Este trabajo fue financiado por una subvención número H64.09.016 VIDI de la Organización Holandesa para la Investigación Científica (NWO) a la ACB. CPF agradece a la Dra. Silvina A. Fratantoni por sus comentarios críticos y correcciones en el manuscrito final. GMRDL / EMMM son apoyados por la Fundación de Tecnología STW holandés (12151 proyecto y 11350), que forma parte del Nuevo Orden Mundial, y que es financiado en parte por el Ministerio de Asuntos Económicos. Agradecemos a la Catalina Kitts y Peter Drent de Nikon Instruments Europe BV de asistencia y apoyo. HX fue apoyada por la Real Academia Holandesa de Artes y Ciencias (subvención 11CDP10) y WT recibió el apoyo de subvención a la Organización Holandesa para la Investigación Científica (subvención 820.02.006).

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SPIE 3568 Optical Biopsies and Microscopic Techniques III. , 185-196 (1999).</li><li>Karadagli&#402;&#225;, D., Wilson, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Image+formation+in+structured+illumination+wide-field+fluorescence+microscopy.">Image formation in structured illumination wide-field fluorescence microscopy.</a> Micron. 39, 808-818 (2008).</li><li>Schermelleh, L., 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=Subdiffraction+multicolor+imaging+of+the+nuclear+periphery+with+3D+structured+illumination+microscopy.">Subdiffraction multicolor imaging of the nuclear periphery with 3D structured illumination microscopy.</a> Science. 320, 1332-1336 (2008).</li><li>Gustafsson, M. 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H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput,+detailed,+cell-specific+neuroanatomy+of+dendritic+spines+using+microinjection+and+confocal+microscopy.">High-throughput, detailed, cell-specific neuroanatomy of dendritic spines using microinjection and confocal microscopy.</a> Nat Protoc. 6, 1391-1411 (2011).</li><li>Fitzsimons, C. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Knockdown+of+the+glucocorticoid+receptor+alters+functional+integration+of+newborn+neurons+in+the+adult+hippocampus+and+impairs+fear-motivated+behavior.">Knockdown of the glucocorticoid receptor alters functional integration of newborn neurons in the adult hippocampus and impairs fear-motivated behavior.</a> Mol Psychiatry. , (2012).</li><li>van Hooijdonk, L. 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Los autores no tienen nada que revelar.

En este artículo se describe un protocolo de trabajo para obtener imágenes de las espinas dendríticas de las neuronas del hipocampo de rata en cultivo primario in vitro utilizando SIM. El método de cultivo de neuronas del hipocampo primaria es una adaptación del método original descrito por Banker Kaech y 18. Las diferencias principales son el uso de medio Neurobasal/B27 cultura, lo que elimina el requisito de las culturas de alimentación astroglial, y la adición de la FUDR inhibidor mitótic...

