Este trabalho foi financiado pelo investigador novas start-up fundos de Albert Einstein College of Medicine da Yeshiva University de RVS.

<ol>
	<li>Apps, R., Hawkes, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebellar+cortical+organization:+a+one-map+hypothesis.">Cerebellar cortical organization: a one-map hypothesis.</a> Nat. Rev. Neurosci. 10, 670-681 (2009).</li><li>Grishkat, H. L., Eisenman, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+the+spinocerebellar+projection+in+the+prenatal+mouse.">Development of the spinocerebellar projection in the prenatal mouse.</a> J. Comp. Neurol. 363, 93-108 (1995).</li><li>Mesulam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Tracing neural connections with horseradish peroxidase. , (1982).</li><li>Reeber, S. L., Sillitoe, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterned+expression+of+a+cocaine-+and+amphetamine+regulated+transcript+(CART)+peptide+reveals+complex+circuit+topography+in+the+rodent+cerebellar+cortex.">Patterned expression of a cocaine- and amphetamine regulated transcript (CART) peptide reveals complex circuit topography in the rodent cerebellar cortex.</a> Journal of Comparative Neurology. , (2011).</li><li>Reeber, S. L., Gebre, S. A., Sillitoe, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence+mapping+of+afferent+topography+in+three+dimensions.">Fluorescence mapping of afferent topography in three dimensions.</a> Brain. Struct. Funct. , (2011).</li><li>Sillitoe, R. V., Stephen, D., Lao, Z., Joyner, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engrailed+homeobox+genes+determine+the+organization+of+Purkinje+cell+sagittal+stripe+gene+expression+in+the+adult+cerebellum.">Engrailed homeobox genes determine the organization of Purkinje cell sagittal stripe gene expression in the adult cerebellum.</a> J. Neurosci. 28, 12150-12162 (2008).</li><li>Sillitoe, R. V., Vogel, M. W., Joyner, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engrailed+homeobox+genes+regulate+establishment+of+the+cerebellar+afferent+circuit+map.">Engrailed homeobox genes regulate establishment of the cerebellar afferent circuit map.</a> J. Neurosci. 30, 10015-10024 (2010).</li><li>Vig, J., Goldowitz, D., Steindler, D. A., Eisenman, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compartmentation+of+the+reeler+cerebellum:+segregation+and+overlap+of+spinocerebellar+and+secondary+vestibulocerebellar+fibers+and+their+target+cells.">Compartmentation of the reeler cerebellum: segregation and overlap of spinocerebellar and secondary vestibulocerebellar fibers and their target cells.</a> Neuroscience. 130, 735-744 (2005).</li><li>Vogel, M. W., Prittie, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Topographic+spinocerebellar+mossy+fiber+projections+are+maintained+in+the+lurcher+mutant.">Topographic spinocerebellar mossy fiber projections are maintained in the lurcher mutant.</a> J. Comp. Neurol. 343, 341-351 (1994).</li><li>Voogd, J., Broere, G., van Rossum, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+medio-lateral+distribution+of+the+spinocerebellar+projection+in+the+anterior+lobe+and+the+simple+lobule+in+the+cat+and+a+comparison+with+some+other+afferent+fibre+systems.">The medio-lateral distribution of the spinocerebellar projection in the anterior lobe and the simple lobule in the cat and a comparison with some other afferent fibre systems.</a> Psychiatr. Neurol. Neurochir. 72, 137-151 (1969).</li><li>Wu, H. S., Sugihara, I., Shinoda, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Projection+patterns+of+single+mossy+fibers+originating+from+the+lateral+reticular+nucleus+in+the+rat+cerebellar+cortex+and+nuclei.">Projection patterns of single mossy fibers originating from the lateral reticular nucleus in the rat cerebellar cortex and nuclei.</a> J. Comp. Neurol. 411, 97-118 (1999).</li></ol>

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Nós descrevemos os detalhes cirúrgicos e técnicos necessários para o sucesso rastreamento axonal e dendrite usando uma abordagem baseada em romance fluorescentes para rapidamente rotulagem projeções neurais no desenvolvimento e camundongos adultos. Utilizando-WGA Alexa mostramos como traçadores e marcadores podem ser usados ​​para analisar padrões topografia de circuito em alta resolução e em três dimensões. Traçadores muitos estão disponíveis para rastrear circuitos neuro...

