1. Cerebro mitocondrial aislamiento (Adaptado de Brown MR et al. 9) <ol><li> Sacrificar la rata utilizando métodos aprobados por el Cuidado de Animales institucional y el empleo Comisión (IACUC). </li><li> Cortar la cabeza del animal por decapitación, cortar la piel y exponer el cráneo. </li><li> Abra el cráneo suavemente cortando con unas tijeras o pinzas gubias. Retire el cerebro. </li><li> Picar finamente el cerebro sin cerebelo en tampón de aislamiento (véase el cuadro 1) y transferirlo a un ml de vidrio / teflón homogeneizadora 5 (ver lista de equipo). </li><li> Homogeneizar el tejido con cuidado 10 veces (sin burbujas), aproximadamente 5 min. </li><li> Centrifugar la muestra a 1500 × g durante 10 min a 4 ° C en una centrífuga de sobremesa. </li><li> Guardar el sobrenadante (mitocondrial y sinaptosomas) y desechar el sedimento (materiales nucleares y desechos celulares). Centrifugar a 16.000 × g durante 10 min a 4 ° C en una centrífuga de sobremesa. </li><li> Descartarsobrenadante y volver a suspender el pellet en 500 l de tampón de aislamiento. Interrumpir sinaptosomas con un vaso ruptura celular (ver lista de equipo). Aplicar una presión de 1200 psi durante 10 min, seguido de una descompresión rápida. </li><li> Capa de la mezcla en gradientes de Ficoll (ver Tabla 2), lugar en el SW-50.1 rotor y se centrifuga a 126500 × g durante 20 min a 4 ° C en una ultracentrífuga (ver lista de equipo). El sedimento es la mitocondria purificada, la capa entre las diferentes densidades de Ficoll es sinaptosomas ininterrumpido. </li><li> Lavar la pella por centrifugación en tampón de aislamiento a 16.000 × g durante 10 min a 4 ° C en una centrífuga de sobremesa. </li></ol> 2. Submitocondriales vesículas (SMV) Aislamiento (Adaptado de Chan et al. 10) <ol><li> Vuelva a suspender las mitocondrias en 200 l de tampón de aislamiento combinada con un volumen igual de 1% de digitonina y dejar reposar en hielo durante 15 min. </li><li> Agregue más Buff Aislamientoer y se centrifuga a 16.000 xg durante 10 min a 4 ° C en una centrífuga de sobremesa. Haga esto dos veces. </li><li> Vuelva a suspender el pellet en 200 l de tampón de aislamiento y añadir 2 l de 10% Lubrol PX (C12E9). Mezcle y deje reposar en hielo durante 15 min. </li><li> Capa de mezcla en tampón de aislamiento, lugar en SW-50.1 rotor y se centrifuga a 182000 × g a 4 º C durante 1 hora. </li><li> Lavar sedimento final mediante centrifugación en una centrífuga de sobremesa en tampón de aislamiento a 16.000 × g durante 10 min a 4 ° C. </li></ol> 3. Registro electrofisiológico <ol><li> Una típica plataforma de electrofisiología incluye un amplificador, un ordenador PC equipado con una interfaz de convertidor de analógico a digital Digidata 1440A en conjunto con software de pClamp10.0, manipuladores, un microscopio, una mesa de aislamiento de vibraciones, jaula de Faraday. </li><li> Tubos capilares de vidrio de borosilicato se insertan en un Flaming / Brown Micropipetas Extractor modelo P-87. Un programa de pipeta-extractor está optimizado paragenerar pipetas con resistencias entre 80 a 100 mW. </li><li> SMVS se colocan en una solución fisiológica intracelular (ATP se añadió en el momento apropiado durante la grabación) (Tabla 3). Pipetas de patch clamp se llenan con la misma solución (sin ATP). Las grabaciones se realizan mediante la formación de un sello giga-ohmios en SMVS a temperatura ambiente. Las vesículas se visualizan por microscopía de contraste de fases con un microscopio invertido Nikon o Zeiss. </li><li> El potencial de membrana se mantiene a voltajes que van desde -100 mV a + 100 mV durante períodos de 10 segundos. Las grabaciones se filtraron a 5 kHz utilizando los circuitos del amplificador. Nivel de ruido eléctrico o parásita no específica de menos de 1 pA son deseables para la grabación de éxito. </li><li> Los datos se analizaron con el software de Clampfit 10.0, por ejemplo, para determinar la frecuencia y la amplitud de los eventos de un solo canal. La dependencia de voltaje es determinada por el trazado de una relación actual tensión. </li></ol>