Una espina dendrítica es una pequeña protuberancia de la membrana de la neurona. Esta estructura característica está especializada para recibir normalmente el aporte de una sola sinapsis y representa el área de contacto físico entre dos neuronas. La mayoría de las espinas dendríticas funcionalmente maduros consisten en una punta globular, jefe llamado, y un cuello delgado que conecta la cabeza con el árbol dendrítico. Sin embargo, las espinas no son estáticos y se mueven y cambian su morfología continuamente, incluso en el cerebro adulto 2 activa. Dentro de un período de 2 semanas de tiempo, cultivos de neuronas del hipocampo de rata primaria derivados de tarde tiempo postnatal embrionario o temprano desarrollan árboles dendríticos complejos con numerosas protuberancias de la membrana que evolucionan a partir filipodia pronto para estructuras de la columna vertebral como 3. Sobre la base de este comportamiento dinámico y otras características, se cree que las espinas dendríticas para proporcionar un sustrato anatómico para el almacenamiento de memoria y 4,5 transmisión sináptica. Dada ªe papel crítico que el tamaño de la espina dendrítica y la forma han en la función sináptica, es importante medir con precisión sus dimensiones. Espinas varían de alrededor de 200 a 2000 nanómetros de longitud y pueden ser identificados fácilmente por confocal de escaneo láser microscopía de fluorescencia. Sin embargo, las dimensiones de la columna vertebral que no sean de longitud están por debajo de la resolución de los sistemas ópticos convencionales &quot;, teóricamente fijado por la difracción en torno a 200 nanómetros 6. Estos poderes resolver son insuficientes para obtener imágenes de detalles más finos, tales como la anchura de los cuellos de la columna vertebral y la cabeza. Mucho trabajo se ha dedicado a resolver este problema y muchas técnicas relativamente nuevas de super-resolución de microscopía han proporcionado avances sustanciales. En particular, es posible conseguir una resolución más allá del límite clásico sin descartar ninguna emisión de luz mediante el uso de microscopía de iluminación estructurada lateralmente (SIM) en un campo amplio, microscopio confocal no 7-10. El uso de esta técnica en combinación con la no lineatécnicas de microscopía r, es teóricamente posible mejorar la resolución lateral del microscopio óptico por un factor de 11 sin límite. Sin embargo, en la mayoría de circunstancias experimentales, SIM permite superar el límite de resolución en un factor de dos 1. Otras técnicas de microscopía óptica super-resolución, tales como el agotamiento de emisión estimulada (STED) microscopía 12 y foto-activación de localización de microscopía (PALM) 12 se han aplicado a las imágenes de las espinas dendríticas. Los métodos basados ​​en localización como la palma requieren un gran número de imágenes en bruto para conseguir super-resolución y por lo tanto están limitados en velocidad. Por otro lado, STED puede conseguir una elevada velocidad de imagen, aunque en el recuento de fotones relativamente bajos y los pequeños campos de visión, que puede no ser el caso para SIM 13. En este artículo, el objetivo es proporcionar un protocolo de trabajo para obtener imágenes de las espinas dendríticas de las neuronas del hipocampo primaria de rata en cultivo in vitro </em&gt; usando SIM. El protocolo consiste en dos fases: una distinguibles uno inicial que consiste de establecimiento, el desarrollo, la transfección y la inmunohistoquímica de cultivos de neuronas primarias del hipocampo de rata y una fase tardía dedicado a la muestra de imágenes.

<table>
	<tbody>
		<tr>
			<td>Fine forceps</td>
			<td></td>
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			<td></td>
		</tr>
		<tr>
			<td>Big forceps</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fine scissor</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Big scissor</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Blunt spatula</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dissecting microscope with illumination</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Light microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>37 &#176;C water bath</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Laminar flow cell culture hood</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>High-temperature dry-oven</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bunsen burner</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture incubator (5% CO2, 37 &#176;C)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
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			<td></td>
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		</tr>
		<tr>
			<td>Microcentrifuge</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Orbital shaker</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon structured illumination microscope setup consisting of:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon Eclipse Ti research inverted microscope with Perfect Focus System</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon CFI Apo TIRF 100x oil objective lens (N.A. 1.49)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4 Coherent Sapphire Lasers (458, 488, 514 and 561 nm exitation wavelength)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>SIM Illuminator</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon Stage Controller</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>MCL Nano-Drive piezo controller</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon Intensilight C-HGFIE mercury lamp</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>SIM Microscope Enclosure temperature control</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Andor EM-CCD Camera iXon DU897</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PC with Microsoft Windows 7 Home Edition</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon&#8217;s NiS Elements 6.14 SIM software package</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nikon type A immersion oil</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

imaging dendritic spines of rat primary hippocampal neurons using structured illumination microscopy