<table border="1"><tbody><tr><td> Equipamento / reagentes </td><td> Modelo / número Catálogo </td><td> Companhia </td></tr><tr><td> Bead esterilizador </td><td> Modelo Steri 250 Cat. # 18000-45 </td><td> Multa Ferramentas Ciência </td></tr><tr><td> Cauterizador </td><td> Gato. # 18000-00 </td><td> Multa Ferramentas Ciência </td></tr><tr><td> Vidro borosilicato capilares </td><td> Gato. # 300056 </td><td> Harvard Apparatus </td></tr><tr><td> Vidro duplo estágio Micropipeta Puller </td><td> Modelo PC-001-10 </td><td> Narishige </td></tr><tr><td> Seringa micrométrica </td><td> Gato. # GS-1100 </td><td> Gilmont Instruments </td></tr><tr><td> Instrumento estereotáxica Pequenos Animais </td><td> Modelo 940-A </td><td> Instrumentação Kopf </td></tr><tr><td> Manipulator eletrodo </td><td> Modelo 960 </td><td> Instrumentação Kopf </td></tr><tr><td> Vetcare câmara </td><td> Gato. #340508 </td><td> Harvard Apparatus </td></tr><tr><td> Almofada de aquecimento </td><td> Gato. # 341241 </td><td> Harvard Apparatus </td></tr><tr><td> Leica DFC360 FX câmera </td><td> DFC360 FX </td><td> Leica </td></tr><tr><td> Leica câmera DFC490 </td><td> DFC490 </td><td> Leica </td></tr><tr><td> Leica DM5500 microscópio </td><td> DM5500 </td><td> Leica </td></tr><tr><td> Leica DFC3000 FX câmera </td><td> DFC3000 FX </td><td> Leica </td></tr><tr><td> Leica MZ16 FA microscópio </td><td> MZ16 FA </td><td> Leica </td></tr><tr><td> Cy3 Filtro </td><td> Modelo # 11600231 </td><td> Leica </td></tr><tr><td> FITC Filtro </td><td> Modelo # 11513880 </td><td> Leica </td></tr><tr><td> A4 DAPI / filtro UV </td><td> Modelo # 11504162 </td><td> Leica </td></tr><tr><td> Aglutinina de gérmen de trigo, Alexa Fluor 488 conjugado </td><td> Gato. # W11261 </td><td> Invitrogen </td></tr><tr><td> Trigo germ aglutinina, Alexa Fluor 555 conjugado </td><td> Gato. # W32464 </td><td> Invitrogen </td></tr></tbody></table>

revealing neural circuit topography in multi-color

Circuitos neurais funcionais estão organizados em mapas topográficos. Para visualizar a arquitetura circuito complexo que nós desenvolvemos uma abordagem para a fiabilidade rótulo o padrão global de múltiplas projeções topográficos. O cerebelo é um modelo ideal para estudar o arranjo ordenado dos circuitos neurais. Por exemplo, a organização compartimental de espinocerebelar fibras musgosas provou ser um sistema indispensável para o estudo de padronização de fibras musgosas. Recentemente, mostrou que aglutinina de gérmen de trigo (WGA), conjugada com Alexa 555 e 488 podem ser usados ​​para rastreamento espinocerebelar projeções de fibras musgosas no desenvolvimento e camundongos adultos (Reeber et al. 2011). Encontramos três principais propriedades que tornam as ferramentas WGA-Alexa traçadores desejável para rotulagem projeções neural. Primeiro, fluoróforos Alexa são intensas e seu brilho permite imagens wholemount diretamente após rastreamento. Segundo, WGA-Alexa traçadores rótulo toda a trajetória de desenvolvimento neural e adultos Projections. Terceiro, WGA-Alexa traçadores são rapidamente transportados nas direções retrógrada e anterógrada. Aqui, descrevemos em detalhes como preparar os marcadores e outras ferramentas necessárias, como executar a cirurgia para rastreamento espinocerebelar ea melhor forma de projeções de imagem traçada em três dimensões. Em resumo, nós fornecemos um protocolo passo a passo de rastreamento que vai ser útil para decifrar a organização e conectividade de mapas funcionais não só no cerebelo, mas também no córtex, tronco cerebral e medula espinhal.