<ol>
	<li>Cheng, W. C., Berman, S. B., Ivanovska, I., Jonas, E. A., Lee, S. J., Chen, Y., Kaczmarek, L. K., Pineda, F., Hardwick, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+factors+with+dual+roles+in+death+and+survival.">Mitochondrial factors with dual roles in death and survival.</a> Oncogene. 25, 4697-4705 (2006).</li><li>Duchen, M. R., 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=Mitochondria+and+calcium+in+health+and+disease.">Mitochondria and calcium in health and disease.</a> Cell Calcium. 44, 1-5 (2008).</li><li>Lemasters, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulation+of+mitochondrial+membrane+permeability+in+pathogenesis,+autophagy+and+control+of+metabolism.">Modulation of mitochondrial membrane permeability in pathogenesis, autophagy and control of metabolism.</a> J. Gastroenterol. Hepatol. 22, S31-S37 (2007).</li><li>Cox, G. B., Jans, D. A., Fimmel, A. L., Gibson, F., Hatch, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypothesis.+The+mechanism+of+ATP+synthase.+Conformational+change+by+rotation+of+the+beta-subunit.">Hypothesis. The mechanism of ATP synthase. Conformational change by rotation of the beta-subunit.</a> Biochim. Biophys. Acta. 768, 201-208 (1984).</li><li>Cox, G. B., Fimmel, A. L., Gibson, F., Hatch, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanism+of+ATP+synthase:+a+reassessment+of+the+functions+of+the+b+and+a+subunits.">The mechanism of ATP synthase: a reassessment of the functions of the b and a subunits.</a> Biochim. Biophys. Acta. 849, 62-69 (1986).</li><li>Cory, S., Huang, D. C., Adams, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Bcl-2+family:+roles+in+cell+survival+and+oncogenesis.">The Bcl-2 family: roles in cell survival and oncogenesis.</a> Oncogene. 22, 8590-8607 (2003).</li><li>Vander Heiden, M. G., Thompson, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bcl-2+proteins:+regulators+of+apoptosis+or+of+mitochondrial+homeostasis.">Bcl-2 proteins: regulators of apoptosis or of mitochondrial homeostasis.</a> Nat. Cell Biol. 1, 209-216 (1999).</li><li>Alavian, K. N., Li, H., Collis, L., Bonanni, L., Zeng, L., Sacchetti, S., Lazrove, E., Nabili, P., Flaherty, B., Graham, M., Chen, Y., Messerli, S. M., Mariggio, M. A., Rahner, C., McNay, E., Shore, G. C., Smith, P. J. S., Hardwick, J. M., Jonas, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bcl-xL+regulates+metabolic+efficiency+of+neurons+through+interaction+with+the+mitochondrial+F1FO+ATP+synthase.">Bcl-xL regulates metabolic efficiency of neurons through interaction with the mitochondrial F1FO ATP synthase.</a> Nat. Cell Biol. 13 (10), 1224-1233 (2011).</li><li>Brown, M. R., Sullivan, P. G., Dorenbos, K. A., Modafferi, E. A., Geddes, J. W., Steward, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitrogen+disruption+of+synaptoneurosomes:+an+alternative+method+to+isolate+brain+mitochondria.">Nitrogen disruption of synaptoneurosomes: an alternative method to isolate brain mitochondria.</a> Journal of Neuroscience Methods. 137, 299-303 (2004).</li><li>Chan, T. L., Greenawalt, J. W., Pedersen, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+ultrastructural+properties+of+a+mitochondrial+inner+membrane+fraction+deficient+in+outer+membrane+and+matrix+activities.">Biochemical and ultrastructural properties of a mitochondrial inner membrane fraction deficient in outer membrane and matrix activities.</a> J. Cell Biol. 45 (2), 291-305 (1970).</li><li>Young, H. K. o., Delannoy, M., Hullihen, J., Chiu, W., Pedersen, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+ATP+Synthasomes.">Mitochondrial ATP Synthasomes.</a> J. Biol. Chem. 278 (14), 12305-12309 (2003).</li></ol>

No hay conflictos de interés declarado.

