eoe sub articles

EoE Sub Articles

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Animal anesthesia and surgery
<ol>
	<li>Weigh and anesthetize the mouse with your approved anesthesia regimen from your local animal care committee.</li>
	<li>Perform a tail or toe pinch with forceps to confirm deep anesthesia before surgery.</li>
	<li>Position the mouse in a stereotaxic apparatus and fix its head.</li>
	<li>Apply eye ointment on both eyes to keep them moist. Follow your local animal care guidelines regarding pre- and postoperative analgesia.</li>
	<li>Shave the hair using surgical clippers. Make a small incision (12-15 mm) in the middle of the exposed surgical area with scissors. Using forceps, gently pull the scalp away from the midline.</li>
	<li>Separate the skin gently and remove residual tissue. Clean the skull using hydrogen peroxide-coated cotton buds.</li>
	<li>Drill two small holes of radii 1.0-1.5 mm on both the skull&#39;s left and right sides to allow the recording microelectrodes to be inserted into the M2 regions under a stereomicroscope (Figure 1A). 
	NOTE: Stereotaxic locations of bilateral M2: 1.94 mm anterior to the bregma, 1.0 mm lateral to the midline, and 0.8-1.1 mm ventral to the dura.</li>
	<li>Remove the dura mater carefully with a tungsten needle.</li>
	<li>Pull glass borosilicate micropipettes (outer diameter: 1.0 mm) as recording microelectrodes with resistance of 1-2 M&#937;.</li>
	<li>Insert two separate recording microelectrodes filled with 0.5 M NaCl into the holes using mechanical micromanipulators (at 60&#176;, Figure 1B).</li>
</ol>
2. LFP recordings in bilateral M2 of mice
<ol>
	<li>Lower the left and right glass electrodes slowly into the appropriate coordinates of bilateral M2 (Figure 1C).</li>
	<li>For quality control, test the resistance of each electrode using the differential amplifier before capturing LFPs.</li>
	<li>Set the recording process at 0.1 Hz high-pass and 1,000 Hz low-pass with 1,000x amplification.</li>
	<li>Collect digitized raw LFP data of at least 60 s spontaneous activities in a stable state, with mice breathing evenly at a respiratory rate of 2 breaths per second under anesthesia.</li>
	<li>After recording, slowly raise the electrodes out of the brain, then euthanize the mice by fast cervical dislocation.</li>
	<li>Save the data and analyze it offline.</li>
</ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>AC/DC Differential Amplifier</td>
			<td>A-M Systems</td>
			<td>Model 3000</td>
			<td></td>
		</tr>
		<tr>
			<td>Analog Digital converter</td>
			<td>Cambridge Electronic Design Ltd.</td>
			<td>Micro1401</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass borosilicate micropipettes</td>
			<td>Nanjing spring teaching experimental equipment company</td>
			<td>161230</td>
			<td>Outer diameter: 1.0mm</td>
		</tr>
		<tr>
			<td>Microelectrode puller</td>
			<td>Narishige</td>
			<td>PC-10</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Guangzhou Chemical Reagent Factory</td>
			<td>7647-14-5</td>
			<td></td>
		</tr>
		<tr>
			<td>Pin microelectrode holder</td>
			<td>World Precision Instruments, INC.</td>
			<td>MEH3SW10</td>
			<td></td>
		</tr>
		<tr>
			<td>Spike2</td>
			<td>Cambridge Electronic Design Ltd.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stereomicroscope</td>
			<td>Zeiss</td>
			<td>435064-9020-000</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereotaxic apparatus</td>
			<td>RWD Life Science</td>
			<td>68045</td>
			<td></td>
		</tr>
		<tr>
			<td>Urethane</td>
			<td>Sigma-Aldrich</td>
			<td>94300</td>
			<td></td>
		</tr>
	</tbody>
</table>

recording of local field potential from both hemispheres of the mouse brain

Source: Chen, Y., et al. <a href="https://app.jove.com/v/59310">Evaluation of Hemisphere Lateralization with Bilateral Local Field Potential Recording in Secondary Motor Cortex of Mice.</a> J. Vis. Exp. (2019).
This video demonstrates in vivo recording of local field potential (LFP) from bilateral M2 areas of the mouse brain. An anesthetized mouse is secured and prepared for the procedure. To record LFPs, insert microelectrodes into the target coordinates of the bilateral M2 areas, which are responsible for complex motor movements.

<img alt="Figure 1" src="/files/ftp_upload/22759/22759_figure 1.jpg" /> 
Figure 1: Diagram of the simultaneous LFP recording procedure. (A) Stereotaxic mouse with skull exposed and dura mater removed for in vivo bilateral recording of LFPs in left and right M2. (B) Two glass microelectrodes in touch with the cortical surface in the hole drilled simultaneously. (C) Recording microelectrodes and Ag/AgCl wires as reference electrodes positioned at appropriate sites.