Watch this Scientific Journal Video about Revealing Neural Circuit Topography in Multi-Color at JoVE.com

Revealing Neural Circuit Topography in Multi-Color

Nós fornecemos um guia prático para entregar traçadores<em&gt; In vivo</em&gt; E usar a via espinocerebelar como um sistema modelo para demonstrar passos essenciais para a análise do circuito neuronal sucesso em camundongos. Descrevemos em detalhe o nosso protocolo versátil rastreamento que explora aglutinina de gérmen de trigo (WGA), conjugada com fluoróforos Alexa.

Revelando Topografia Circuito Neural em Multi-Color

Neural circuits are organized into functional topographic maps. In order to visualize complex circuit architecture we developed an approach to reliably ...

revealing-neural-circuit-topography-in-multi-color

Research

JoVE Journal

Neuroscience

14.9K visualizações.  Yeshiva University. Nós fornecemos um guia prático para entregar traçadores In vivo E usar a via espinocerebelar como um sistema modelo para demonstrar passos essenciais para a análise do circuito neuronal sucesso em camundongos. Descrevemos em detalhe o nosso protocolo versátil rastreamento que explora aglutinina de gérmen de trigo (WGA), conjugada com fluoróforos Alexa.

Vídeo: Revealing Neural Circuit Topography in Multi-Color

Dissection and Culture of Commissural Neurons from Embryonic Spinal Cord

Commissural neurons have been widely used to investigate the mechanisms underlying axon guidance during embryonic spinal cord development. The cell bodies of these neurons are located in the dorsal spinal cord and their axons follow stereotyped trajectories during embryonic development. Commissural axons initially project ventrally towards the floorplate. After crossing the midline, these axons turn anteriorly and project towards the brain. Each of these steps is regulated by the action of several guidance cues. Cultures highly enriched in commissural neurons are ideally suited for many experiments addressing the mechanisms of axon pathfinding, including turning assays, immunochemistry and biochemistry. Here, we describe a method to dissect and culture commissural neurons from E13 rat dorsal spinal cord. First, the spinal cord is isolated and dorsal strips are dissected out. The dorsal tissue is then dissociated into a cell suspension by trypsinization and mechanical disruption. Neurons are plated onto poly-L-lysine-coated glass coverslips or tissue-culture dishes. After 30 hours in vitro, most neurons have extended an axon. The purity of the culture (Yam et al. 2009), typically over 90%, can be assessed by immunolabeling with the commissural neuron markers DCC, LH2 and TAG1 (Helms and Johnson, 1998). This neuronal preparation is a useful tool for in vitro studies of the cellular and molecular mechanisms of commissural axon growth and guidance during spinal cord development.

This video demonstrates a method to dissect and culture commissural neurons from E13 rat dorsal spinal cord. Dissociated commissural neurons are useful to study the cellular and molecular mechanisms of axon growth and guidance.

Dissecção e Cultura de Neurônios da Medula Espinhal comissural embrionárias

Commissural neurons have been widely used to investigate the mechanisms underlying axon guidance during embryonic spinal cord development. The cell bodies ...