Los métodos descritos en este documento permiten el aislamiento de las mitocondrias pura al final de la etapa 1 y las vesículas submitocondriales (SMVS) después de la etapa 2 a partir de todo el cerebro y sin distinción de células phenotypes.SMVspurified por este método están esencialmente libres de contaminación por otros orgánulos subcelulares como se muestra en Figura 1 y nuestro trabajo anterior (Alavian KN et al. 8) y conservar su integridad estructural y funcional ante...

<table border="1">
 <tbody>
 <tr>
 <td>Name </td>
 <td>Company</td>
 <td>Catalogue number</td>
 </tr>
 <tr>
 <td>Potter-Elvehjem Tissue Grinder withPTFEPestle</td>
 <td>Krackeler Scientific, Inc.</td>
 <td>1-7725T-5 </td>
 </tr>
 <tr>
 <td>Eppendorf Centrifuge 5424 </td>
 <td>Eppendorf </td>
 <td>5424 000.410</td>
 </tr>
 <tr>
 <td>4639 Cell Disruption Vessel</td>
 <td>Parr Instrument Company</td>
 <td>4639</td>
 </tr>
 <tr>
 <td>Ficoll</td>
 <td>Sigma-Aldrich</td>
 <td>F5415</td>
 </tr>
 <tr>
 <td>Polycarbonate centrifuge tubes</td>
 <td>Beckman Coulter</td>
 <td>P20314</td>
 </tr>
 <tr>
 <td>SW-50.1 rotor </td>
 <td>Beckman Coulter</td>
 <td></td>
 </tr>
 <tr>
 <td>L8-70M Ultracentrifuge</td>
 <td>Beckman Coulter</td>
 <td></td>
 </tr>
 <tr>
 <td>Digitonin</td>
 <td>Sigma-Aldrich</td>
 <td>D5628 </td>
 </tr>
 <tr>
 <td>Lubrol PX (C12E9) </td>
 <td>Calbiochem</td>
 <td>205534</td>
 </tr>
 <tr>
 <td>Axopatch 200B </td>
 <td>Axon Instruments </td>
 <td></td>
 </tr>
 <tr>
 <td>Digidata 1440A </td>
 <td>Molecular Device</td>
 <td></td>
 </tr>
 <tr>
 <td>pClamp10.0</td>
 <td>Molecular Device</td>
 <td></td>
 </tr>
 <tr>
 <td>Manipulator</td>
 <td>Sutter Instrument</td>
 <td></td>
 </tr>
 <tr>
 <td>Borosilicate glass capillary</td>
 <td>World Precision Instruments</td>
 <td>1308325</td>
 </tr>
 <tr>
 <td>Flaming/Brown Micropipette Puller Model P-87</td>
 <td>Sutter Instrument</td>
 <td></td>
 </tr>
 </tbody>
</table>

f1fo atpase vesicle preparation and technique for performing patch clamp recordings of submitochondrial vesicle membranes

Las mitocondrias están implicadas en muchas funciones celulares importantes, incluyendo el metabolismo, la supervivencia a 1, el desarrollo y la señalización de calcio 2. Dos de las funciones mitocondriales más importantes están relacionados con la producción eficiente de ATP, la energía de la célula, por la fosforilación oxidativa, y la mediación de señales para la muerte celular programada 3. La enzima principal responsable de la producción de ATP es la sintasa F1FO-ATP, también llamada ATP sintasa 4-5. En los últimos años, el papel de las mitocondrias en la muerte celular apoptótica y necrótica ha recibido una atención considerable. En la muerte celular apoptótica, Bcl-2 proteínas de la familia tales como Bax entran en la membrana mitocondrial externa, oligomerize y permeabilizan la membrana externa, la liberación de factores pro-apoptóticos en el citosol 6. En la muerte celular necrótica clásico, tal como la producida por la isquemia o la excitotoxicidad en neuronas, un largE, aumento mal regulado en calcio matriz contribuye a la apertura de un poro de la membrana interna, el poro de transición de permeabilidad mitocondrial o mPTP. Esto despolariza la membrana interna y causa cambios osmóticos, lo que contribuye a la ruptura de la membrana externa, la liberación de factores pro-apoptóticos, y la disfunción metabólica. Muchas proteínas incluyendo Bcl-xL 7 interactúan con F1FO ATP sintasa, modulando su función. Bcl-xL interactúa directamente con la subunidad beta de la ATP sintasa F1FO, y esta interacción disminuye la conductancia de una fuga dentro de la F1FOATPasecomplex, el aumento de la red de transporte de H + por F1FO durante F1FO actividad ATPasa 8 y aumentando así la eficiencia mitocondrial. Para estudiar la actividad y la modulación de la ATP sintasa, se aislaron a partir de cerebro de roedores vesículas submitocondriales (SMVS) que contienen F1FO ATPasa. Los SMVS conservan la integridad estructural y funcional de la F1FO ATPasa como se muestra en Alavian et al. Aquí se describe un métodoque hemos usado con éxito para el aislamiento de SMVS de cerebro de rata y delinear la técnica de patch clamp para analizar la actividad del canal (la conductancia de iones de fuga) de los SMVS.

