录, 并突出了各方面的特点, 这是至关重要的成功。

视频: Whole-cell Currents Induced by Puff Application of GABA in Brain Slices

GABA-activated Single-channel and Tonic Currents in Rat Brain Slices

The GABAA channels are present in all neurons and are located both at synapses and outside of synapses where they generate phasic and tonic currents, respectively 4,5,6,7 The GABAA channel is a pentameric GABA-gated chloride channel. The channel subunits are grouped into 8 families (&alpha;1-6, &beta;1-3, &gamma;1-3, &delta;, &#949;, &theta;, &pi; and &rho;). Two alphas, two betas and one 3rd subunit form the functional channel 8. By combining studies of sub-type specific GABA-activated single-channel molecules with studies including all populations of GABAA channels in the neuron it becomes possible to understand the basic mechanism of neuronal inhibition and how it is modulated by pharmacological agents.
We use the patch-clamp technique 9,10 to study the functional properties of the GABAA channels in alive neurons in hippocampal brain slices and record the single-channel and whole-cell currents. We further examine how the channels are affected by different GABA concentrations, other drugs and intra and extracellular factors. For detailed theoretical and practical description of the patch-clamp method please see The Single-Channel Recordings edited by B Sakman and E Neher 10.

We use the patch-clamp technique to measure GABA-activated single-channel currents (GABAA channels, GABAA receptors) and the synaptic and tonic currents they generate in neurons. Activation of the channels decreases neuronal excitability in health and disease 1,2,3,4.

在大鼠脑片的单通道和补品GABA激活电流

The GABAA channels are present in all neurons and are located both at synapses and outside of synapses where they generate phasic and tonic currents, ...

科研

神经科学

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 ...

Slice It Hot: Acute Adult Brain Slicing in Physiological Temperature

Here we present a protocol for preparation of acute brain slices. This procedure is a critical element for electrophysiological patch-clamp experiments that largely determines the quality of results. It has been shown that omitting the cooling step during cutting procedure is beneficial in obtaining healthy slices and cells, especially when dealing with highly myelinated brain structures from mature animals. Even though the precise mechanism whereby elevated temperature supports neural health can only be speculated upon, it stands to reason that, whenever possible, the temperature in which the slicing is performed should be close to physiological conditions to prevent temperature related artifacts. Another important advantage of this method is the simplicity of the procedure and therefore the short preparation time. In the demonstrated method adult mice are used but the same procedure can be applied with younger mice as well as rats. Also, the following patch clamp experiment is performed on horizontal cerebellar slices, but the same procedure can also be used in other planes as well as other posterior areas of the brain.

In this paper we show a method for preparing acute brain slices in physiological temperature, using a conventional physiological solution without special modifications for the cutting (such as adding sucrose) and without intracardial perfusion of the animal before slice preparation.

切片热门:成人急性脑切片在生理温度

Here we present a protocol for preparation of acute brain slices. This procedure is a critical element for electrophysiological patch-clamp experiments ...

Whole-cell Patch-clamp Recordings in Brain Slices

Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the&#160;electrical properties of a substantial part of the neuron. In this configuration, the micropipette is in tight contact with the cell membrane, which prevents current leakage and thereby provides more accurate ionic current measurements than the previously used intracellular sharp electrode recording method. Classically, whole-cell recording can be performed on neurons in various types of preparations, including cell culture models, dissociated neurons, neurons in brain slices, and in intact anesthetized or awake animals. In summary, this technique has immensely contributed to the understanding of passive and active biophysical properties of excitable cells. A major advantage of this technique is that it provides information on how specific manipulations (e.g., pharmacological, experimenter-induced plasticity) may alter specific neuronal functions or channels in real-time. Additionally, significant opening of the plasma membrane allows the internal pipette solution to freely diffuse into the cytoplasm, providing means for introducing drugs, e.g., agonists or antagonists of specific intracellular proteins, and manipulating these targets without altering their functions in neighboring cells. This article will focus on whole-cell recording performed on neurons in brain slices,&#160;a preparation that has the advantage of recording neurons in relatively well preserved brain circuits, i.e., in a physiologically relevant context. In particular,&#160;when combined with appropriate pharmacology, this technique is a powerful tool allowing identification of specific neuroadaptations that occurred following any type of experiences, such as learning, exposure to drugs of abuse, and stress. In summary, whole-cell patch-clamp recordings in brain slices provide means to measure in ex vivo preparation long-lasting changes in neuronal functions that have developed in intact awake animals.

This protocol describes basic procedural steps for performing whole-cell patch-clamp recordings. This technique allows the study of&#160;the electrical behavior of neurons, and when performed in brain slices, allows the assessment of various neuronal functions from neurons that are still integrated in relatively well preserved brain circuits.