Neurociência

Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in rodents have shown a direct link between testosterone and aggressive behavior1 and folk wisdom adapts these findings to humans, suggesting that testosterone induces antisocial, egoistic or even aggressive behavior2. However, many researchers doubt a direct testosterone-aggression link in humans, arguing instead that testosterone is primarily involved in status-related behavior3,4. As a high status can also be achieved by aggressive and antisocial means it can be difficult to distinguish between anti-social and status seeking behavior.
We therefore set up an experimental environment, in which status can only be achieved by prosocial means. In a double-blind and placebo-controlled experiment, we administered a single sublingual dose of 0.5 mg of testosterone (with a hydroxypropyl-&beta;-cyclodextrin carrier) to 121 women and investigated their social interaction behavior in an economic bargaining paradigm. Real monetary incentives are at stake in this paradigm; every player A receives a certain amount of money and has to make an offer to another player B on how to share the money. If B accepts, she gets what was offered and player A keeps the rest. If B refuses the offer, nobody gets anything. A status seeking player A is expected to avoid being rejected by behaving in a prosocial way, i.e. by making higher offers.
The results show that if expectations about the hormone are controlled for, testosterone administration leads to a significant increase in fair bargaining offers compared to placebo. The role of expectations is reflected in the fact that subjects who report that they believe to have received testosterone make lower offers than those who say they believe that they were treated with a placebo. These findings suggest that the experimental economics approach is sensitive for detecting neurobiological effects as subtle as those achieved by administration of hormones. Moreover, the findings point towards the importance of both psychosocial as well as neuroendocrine factors in determining the influence of testosterone on human social behavior.

The procedure described in this protocol shows that testosterone administration and folk beliefs about testosterone may be associated with directly opposed social behaviors.

Combinando Behavioral Endocrinologia e Economia Experimental: Decisão da testosterona e Social Fazendo

Behavioral endocrinological research in humans as well as in animals suggests that testosterone plays a key role in social interactions. Studies in ...

Time-lapse Live Imaging of Clonally Related Neural Progenitor Cells in the Developing Zebrafish Forebrain

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To understand the behavior of neural progenitor cells in the complex in vivo environment, time-lapse live imaging of neural progenitor cells in an intact brain is critically required. In this video, we exploit the unique features of zebrafish embryos to visualize the development of forebrain neural progenitor cells in vivo. We use electroporation to genetically and sparsely label individual neural progenitor cells. Briefly, DNA constructs coding for fluorescent markers were injected into the forebrain ventricle of 22 hours post fertilization (hpf) zebrafish embryos and electric pulses were delivered immediately. Six hours later, the electroporated zebrafish embryos were mounted with low melting point agarose in glass bottom culture dishes. Fluorescently labeled neural progenitor cells were then imaged for 36hours with fixed intervals under a confocal microscope using water dipping objective lens. The present method provides a way to gain insights into the in vivo development of forebrain neural progenitor cells and can be applied to other parts of the central nervous system of the zebrafish embryo.

The present video demonstrates a method which takes advantage of the combination of electroporation and confocal microscopy to perform live imaging on individual neural progenitor cells in the developing zebrafish forebrain. In vivo analysis of the development of forebrain neural progenitor cells at a clonal level can be achieved in this way.

Lapso de tempo de imagens ao vivo de relação clonal células progenitoras neurais no desenvolvimento Zebrafish Encéfalo anterior

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To ...