El primer paso de nuestro protocolo permite el aislamiento de mitocondrias purificadas como se muestra por Western blot en la Figura 1. En la Figura 2 se muestra un ejemplo de una grabación parche vesícula submitocondriales derivado del cerebro. Uso de la configuración de parche de dentro a fuera se demuestra la actividad del canal modulado por la ATP. El control (CTL) de grabación (izquierda) muestra la actividad del canal de múltiples conductancia con un pico de conductancia de 6...

Watch this Scientific Journal Video about F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes at JoVE.com

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

Un método para aislar vesículas submitochondrial enriquecidas en F1FO complejos ATP sintasa de cerebro de rata se describe. Estas vesículas permiten el estudio de la actividad de ATPasa F1FO complejo y su modulación mediante la técnica de la grabación de patch clamp.

<sub&gt; 1</sub&gt; F<sub&gt; O</sub&gt; ATPasa preparación de vesículas y técnica para realizar Patch clamp grabaciones de membranas de la vesícula submitocondriales

Mitochondria are involved in many important cellular  functions including metabolism, survival1, development and, calcium signaling2. Two of the most ...

f1fo-atpase-vesicle-preparation-technique-for-performing-patch-clamp

Research

JoVE Journal

Neuroscience

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

10.2K vistas.  Yale University. Un método para aislar vesículas submitochondrial enriquecidas en F1FO complejos ATP sintasa de cerebro de rata se describe. Estas vesículas permiten el estudio de la actividad de ATPasa F1FO complejo y su modulación mediante la técnica de la grabación de patch clamp.

Video: F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

Patch Clamp Recordings from Mouse Retinal Neurons in a Dark-adapted Slice Preparation

Our visual experience is initiated when the visual pigment in our retinal photoreceptors absorbs photons of light energy and initiates a cascade of intracellular events that lead to closure of cyclic-nucleotide-gated channels in the cell membrane. The resulting change in membrane potential leads in turn to reductions in the amount of neurotransmitter release from both rod and cone synaptic terminals. To measure how the light-evoked change in photoreceptor membrane potential leads to downstream activity in the retina, scientists have made electrophysiological recordings from retinal slice preparations for decades1,2. In the past these slices have been cut manually with a razor blade on retinal tissue that is attached to filter paper; in recent years another method of slicing has been developed whereby retinal tissue is embedded in low gelling temperature agar and sliced in cool solution with a vibrating microtome3,4. This preparation produces retinal slices with less surface damage and very robust light-evoked responses. Here we document how this procedure can be done under infrared light to avoid bleaching the visual pigment.

Here we describe a procedure for generating dark-adapted slices of the mouse retina for electrophysiological recordings.

Grabaciones de patch clamp de neuronas de ratón de retina en una rebanada preparación adaptada a la oscuridad

Our visual experience is initiated when the visual pigment in our retinal photoreceptors absorbs photons of light energy and initiates a cascade of ...

Investigación

Neurociencias

Paired Patch Clamp Recordings from Motor-neuron and Target Skeletal Muscle in Zebrafish

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target muscle. This is a direct consequence of the accessibility to both cell types and ability to visually distinguish the single segmental CaP motor-neuron on the basis of morphology and location. This video demonstrates the microscopic methods used to identify a CaP motor-neuron and target muscle cells as well as the methodologies for recording from each cell type. Identification of the CaP motor-neuron type is confirmed by either dye filling or by the biophysical features such as action potential waveform and cell input resistance. Motor-neuron recordings routinely last for one hour permitting long-term recordings from multiple different target muscle cells. Control over the motor-neuron firing pattern enables measurements of the frequency-dependence of synaptic transmission at the neuromuscular junction. Owing to a large quantal size and the low noise provided by whole cell voltage clamp, all of the unitary events can be resolved in muscle. This feature permits study of basic synaptic properties such as release properties, vesicle recycling, as well as synaptic depression and facilitation. The advantages offered by this in vivo preparation eclipse previous neuromuscular model systems studied wherein the motor-neurons are usually stimulated by extracellular electrodes and the muscles are too large for whole cell patch clamp. The zebrafish preparation is amenable to combining electrophysiological analysis with a wide range of approaches including transgenic lines, morpholino knockdown, pharmacological intervention and in vivo imaging. These approaches, coupled with the growing number of neuromuscular disease models provided by mutant lines of zebrafish, open the door for new understanding of human neuromuscular disorders.