Las espinas dendríticas son protuberancias que salen de la dendrita de una neurona y representan los objetivos primarios postsinápticos excitatorios de entradas en el cerebro. Los avances tecnológicos han identificado estas estructuras como elementos clave de la conectividad neuronal y la plasticidad sináptica. El análisis cuantitativo de la morfología de la columna vertebral utilizando microscopía de luz sigue siendo un problema esencial debido a las limitaciones técnicas asociadas con límite de refracción intrínseca de la luz. Las espinas dendríticas pueden identificarse fácilmente por confocal de escaneo láser microscopía de fluorescencia. Sin embargo, la medición de los cambios sutiles en la forma y tamaño de las espinas es difícil debido a las dimensiones de la columna vertebral que no sean de longitud son generalmente más pequeñas que la resolución óptica convencional fijada por resolución límite teórico de la microscopía de luz de 200 nm. Varias técnicas de resolución de súper desarrollados recientemente se han utilizado para imagen estructuras celulares más pequeños que los 200 nm, incluyendo las espinas dendríticas. Tstos técnicas se basan en operaciones de campo lejano clásicos y por lo tanto permiten el uso de los métodos existentes de preparación de muestras y para la imagen más allá de la superficie de una muestra. Descrito aquí es un protocolo de trabajo para aplicar la resolución estructurada de iluminación microscopía super (SIM) para la obtención de imágenes de las espinas dendríticas en cultivos de neuronas del hipocampo primaria. Posibles aplicaciones de SIM se solapan con las de microscopía confocal. Sin embargo, las dos técnicas presentan diferente aplicabilidad. SIM ofrece una resolución lateral efectiva más alta, mientras que la microscopía confocal, debido al uso de un agujero de alfiler física, logra una mejora de resolución a costa de la eliminación de fuera de la luz de enfoque. En este protocolo, las neuronas primarias se cultivan en cubreobjetos de vidrio utilizando un protocolo estándar, transfectadas con plásmidos de ADN que codifican proteínas fluorescentes y fotografiado usando SIM. Todo el protocolo descrito en el presente documento toma aproximadamente 2 semanas, porque las espinas dendríticas son imágenes después de 16-17 días in vitro, cuandodesarrollo dendrítico es óptima. Después de completar el protocolo, las espinas dendríticas pueden ser reconstruidos en 3D de la serie de SIM pilas de imágenes utilizando el software especializado.

Descrito aquí es un protocolo de trabajo estandarizado para obtener imágenes de las espinas dendríticas de las neuronas del hipocampo de rata primaria in vitro utilizando SIM. El flujo de trabajo de protocolo y sus pasos cruciales se muestran en la Figura 1. En general, el protocolo de toma aproximadamente 2 semanas de trabajo experimental separados en una primera fase de preparación de la muestra, incluyendo la cultura, el desarrollo y la transfección de las neuronas del hipocampo de rata...

Watch this Scientific Journal Video about Imaging Dendritic Spines of Rat Primary Hippocampal Neurons using Structured Illumination Microscopy at JoVE.com

Imaging Dendritic Spines of Rat Primary Hippocampal Neurons using Structured Illumination Microscopy

En este artículo se describe un protocolo de trabajo para obtener imágenes de las espinas dendríticas de las neuronas del hipocampo in vitro utilizando Estructurado Iluminación Microscopía (SIM). Super-resolución de la microscopía utilizando SIM ofrece una resolución de imagen de manera significativa más allá del límite de difracción de la luz en las tres dimensiones espaciales, lo que permite la obtención de imágenes de las espinas dendríticas individuales con detalles mejorados.

Imaging las espinas dendríticas de las neuronas del hipocampo de rata primaria utilizando Estructurado Iluminación Microscopía

Dendritic spines are protrusions emerging from the dendrite of a neuron and represent the primary postsynaptic targets of excitatory inputs in the brain. ...

imaging-dendritic-spines-rat-primary-hippocampal-neurons-using

Research

JoVE Journal

Neuroscience

15.7K vistas.  University of Amsterdam.  En este artículo se describe un protocolo de trabajo para obtener imágenes de las espinas dendríticas de las neuronas del hipocampo in vitro utilizando Estructurado Iluminación Microscopía (SIM). Super-resolución de la microscopía utilizando SIM ofrece una resolución de imagen de manera significativa más allá del límite de difracción de la luz en las tres dimensiones espaciales, lo que permite la obtención de imágenes de las espinas dendríticas in...