Recording of Local Field Potential from Both Hemispheres of the Mouse Brain

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

Begin with an anesthetized mouse with its head secured in a stereotactic frame.
Shave and sterilize the scalp.
Make an incision and remove the residual tissue to expose the skull.
Clean the skull with a disinfectant and drill holes at the target locations.
Remove the outer layer of the brain.
Insert microelectrodes filled with an ionic solution into the holes at a desired angle.
Lower both microelectrodes into the target coordinates of the brain.
Test the electrodes&#39; resistance and adjust the recording settings to ensure the reliable acquisition of local field potential or LFP data.
LFP reflects voltage changes resulting from the collective activity of many neurons within a small region.
Record LFPs from both hemispheres to compare the neural activity between them.

recording-local-field-potential-from-both-hemispheres-mouse

Nanyang Technological University

Research

JoVE Encyclopedia of Experiments

Neuroscience

Neurophysiology

Electrophysiology Techniques

126 visualizações. Fonte: Chen, Y., et al. Avaliação da Lateralização do Hemisfério com Registro de Potencial de Campo Local Bilateral no Córtex Motor Secundário de Camundongos. J. Vis. Exp. (2019). Este vídeo demonstra a gravação in vivo do potencial de campo local (LFP) de áreas M2 bilaterais do cérebro do camundongo. Um camundongo anestesiado é protegido e preparado para o procedimento. Para registrar LFPs, insira microeletrodos nas coordenadas-alvo das áreas M2 bilaterais, que são responsáveis...

Vídeo: Registro do potencial de campo local de ambos os hemisférios do cérebro do camundongo - Conceito

Acute In Vivo Electrophysiological Recordings of Local Field Potentials and Multi-unit Activity from the Hyperdirect Pathway in Anesthetized Rats

Converging evidence shows that many neuropsychiatric diseases should be understood as disorders of large-scale neuronal networks. To better understand the pathophysiological basis of these diseases, it is necessary to precisely characterize in which way the processing of information is disturbed between the different neuronal parts of the circuit. Using extracellular in vivo electrophysiological recordings, it is possible to accurately delineate neuronal activity within a neuronal network. The application of this method has several advantages over alternative techniques, e.g., functional magnetic resonance imaging and calcium imaging, as it allows a unique temporal and spatial resolution and does not rely on genetically engineered organisms. However, the use of extracellular in vivo recordings is limited since it is an invasive technique that cannot be universally applied. In this article, a simple and easy to use method is presented with which it is possible to simultaneously record extracellular potentials such as local field potentials and multiunit activity at multiple sites of a network. It is detailed how a precise targeting of subcortical nuclei can be achieved using a combination of stereotactic surgery and online analysis of multi-unit recordings. Thus, it is demonstrated, how a complete network such as the hyperdirect cortico-basal ganglia loop can be studied in anesthetized animals in vivo.

Acute In Vivo Electrophysiological Recordings of Local Field Potentials and Multi-unit Activity from the Hyperdirect Pathway in Anesthetized Rats

In this study, the methodology is presented on how to perform multi-site in vivo electrophysiological recordings from the hyperdirect pathway under urethane anesthesia.

Agudo<em&gt; In Vivo</em&gt; Gravações eletrofisiológicas de Potenciais de campo locais e atividade de múltiplas unidades a partir do caminho hiperdiretivo em ratos anestesiados

Converging evidence shows that many neuropsychiatric diseases should be understood as disorders of large-scale neuronal networks. To better understand the ...

JoVE Journal

Neurociência

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in adult mammalian animals remains elusive. In this study, we describe an experimental procedure for measuring calcium dynamics through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy. This method enables recordings and quantifications of neural activity in bilateral mouse brain regions one at a time in the same experiment for a prolonged period in vivo. Key aspects of this method, which can be completed within an hour, include minimally invasive surgery procedures for creating dual optical windows, and the use of 2P imaging. Although we only demonstrate the technique in the S1 area, the method can be applied to other regions of the living brain facilitating the elucidation of structural and functional complexities of brain neural networks.

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

We describe an experimental procedure for measuring neuronal activity through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy in vivo.

Imagem de atividade Neural no córtex somatossensorial primário usando Thy1-GCaMP6s de ratos transgênicos

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in ...

Non-Invasive Modulation and Robotic Mapping of Motor Cortex in the Developing Brain

Mapping the motor cortex with transcranial magnetic stimulation (TMS) has potential to interrogate motor cortex physiology and plasticity but carries unique challenges in children. Similarly, transcranial direct current stimulation (tDCS) can improve motor learning in adults but has only recently been applied to children. The use of tDCS and emerging techniques like high&#8211;definition tDCS (HD-tDCS) require special methodological considerations in the developing brain. Robotic TMS motor mapping may confer unique advantages for mapping, particularly in the developing brain. Here, we aim to provide a practical, standardized approach for two integrated methods capable of simultaneously exploring motor cortex modulation and motor maps in children. First, we describe a protocol for robotic TMS motor mapping. Individualized, MRI-navigated 12x12 grids centered on the motor cortex guide a robot to administer single-pulse TMS. Mean motor evoked potential (MEP) amplitudes per grid point are used to generate 3D motor maps of individual hand muscles with outcomes including map area, volume, and center of gravity. Tools to measure safety and tolerability of both methods are also included. Second, we describe the application of both tDCS and HD-tDCS to modulate the motor cortex and motor learning. An experimental training paradigm and sample results are described. These methods will advance the application of non-invasive brain stimulation in children.

We demonstrate protocols for the modulation (tDCS, HD-tDCS) and mapping (robotic TMS) of the motor cortex in children.

Modulação não invasiva e mapeamento robótico do córtex motor no cérebro em desenvolvimento

Mapping the motor cortex with transcranial magnetic stimulation (TMS) has potential to interrogate motor cortex physiology and plasticity but carries ...

Recording of Local Field Potential from Both Hemispheres of the Mouse Brain

Transcrição

Recording of Local Field Potential from Both Hemispheres of the Mouse Brain