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target skeletal muscle. This video demonstrates the microscopic methods used to identify a segmental CaP motor-neuron and target muscle cells as well as the methodologies for recording from each cell type.

Emparejados grabaciones patch clamp de neurona motora y el músculo esquelético de destino en el pez cebra

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target muscle.  ...

Culturing and Electrophysiology of Cells on NRCC Patch-clamp Chips

Due to its exquisite sensitivity and the ability to monitor and control individual cells at the level of ion channels, patch-clamping is the gold standard of electrophysiology applied to disease models and pharmaceutical screens alike 1. The method traditionally involves gently contacting a cell with a glass pipette filled by a physiological solution in order to isolate a patch of the membrane under its apex 2. An electrode inserted in the pipette captures ion-channel activity within the membrane patch or, when ruptured, for the whole cell. In the last decade, patch-clamp chips have been proposed as an alternative 3, 4: a suspended film separates the physiological medium from the culture medium, and an aperture microfabricated in the film replaces the apex of the pipette. Patch-clamp chips have been integrated in automated systems and commercialized for high-throughput screening 5. To increase throughput, they include the fluidic delivery of cells from suspension, their positioning on the aperture by suction, and automated routines to detect cell-to-probe seals and enter into whole cell mode. We have reported on the fabrication of a silicon patch-clamp chip with optimized impedance and orifice shape that permits the high-quality recording of action potentials in cultured snail neurons 6; recently, we have also reported progress towards interrogating mammalian neurons 7. Our patch-clamp chips are fabricated at the Canadian Photonics Fabrication Centre 8, a commercial foundry, and are available in large series. We are eager to engage in collaborations with electrophysiologists to validate the use of the NRCC technology in different models. The chips are used according to the general scheme represented in Figure 1: the silicon chip is at the bottom of a Plexiglas culture vial and the back of the aperture is connected to a subterranean channel fitted with tubes at either end of the package. Cells are cultured in the vial and the cell on top of the probe is monitored by a measuring electrode inserted in the channel.The two outside fluidic ports facilitate solution exchange with minimal disturbance to the cell; this is an advantage compared to glass pipettes for intracellular perfusion.
<img alt="Figure 1" src="/files/ftp_upload/3288/3288fig1.jpg" />
Figure 1. Principle of measurement using the NRCC patch-clamp chip
We detail here the protocols to sterilize and prime the chips, load them with medium, plate them with cells, and finally use them for electrophysiological recordings.

We show how planar patch-clamp chips fabricated at the National Research Council of Canada are sterilized, primed, loaded with medium, plated with cells, and used for electrophysiological recordings.

El cultivo y la electrofisiología de las células en NRCC de patch-clamp chips

Due to its exquisite sensitivity and the ability to monitor and control individual cells at the level of ion channels, patch-clamping is the gold standard ...

Patch Clamp Recordings in Inner Ear Hair Cells Isolated from Zebrafish

Patch clamp analyses of the voltage-gated channels in sensory hair cells isolated from a variety of species have been described previously1-4 but this video represents the first application of those techniques to hair cells from zebrafish. Here we demonstrate a method to isolate healthy, intact hair cells from all of the inner ear end-organs: saccule, lagena, utricle and semicircular canals. Further, we demonstrate the diversity in hair cell size and morphology and give an example of the kinds of patch clamp recordings that can be obtained. The advantage of the use of this zebrafish model system over others stems from the availability of zebrafish mutants that affect both hearing and balance. In combination with the use of transgenic lines and other techniques that utilize genetic analysis and manipulation, the cell isolation and electrophysiological methods introduced here should facilitate greater insight into the roles hair cells play in mediating these sensory modalities.

The purpose of this video is to demonstrate procedures for obtaining healthy, intact hair cells from the inner ear organs of adult zebrafish and then using them for patch clamp studies aimed at characterizing the biophysical properties of their voltage-gated channels.