Detection of Microregional Hypoxia in Mouse Cerebral Cortex by Two-photon Imaging of Endogenous NADH Fluorescence

The brain's ability to function at high levels of metabolic demand depends on continuous oxygen supply through blood flow and tissue oxygen diffusion. Here we present a visualized experimental and methodological protocol to directly visualize microregional tissue hypoxia and to infer perivascular oxygen gradients in the mouse cortex. It is based on the non-linear relationship between nicotinamide adenine dinucleotide (NADH) endogenous fluorescence intensity and oxygen partial pressure in the tissue, where observed tissue NADH fluorescence abruptly increases at tissue oxygen levels below 10 mmHg1. We use two-photon excitation at 740 nm which allows for concurrent excitation of intrinsic NADH tissue fluorescence and blood plasma contrasted with Texas-Red dextran. The advantages of this method over existing approaches include the following: it takes advantage of an intrinsic tissue signal and can be performed using standard two-photon in vivo imaging equipment; it permits continuous monitoring in the whole field of view with a depth resolution of ~50 &mu;m. We demonstrate that brain tissue areas furthest from cerebral blood vessels correspond to vulnerable watershed areas which are the first to become functionally hypoxic following a decline in vascular oxygen supply. This method allows one to image microregional cortical oxygenation and is therefore useful for examining the role of inadequate or restricted tissue oxygen supply in neurovascular diseases and stroke.

Here we describe a method to directly visualize microregional tissue hypoxia in the mouse cortex in vivo. It is based on concurrent two-photon imaging of nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation. This method is useful for high resolution analysis of tissue oxygen supply.

Detecção de hipóxia microrregional no Cortex Cerebral mouse por imagem de dois fótons de fluorescência endógena NADH

The brain's ability to function at high levels of metabolic demand depends on continuous oxygen supply through blood flow and tissue oxygen diffusion. ...

Wholemount Immunohistochemistry for Revealing Complex Brain Topography

The repeated and well-understood cellular architecture of the cerebellum make it an ideal model system for exploring brain topography. Underlying its relatively uniform cytoarchitecture is a complex array of parasagittal domains of gene and protein expression. The molecular compartmentalization of the cerebellum is mirrored by the anatomical and functional organization of afferent fibers. To fully appreciate the complexity of cerebellar organization we previously refined a wholemount staining approach for high throughput analysis of patterning defects in the mouse cerebellum. This protocol describes in detail the reagents, tools, and practical steps that are useful to successfully reveal protein expression patterns in the adult mouse cerebellum by using wholemount immunostaining. The steps highlighted here demonstrate the utility of this method using the expression of zebrinII/aldolaseC as an example of how the fine topography of the brain can be revealed in its native three-dimensional conformation. Also described are adaptations to the protocol that allow for the visualization of protein expression in afferent projections and large cerebella for comparative studies of molecular topography. To illustrate these applications, data from afferent staining of the rat cerebellum are included.

Neural circuits are topographically organized into functional compartments with specific molecular profiles. Here, we provide the practical and technical steps for revealing global brain topography using a versatile wholemount immunohistochemical staining approach. We demonstrate the utility of the method using the well-understood cytoarchitecture and circuitry of cerebellum.

Imuno-histoquímica para Topografia Wholemount cerebrais, Complexo

The repeated and well-understood cellular architecture of the cerebellum make it an ideal model system for exploring brain topography. Underlying its ...

Multi-unit Recording Methods to Characterize Neural Activity in the Locust (Schistocerca Americana) Olfactory Circuits

Detection and interpretation of olfactory cues are critical for the survival of many organisms. Remarkably, species across phyla have strikingly similar olfactory systems suggesting that the biological approach to chemical sensing has been optimized over evolutionary time1. In the insect olfactory system, odorants are transduced by olfactory receptor neurons (ORN) in the antenna, which convert chemical stimuli into trains of action potentials. Sensory input from the ORNs is then relayed to the antennal lobe (AL; a structure analogous to the vertebrate olfactory bulb). In the AL, neural representations for odors take the form of spatiotemporal firing patterns distributed across ensembles of principal neurons (PNs; also referred to as projection neurons)2,3. The AL output is subsequently processed by Kenyon cells (KCs) in the downstream mushroom body (MB), a structure associated with olfactory memory and learning4,5. Here, we present electrophysiological recording techniques to monitor odor-evoked neural responses in these olfactory circuits.
First, we present a single sensillum recording method to study odor-evoked responses at the level of populations of ORNs6,7. We discuss the use of saline filled sharpened glass pipettes as electrodes to extracellularly monitor ORN responses. Next, we present a method to extracellularly monitor PN responses using a commercial 16-channel electrode3. A similar approach using a custom-made 8-channel twisted wire tetrode is demonstrated for Kenyon cell recordings8. We provide details of our experimental setup and present representative recording traces for each of these techniques.