Video: Imaging Dendritic Spines of Rat Primary Hippocampal Neurons using Structured Illumination Microscopy

Nucleofection and Primary Culture of Embryonic Mouse Hippocampal and Cortical Neurons

Hippocampal and cortical neurons have been used extensively to study central nervous system (CNS) neuronal polarization, axon/dendrite outgrowth, and synapse formation and function. An advantage of culturing these neurons is that they readily polarize, forming distinctive axons and dendrites, on a two dimensional substrate at very low densities. This property has made them extremely useful for determining many aspects of neuronal development. Furthermore, by providing glial conditioning for these neurons they will continue to develop, forming functional synaptic connections and surviving for several months in culture. In this protocol we outline a technique to dissect, culture and transfect embryonic mouse hippocampal and cortical neurons. Transfection is accomplished by electroporating DNA into the neurons before plating via nucleofection. This protocol has the advantage of expressing fluorescently-tagged fusion proteins early in development (~4-8hrs after plating) to study the dynamics and function of proteins during polarization, axon outgrowth and branching. We have also discovered that this single transfection before plating maintains fluorescently-tagged fusion protein expression at levels appropriate for imaging throughout the lifetime of the neuron (&gt; 2 months in culture). Thus, this methodology is useful for studying protein localization and function throughout CNS development with little or no disruption of neuronal function.

This protocol outlines the steps required to dissect, transfect via electroporation and culture mouse hippocampal and cortical neurons. Short-term cultures may be used for studies of axon outgrowth and guidance, while long-term cultures can be used for studies of synaptogenesis and dendritic spine analysis.

Nucleofection y cultivos primarios de neuronas del hipocampo de embriones de ratón y corticales

Hippocampal and cortical neurons have been used extensively to study central nervous system (CNS) neuronal polarization, axon/dendrite outgrowth, and ...

Investigación

Neurociencias

Fluorescence Recovery After Photobleaching (FRAP) of Fluorescence Tagged Proteins in Dendritic Spines of Cultured Hippocampal Neurons

FRAP has been used to quantify the mobility of GFP-tagged proteins. Using a strong excitation laser, the fluorescence of a GFP-tagged protein is bleached in the region of interest. The fluorescence of the region recovers when the unbleached GFP-tagged protein from outside of the region diffuses into the region of interest. The mobility of the protein is then analyzed by measuring the fluorescence recovery rate. This technique could be used to characterize protein mobility and turnover rate.
In this study, we express the (enhanced green fluorescent protein) EGFP vector in cultured hippocampal neurons. Using the Zeiss 710 confocal microscope, we photobleach the fluorescence signal of the GFP protein in a single spine, and then take time lapse images to record the fluorescence recovery after photobleaching. Finally, we estimate the percentage of mobile and immobile fractions of the GFP in spines, by analyzing the imaging data using ImageJ and Graphpad softwares.
This FRAP protocol shows how to perform a basic FRAP experiment as well as how to analyze the data.

Fluorescence Recovery After Photobleaching FRAP of Fluorescence Tagged Proteins in Dendritic Spines of Cultured Hippocampal Neurons

FRAP has been used to quantify the mobility of Green Fluorescence Protein (GFP)-tagged proteins in cultured cells. We examined the mobile/immobile fractions of the GFP by analyzing the fluorescence recovery percentage after photobleaching. In this study, FRAP was performed at spines of hippocampal neurons.

La recuperación de fluorescencia después de photobleaching (FRAP) de fluorescencia de proteínas marcadas en las espinas dendríticas de las neuronas del hipocampo cultivadas

FRAP has been used to quantify the mobility of GFP-tagged proteins. Using a strong excitation laser, the fluorescence of a GFP-tagged protein is bleached ...

Voltage-sensitive Dye Recording from Axons, Dendrites and Dendritic Spines of Individual Neurons in Brain Slices