在脑片全细胞膜片钳记录

Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the&#160;electrical properties of a substantial part of the ...

Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices

Calcium (Ca2+) imaging is a powerful tool to investigate the spatiotemporal dynamics of intracellular Ca2+ signals in neuronal dendrites. Ca2+ fluctuations can occur through a variety of membrane and intracellular mechanisms and play a crucial role in the induction of synaptic plasticity and regulation of dendritic excitability. Hence, the ability to record different types of Ca2+ signals in dendritic branches is valuable for groups studying how dendrites integrate information. The advent of two-photon microscopy has made such studies significantly easier by solving the problems inherent to imaging in live tissue, such as light scattering and photodamage. Moreover, through combination of conventional electrophysiological techniques with two-photon Ca2+ imaging, it is possible to investigate local Ca2+ fluctuations in neuronal dendrites in parallel with recordings of synaptic activity in soma. Here, we describe how to use this method to study the dynamics of local Ca2+ transients (CaTs) in dendrites of GABAergic inhibitory interneurons. The method can be also applied to studying dendritic Ca2+ signaling in different neuronal types in acute brain slices.

We present a method combining whole-cell patch-clamp recordings and two-photon imaging to record Ca2+ transients in neuronal dendrites in acute brain slices.

脑切片神经元树突的双光子钙成像

Calcium (Ca2+) imaging is a powerful tool to investigate the spatiotemporal dynamics of intracellular Ca2+ signals in neuronal dendrites. Ca2+ ...

Methods for the Discovery of Novel Compounds Modulating a Gamma-Aminobutyric Acid Receptor Type A Neurotransmission

This manuscript presents a step-by-step protocol for screening compounds at gamma-aminobutyric acid type A (GABAA) receptors and its use towards the identification of novel molecules active in preclinical assays from an in vitro recombinant receptor to their pharmacological effects at native receptors in rodent brain slices. For compounds binding at the benzodiazepine site of the receptor, the first step is to set up a primary screen that consists of developing radioligand binding assays on cell membranes expressing the major GABAA subtypes. Then, taking advantage of the heterologous expression of rodent and human GABAA receptors in Xenopus oocytes or HEK 293 cells, it is possible to explore, in electrophysiological assays, the physiological properties of the different receptor subtypes and the pharmacological properties of the identified compounds. The Xenopus oocyte system will be presented here, starting with the isolation of the oocytes and their microinjection with different mRNAs, up to the pharmacological characterization using two-electrode voltage clamps. Finally, recordings conducted in rodent brain slices will be described that are used as a secondary physiological test to assess the activity of molecules at their native receptors in a well-defined neuronal circuit. Extracellular recordings using population responses of multiple neurons are demonstrated together with the drug application.

Here, we present protocols to discover compounds active at GABAA receptors, from the binding to the physiology and pharmacology.

新化合物调制伽玛-丁酸受体 a 型神经传递的发现方法

This manuscript presents a step-by-step protocol for screening compounds at gamma-aminobutyric acid type A (GABAA) receptors and its use towards the ...

Generation and On-Demand Initiation of Acute Ictal Activity in Rodent and Human Tissue

Controlling seizures remains a challenging issue for the medical community. To make progress, researchers need a way to extensively study seizure dynamics and investigate its underlying mechanisms. Acute seizure models are convenient, offer the ability to perform electrophysiological recordings, and can generate a large volume of electrographic seizure-like (ictal) events. The promising findings from acute seizure models can then be advanced to chronic epilepsy models and clinical trials. Thus, studying seizures in acute models that faithfully replicate the electrographic and dynamical signatures of a clinical seizure will be essential for making clinically relevant findings. Studying ictal events in acute seizure models prepared from human tissue is also important for making findings that are clinically relevant. The key focus in this paper is on the cortical 4-AP model due to its versatility in generating ictal events in both in vivo and in vitro studies, as well as in both mouse and human tissue. The methods in this paper will also describe an alternative method of seizure induction using the Zero-Mg2+ model and provide a detailed overview of the advantages and limitations of the epileptiform-like activity generated in the different acute seizure models. Moreover, by taking advantage of commercially available optogenetic mouse strains, a brief (30 ms) light pulse can be used to trigger an ictal event identical to those occurring spontaneously. Similarly, 30 - 100 ms puffs of neurotransmitters (Gamma-Amino Butyric Acid or glutamate) can be applied to the human tissue to trigger ictal events that are identical to those occurring spontaneously. The ability to trigger ictal events on-demand in acute seizure models offers the newfound ability to observe the exact sequence of events that underlie seizure initiation dynamics and efficiently evaluate potential anti-seizure therapies.