Multi-unit Recording Methods to Characterize Neural Activity in the Locust Schistocerca Americana Olfactory Circuits

We demonstrate variations of the extracellular multi-unit recording technique to characterize odor-evoked responses in the first three stages of the invertebrate olfactory pathway. These techniques can easily be adapted to examine ensemble activity in other neural systems as well.

Multi-unidade Métodos de gravação para caracterizar a atividade neural no Locust (<em&gt; Schistocerca Americana</em&gt;) Circuitos olfatórias

Detection and interpretation of olfactory cues are critical for the survival  of many organisms. Remarkably, species across phyla have strikingly similar ...

Neural Circuit Recording from an Intact Cockroach Nervous System

The cockroach ventral nerve cord preparation is a tractable system for neuroethology experiments, neural network modeling, and testing the physiological effects of insecticides. This article describes the scope of cockroach sensory modalities that can be used to assay how an insect nervous system responds to environmental perturbations. Emphasis here is on the escape behavior mediated by cerci to giant fiber transmission in Periplaneta americana. This in situ preparation requires only moderate dissecting skill and electrophysiological expertise to generate reproducible recordings of neuronal activity. Peptides or other chemical reagents can then be applied directly to the nervous system in solution with the physiological saline. Insecticides could also be administered prior to dissection and the escape circuit can serve as a proxy for the excitable state of the central nervous system. In this context the assays described herein would also be useful to researchers interested in limb regeneration and the evolution of nervous system development for which P. americana is an established model organism.

This article describes the cockroach ventral nerve cord dissection and extracellular recordings from the cercal nerve and connectives. Evoked responses are generated by electrical stimulation of the cercal nerve or direct mechanical stimulation of the cerci.

Neural Circuit gravação de um Sistema Nervoso Barata Intacta

The cockroach ventral nerve cord preparation is a tractable system for neuroethology experiments, neural network modeling, and testing the physiological ...

Neural Activity Propagation in an Unfolded Hippocampal Preparation with a Penetrating Micro-electrode Array

This protocol describes a method for preparing a new in vitro flat hippocampus preparation combined with a micro-machined array to map neural activity in the hippocampus. The transverse hippocampal slice preparation is the most common tissue preparation to study hippocampus electrophysiology. A longitudinal hippocampal slice was also developed in order to investigate longitudinal connections in the hippocampus. The intact mouse hippocampus can also be maintained in vitro because its thickness allows adequate oxygen diffusion. However, these three preparations do not provide direct access to neural propagation since some of the tissue is either missing or folded. The unfolded intact hippocampus provides both transverse and longitudinal connections in a flat configuration for direct access to the tissue to analyze the full extent of signal propagation in the hippocampus in vitro. In order to effectively monitor the neural activity from the cell layer, a custom made penetrating micro-electrode array (PMEA) was fabricated and applied to the unfolded hippocampus. The PMEA with 64 electrodes of 200 &#181;m in height could record neural activity deep inside the mouse hippocampus. The unique combination of an unfolded hippocampal preparation and the PMEA provides a new in-vitro tool to study the speed and direction of propagation of neural activity in the two-dimensional CA1-CA3 regions of the hippocampus with a high signal to noise ratio.

We have developed an in vitro unfolded hippocampus which preserves CA1-CA3 array of neurons. Combined with the penetrating micro-electrode array, neural activity can be monitored in both the longitudinal and transverse orientations. This method provides advantages over hippocampal slice preparations as the propagation in the entire hippocampus can be recorded simultaneously.