Understanding the biophysical properties and functional organization of single neurons and how they process information is fundamental for understanding how the brain works. The primary function of any nerve cell is to process electrical signals, usually from multiple sources. Electrical properties of neuronal processes are extraordinarily complex, dynamic, and, in the general case, impossible to predict in the absence of detailed measurements. To obtain such a measurement one would, ideally, like to be able to monitor, at multiple sites, subthreshold events as they travel from the sites of origin on neuronal processes and summate at particular locations to influence action potential initiation. This goal has not been achieved in any neuron due to technical limitations of measurements that employ electrodes. To overcome this drawback, it is highly desirable to complement the patch-electrode approach with imaging techniques that permit extensive parallel recordings from all parts of a neuron. Here, we describe such a technique - optical recording of membrane potential transients with organic voltage-sensitive dyes (Vm-imaging) - characterized by sub-millisecond and sub-micrometer resolution. Our method is based on pioneering work on voltage-sensitive molecular probes 2. Many aspects of the initial technology have been continuously improved over several decades 3, 5, 11. Additionally, previous work documented two essential characteristics of Vm-imaging. Firstly, fluorescence signals are linearly proportional to membrane potential over the entire physiological range (-100 mV to +100 mV; 10, 14, 16). Secondly, loading neurons with the voltage-sensitive dye used here (JPW 3028) does not have detectable pharmacological effects. The recorded broadening of the spike during dye loading is completely reversible 4, 7. Additionally, experimental evidence shows that it is possible to obtain a significant number (up to hundreds) of recordings prior to any detectable phototoxic effects 4, 6, 12, 13. At present, we take advantage of the superb brightness and stability of a laser light source at near-optimal wavelength to maximize the sensitivity of the Vm-imaging technique. The current sensitivity permits multiple site optical recordings of Vm transients from all parts of a neuron, including axons and axon collaterals, terminal dendritic branches, and individual dendritic spines. The acquired information on signal interactions can be analyzed quantitatively as well as directly visualized in the form of a movie.

An imaging technique for monitoring of membrane potential changes with sub-micrometer spatial and sub-millisecond temporal resolution is described. The technique, based on laser excitation of voltage-sensitive dyes, allows measurements of signals in axons and axon collaterals, terminal dendritic branches, and individual dendritic spines.

Sensibles al voltaje Dye grabación de axones, dendritas y espinas dendríticas de las neuronas individuales en rodajas de cerebro

Understanding the biophysical properties and functional organization of single neurons and how they process information is fundamental for understanding ...

Calcium Phosphate Transfection of Primary Hippocampal Neurons

Calcium phosphate precipitation is a convenient and economical method for transfection of cultured cells. With optimization, it is possible to use this method on hard-to-transfect cells like primary neurons. Here we describe our detailed protocol for calcium phosphate transfection of hippocampal neurons cocultured with astroglial cells.

Fosfato de Calcio La transfección de Primaria neuronas del hipocampo

Calcium phosphate precipitation is a convenient and economical method for transfection of cultured cells. With optimization, it is possible to use this ...

Two-Photon in vivo Imaging of Dendritic Spines in the Mouse Cortex Using a Thinned-skull Preparation

In the mammalian cortex, neurons form extremely complicated networks and exchange information at synapses. Changes in synaptic strength, as well as addition/removal of synapses, occur in an experience-dependent manner, providing the structural foundation of neuronal plasticity. As postsynaptic components of the most excitatory synapses in the cortex, dendritic spines are considered to be a good proxy of synapses. Taking advantages of mouse genetics and fluorescent labeling techniques, individual neurons and their synaptic structures can be labeled in the intact brain. Here we introduce a transcranial imaging protocol using two-photon laser scanning microscopy to follow fluorescently labeled postsynaptic dendritic spines over time in vivo. This protocol utilizes a thinned-skull preparation, which keeps the skull intact and avoids inflammatory effects caused by exposure of the meninges and the cortex. Therefore, images can be acquired immediately after surgery is performed. The experimental procedure can be performed repetitively over various time intervals ranging from hours to years. The application of this preparation can also be expanded to investigate different cortical regions and layers, as well as other cell types, under physiological and pathological conditions.

Two-Photon in vivo Imaging of Dendritic Spines in the Mouse Cortex Using a Thinned-skull Preparation

Time-lapse imaging in the living animal provides valuable information on structural reorganization in the intact brain. Here, we introduce a thinned-skull preparation that allows transcranial imaging of fluorescently labeled synaptic structures in the living mouse cortex by two-photon microscopy.

De dos fotones<em&gt; In vivo</em&gt; Imágenes de las espinas dendríticas en la corteza del ratón Usando un Diluido-cráneo Preparación

In the mammalian cortex, neurons form extremely complicated networks and exchange information at synapses. Changes in synaptic strength, as well as ...