Acute seizure models are important for studying the mechanisms underlying epileptiform events. Furthermore, the ability to generate epileptiform events on-demand provides a highly efficient method to study the exact sequence of events underlying their initiation. Here, we describe the acute 4-aminopyridine cortical seizure models established in mouse and human tissue.

啮齿类动物和人体组织急性 ictal 活性的产生及按需启动

Controlling seizures remains a challenging issue for the medical community. To make progress, researchers need a way to extensively study seizure dynamics ...

Optogenetic Activation of Afferent Pathways in Brain Slices and Modulation of Responses by Volatile Anesthetics

Anesthetics influence consciousness in part via their actions on thalamocortical circuits. However, the extent to which volatile anesthetics affect distinct cellular and network components of these circuits remains unclear. Ex vivo brain slices provide a means by which investigators may probe discrete components of complex networks and disentangle potential mechanisms underlying the effects of volatile anesthetics on evoked responses. To isolate potential cell type- and pathway-specific drug effects in brain slices, investigators must be able to independently activate afferent fiber pathways, identify non-overlapping populations of cells, and apply volatile anesthetics to the tissue in aqueous solution. In this protocol, methods to measure optogenetically-evoked responses to two independent afferent pathways to neocortex in ex vivo brain slices are described. Extracellular responses are recorded to assay network activity and targeted whole-cell patch clamp recordings are conducted in somatostatin- and parvalbumin-positive interneurons. Delivery of physiologically relevant concentrations of isoflurane via artificial cerebral spinal fluid to modulate cellular and network responses is described.

Ex vivo brain slices can be used to study the effects of volatile anesthetics on evoked responses to afferent inputs. Optogenetics are employed to independently activate thalamocortical and corticocortical afferents to non-primary neocortex, and synaptic and network responses are modulated with isoflurane.

脑切片中传入通路的光遗传学激活和挥发性麻醉剂对反应的调节

Anesthetics influence consciousness in part via their actions on thalamocortical circuits. However, the extent to which volatile anesthetics affect ...

Horizontal Hippocampal Slices of the Mouse Brain

The hippocampus is a highly organized structure in the brain that is a part of the limbic system and is involved in memory formation and consolidation as well as the manifestation of severe brain disorders, including Alzheimer&#8217;s disease and epilepsy. The hippocampus receives a high degree of intra- and inter-connectivity, securing a proper communication with internal and external brain structures. This connectivity is accomplished via different informational flows in the form of fiber pathways. Brain slices are a frequently used methodology when exploring neurophysiological functions of the hippocampus. Hippocampal brain slices can be used for several different applications, including electrophysiological recordings, light microscopic measurements as well as several molecular biological and histochemical techniques. Therefore, brain slices represent an ideal model system to assess protein functions, to investigate pathophysiological processes involved in neurological disorders as well as for drug discovery purposes.
There exist several different ways of slice preparations. Brain slice preparations with a vibratome allow a better preservation of the tissue structure and guarantee a sufficient oxygen supply during slicing, which present advantages over the traditional use of a tissue chopper. Moreover, different cutting planes can be applied for vibratome brain slice preparations. Here, a detailed protocol for a successful preparation of vibratome-cut horizontal hippocampal slices of mouse brains is provided. In contrast to other slice preparations, horizontal slicing allows to keep the fibers of the hippocampal input path (perforant path) in a fully intact state within a slice, which facilitates the investigation of entorhinal-hippocampal interactions. Here, we provide a thorough protocol for the dissection, extraction, and acute horizontal slicing of the murine brain, and discuss challenges and potential pitfalls of this technique. Finally, we will show some examples for the use of brain slices in further applications.

This article aims to describe a systematic protocol to obtain horizontal hippocampal brain slices in mice. The objective of this methodology is to preserve the integrity of hippocampal fiber pathways, such as the perforant path and the mossy fiber tract to assess dentate gyrus related neurological processes.

鼠脑水平海马片

The hippocampus is a highly organized structure in the brain that is a part of the limbic system and is involved in memory formation and consolidation as ...

Recording Whole-Cell Currents with GABA Puffing in a Mouse Brain Slice

Source: Feng, Y. et al., <a href="https://app.jove.com/v/56387">Whole-cell Currents Induced by Puff Application of GABA in Brain Slices.</a>&#160;J. Vis. Exp. (2017)
This video demonstrates the recording of whole-cell currents induced by gamma-aminobutyric acid, or GABA, in a mouse prefrontal cortical brain slice. Controlled delivery of GABA opens chloride channels in a postsynaptic neuron, generating inhibitory postsynaptic currents, or IPSCs. These IPSCs increase with higher GABA concentrations, reflecting GABA&#39;s inhibitory activity on synaptic transmission.

在小鼠脑切片中使用 GABA 膨化记录全细胞电流

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

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