Neural Activity Propagação em uma Unfolded Hippocampal Preparação com um penetrante Micro-eletrodo Matriz

This protocol describes a method for preparing a new in vitro flat hippocampus preparation combined with a micro-machined array to map neural activity in ...

Time-dependent Increase in the Network Response to the Stimulation of Neuronal Cell Cultures on Micro-electrode Arrays

Micro-electrode arrays (MEAs) can be used to investigate drug toxicity, design paradigms for next-generation personalized medicine, and study network dynamics in neuronal cultures. In contrast with more traditional methods, such as patch-clamping, which can only record activity from a single cell, MEAs can record simultaneously from multiple sites in a network, without requiring the arduous task of placing each electrode individually. Moreover, numerous control and stimulation configurations can be easily applied within the same experimental setup, allowing for a broad range of dynamics to be explored. One of the key dynamics of interest in these in vitro studies has been the extent to which cultured networks display properties indicative of learning. Mouse neuronal cells cultured on MEAs display an increase in response following training induced by electrical stimulation. This protocol demonstrates how to culture neuronal cells on MEAs; successfully record from over 95% of the plated dishes; establish a protocol to train the networks to respond to patterns of stimulation; and sort, plot, and interpret the results from such experiments. The use of a proprietary system for stimulating and recording neuronal cultures is demonstrated. Software packages are also used to sort neuronal units. A custom-designed graphical user interface is used to visualize post-stimulus time histograms, inter-burst intervals, and burst duration, as well as to compare the cellular response to stimulation before and after a training protocol. Finally, representative results and future directions of this research effort are discussed.

Mouse neuronal cells cultured on multi-electrode arrays display an increase in response following electrical stimulation. This protocol demonstrates how to culture neurons, how to record activity, and how to establish a protocol to train the networks to respond to patterns of stimulation.

Aumento Time-dependente na resposta da rede à estimulação de culturas de pilha neuronais em matrizes do micro-elétrodo

Micro-electrode arrays (MEAs) can be used to investigate drug toxicity, design paradigms for next-generation personalized medicine, and study network ...

Assaying Circuit Specific Regulation of Adult Hippocampal Neural Precursor Cells

Adult neurogenesis is a dynamic process by which newly activated neural stem cells (NSCs) in the subgranular zone (SGZ) of the dentate gyrus (DG) generate new neurons, which integrate into an existing neural circuit and contribute to specific hippocampal functions. Importantly, adult neurogenesis is highly susceptible to environmental stimuli, which allows for activity-dependent regulation of various cognitive functions. A vast range of neural circuits from various brain regions orchestrates these complex cognitive functions. It is therefore important to understand how specific neural circuits regulate adult neurogenesis. Here, we describe a protocol to manipulate neural circuit activity using designer receptor exclusively activated by designer drugs (DREADDs) technology that regulates NSCs and newborn progeny in rodents. This comprehensive protocol includes stereotaxic injection of viral particles, chemogenetic stimulation of specific neural circuits, thymidine analog administration, tissue processing, immunofluorescence labeling, confocal imaging, and imaging analysis of various stages of neural precursor cells. This protocol provides detailed instructions on antigen retrieval techniques used to visualize NSCs and their progeny and describes a simple, yet effective way to modulate brain circuits using clozapine N-oxide (CNO) or CNO-containing drinking water and DREADDs-expressing viruses. The strength of this protocol lies in its adaptability to study a diverse range of neural circuits that influence adult neurogenesis derived from NSCs.

The goal of this protocol is to describe an approach for analyzing behavior of adult neural stem/progenitor cells in response to chemogenetic manipulation of a specific local neural circuit.

Regulação específica do circuito de assaying de células precursoras neurais hipocampais adultas

Adult neurogenesis is a dynamic process by which newly activated neural stem cells (NSCs) in the subgranular zone (SGZ) of the dentate gyrus (DG) generate ...