Live Images of GLUT4 Protein Trafficking in Mouse Primary Hypothalamic Neurons Using Deconvolution Microscopy

Type 2 diabetes mellitus (T2DM) is a global health crisis which is characterized by insulin signaling impairment and chronic inflammation in peripheral tissues. The hypothalamus in the central nervous system (CNS) is the control center for energy and insulin signal response regulation. Chronic inflammation in peripheral tissues and imbalances of certain chemokines (such as CCL5, TNF&#945;, and IL-6) contribute to diabetes and obesity. However, the functional mechanism(s) connecting chemokines and hypothalamic insulin signal regulation still remain unclear.
In vitro primary neuron culture models are convenient and simple models which can be used to investigate insulin signal regulation in hypothalamic neurons. In this study, we introduced exogeneous GLUT4 protein conjugated with GFP (GFP-GLUT4) into primary hypothalamic neurons to track GLUT4 membrane translocation upon insulin stimulation. Time-lapse images of GFP-GLUT4 protein trafficking were recorded by deconvolution microscopy, which allowed users to generate high-speed, high-resolution images without damaging the neurons significantly while conducting the experiment. The contribution of CCR5 in insulin regulated GLUT4 translocation was observed in CCR5 deficient hypothalamic neurons, which were isolated and cultured from CCR5 knockout mice. Our results demonstrated that the GLUT4 membrane translocation efficiency was reduced in CCR5 deficient hypothalamic neurons after insulin stimulation.

This protocol describes a technique for observation of real-time Green Fluorescence Protein (GFP) tagged Glucose Transporter 4 (GLUT4) protein trafficking upon insulin stimulation and characterization of the biological role of CCR5 in the insulin&#8211;GLUT4 signaling pathway with Deconvolution Microscopy.

Imágenes en vivo de la proteína GLUT4 trata de ratón las neuronas hipotalámica primaria utilizando microscopía de deconvolución

Type 2 diabetes mellitus (T2DM) is a global health crisis which is characterized by insulin signaling impairment and chronic inflammation in peripheral ...

Generation of Neurospheres from Mixed Primary Hippocampal and Cortical Neurons Isolated from E14-E16 Sprague Dawley Rat Embryo

Primary neuron culture is an essential technique in the field of neuroscience. To gain deeper mechanistic insights into the brain, it is essential to have a robust in vitro model that can be exploited for various neurobiology studies. Though primary neuron cultures (i.e., long-term hippocampal cultures) have provided scientists with models, it does not yet represent the complexity of brain network completely. In the wake of these limitations, a new model has emerged using neurospheres, which bears a closer resemblance to the brain tissue. The present protocol describes the plating of high and low densities of mixed cortical and hippocampal neurons isolated from the embryo of embryonic day 14-16 Sprague Dawley rats. This allows for the generation of neurospheres and long-term primary neuron culture as two independent platforms to conduct further studies. This process is extremely simple and cost-effective, as it minimizes several steps and reagents previously deemed essential for neuron culture. This is a robust protocol with minimal requirements that can be performed with achievable results and further used for a diversity of studies related to neuroscience.

Presented here is a protocol for the spontaneous generation of neurospheres enriched in neural progenitor cells from high density plated neurons. During the same experiment, when neurons are plated at a lower density, the protocol also results in prolonged primary rat neuron cultures.

Generación de neuroesferas a partir de neuronas de hipocampo primario mixto y cortical esinas aisladas del e14-E16 Sprague Dawley Rat Embryo

Primary neuron culture is an essential technique in the field of neuroscience. To gain deeper mechanistic insights into the brain, it is essential to have ...

3D Modeling of Dendritic Spines with Synaptic Plasticity

Computational modeling of diffusion and reaction of chemical species in a three-dimensional (3D) geometry is a fundamental method to understand the mechanisms of synaptic plasticity in dendritic spines. In this protocol, the detailed 3D structure of the dendrites and dendritic spines is modeled with meshes on the software Blender with CellBlender. The synaptic and extrasynaptic regions are defined on the mesh. Next, the synaptic receptor and synaptic anchor molecules are defined with their diffusion constants. Finally, the chemical reactions between synaptic receptors and synaptic anchors are included and the computational model is solved numerically with the software MCell. This method describes the spatiotemporal path of every single molecule in a 3D geometrical structure. Thus, it is very useful to study the trafficking of synaptic receptors in and out of the dendritic spines during the occurrence of synaptic plasticity. A limitation of this method is that the high number of molecules slows the speed of the simulations. Modeling of dendritic spines with this method allows the study of homosynaptic potentiation and depression within single spines and heterosynaptic plasticity between neighbor dendritic spines.

The protocol develops a three-dimensional (3D) model of a dendritic segment with dendritic spines for modeling synaptic plasticity. The constructed mesh can be used for computational modeling of AMPA receptor trafficking in the long-term synaptic plasticity using the software program Blender with CellBlender and MCell.

Modelado 3D de espinas dendríticas con plasticidad sináptica

Computational modeling of diffusion and reaction of chemical species in a three-dimensional (3D) geometry is a fundamental method to understand the ...

Imaging Dendritic Spines in Caenorhabditis elegans

Dendritic spines are specialized sites of synaptic innervation modulated by activity and serve as substrates for learning and memory. Recently, dendritic spines have been described for DD GABAergic neurons as the input sites from presynaptic cholinergic neurons in the motor circuit of Caenorhabditis elegans. This synaptic circuit can now serve as a powerful new in vivo model of spine morphogenesis and function that exploits the facile genetics and ready accessibility of C. elegans to live-cell imaging. 
This protocol describes experimental strategies for assessing DD spine structure and function. In this approach, a super-resolution imaging strategy is used to visualize the intricate shapes of actin-rich dendritic spines. To evaluate the DD spine function, the light-activated opsin, Chrimson, stimulates the presynaptic cholinergic neurons, and the calcium indicator, GCaMP, reports the evoked calcium transients in postsynaptic DD spines. Together, these methods comprise powerful approaches for identifying genetic determinants of dendritic spines in C. elegans that could also direct spine morphogenesis and function in the brain.

Imaging Dendritic Spines in Caenorhabditis elegans

Dendritic spines are important cellular features of the nervous system. Here live imaging methods are described for assessing the structure and function of dendritic spines in C. elegans.&#160;These approaches support the development of mutant screens for genes that define dendritic spine shape or function.

Imágenes de espinas dendríticas en Caenorhabditis elegans

Dendritic spines are specialized sites of synaptic innervation modulated by activity and serve as substrates for learning and memory. Recently, dendritic ...

Serial Block-Face Scanning Electron Microscopy (SBEM) for the Study of Dendritic Spines

Three-dimensional electron microscopy (3D EM) gives a possibility to analyze morphological parameters of dendritic spines with nanoscale resolution. In addition, some features of dendritic spines, such as volume of the spine and post-synaptic density (PSD) (representing post-synaptic part of the synapse), presence of presynaptic terminal, and smooth endoplasmic reticulum or atypical form of PSD (e.g., multi-innervated spines), can be observed only with 3D EM. By employing serial block-face scanning electron microscopy (SBEM) it is possible to obtain 3D EM data easier and in a more reproducible manner than when performing traditional serial sectioning. Here we show how to prepare mouse hippocampal samples for SBEM analysis and how this protocol can be combined with immunofluorescence study of dendritic spines. Mild fixation perfusion allows us to perform immunofluorescence studies with light microscopy on one half of the brain, while the other half was prepared for SBEM. This approach reduces the number of animals to be used for the study.

Serial Block-Face Scanning Electron Microscopy SBEM for the Study of Dendritic Spines

Serial Block-Face Scanning Electron Microscopy (SBEM) is applied to image and analyze dendritic spines in the murine hippocampus.

Microscopía electrónica de barrido serial de cara de bloque (SBEM) para el estudio de espinas dendríticas

Three-dimensional electron microscopy (3D EM) gives a possibility to analyze morphological parameters of dendritic spines with nanoscale resolution. In ...