Grabaciones de patch clamp en Inner células del oído pelo Aislado de pez cebra

Patch  clamp analyses of the voltage-gated channels in sensory hair cells isolated  from a variety of species have been described previously1-4 but this  ...

Isolation of Sensory Neurons of Aplysia californica for Patch Clamp Recordings of Glutamatergic Currents

The marine gastropod mollusk Aplysia californica has a venerable history as a model of nervous system function, with particular significance in studies of learning and memory. The typical preparations for such studies are ones in which the sensory and motoneurons are left intact in a minimally dissected animal, or a technically elaborate neuronal co-culture of individual sensory and motoneurons. Less common is the isolated neuronal preparation in which small clusters of nominally homogeneous neurons are dissociated into single cells in short term culture. Such isolated cells are useful for the biophysical characterization of ion currents using patch clamp techniques, and targeted modulation of these conductances. A protocol for preparing such cultures is described. The protocol takes advantage of the easily identifiable glutamatergic sensory neurons of the pleural and buccal ganglia, and describes their dissociation and minimal maintenance in culture for several days without serum.

Isolation of Sensory Neurons of Aplysia californica for Patch Clamp Recordings of Glutamatergic Currents

We describe the dissection of the nervous system of the marine sea hare Aplysia after anesthesia, the isolation of neurons for short term-tissue culture, and recordings of single cell ion currents via the patch clamp technique.

El aislamiento de las neuronas sensoriales de<em&gt; Aplysia californica</em&gt; Se Patch clamp grabaciones de Corrientes glutamatérgicos

The marine gastropod mollusk Aplysia californica has a venerable  history as a model of nervous system function, with particular significance in  studies ...

Patch Clamp Recordings from Embryonic Zebrafish Mauthner Cells

Mauthner cells (M-cells) are large reticulospinal neurons located in the hindbrain of teleost fish. They are key neurons involved in a characteristic behavior known as the C-start or escape response that occurs when the organism perceives a threat. The M-cell has been extensively studied in adult goldfish where it has been shown to receive a wide range of excitatory, inhibitory and neuromodulatory signals1. We have been examining M-cell activity in embryonic zebrafish in order to study aspects of synaptic development in a vertebrate preparation. In the late 1990s Ali and colleagues developed a preparation for patch clamp recording from M-cells in zebrafish embryos, in which the CNS was largely intact2,3,4. The objective at that time was to record synaptic activity from hindbrain neurons, spinal cord neurons and trunk skeletal muscle while maintaining functional synaptic connections within an intact brain-spinal cord preparation. This preparation is still used in our laboratory today. To examine the mechanisms underlying developmental synaptic plasticity, we record excitatory (AMPA and NMDA-mediated)5,6 and inhibitory (GABA and glycine) synaptic currents from developing M-cells. Importantly, this unique preparation allows us to return to the same cell (M-cell) from preparation to preparation to carefully examine synaptic plasticity and neuro-development in an embryonic organism. The benefits provided by this preparation include 1) intact, functional synaptic connections onto the M-cell, 2) relatively inexpensive preparations, 3) a large supply of readily available embryos 4) the ability to return to the same cell type (i.e. M-cell) in every preparation, so that synaptic development at the level of an individual cell can be examined from fish to fish, and 5) imaging of whole preparations due to the transparent nature of the embryos.

We have developed an intact brain-spinal cord preparation to record and monitor electrical activity via patch clamp recording from the Mauthner neurons and other reticulospinal cells in zebrafish embryos. Thus, we are able to record excitatory and inhibitory synaptic currents, voltage-gated channel activity and action potentials from key neurons in a developing embryo.

Patch Clamp Las grabaciones de las células embrionarias de pez cebra Mauthner

Mauthner cells (M-cells) are large  reticulospinal neurons located in the hindbrain of teleost fish. They are key  neurons involved in a characteristic ...

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.

Plenario de células patch-clamp grabaciones de Morphologically- e identificados-neuroquímicamente interneuronas del hipocampo

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

Electrophysiological and Morphological Characterization of Neuronal Microcircuits in Acute Brain Slices Using Paired Patch-Clamp Recordings

The combination of patch clamp recordings from two (or more) synaptically coupled neurons (paired recordings) in acute brain slice preparations with simultaneous intracellular biocytin filling allows a correlated analysis of their structural and functional properties. With this method it is possible to identify and characterize both pre- and postsynaptic neurons by their morphology and electrophysiological response pattern. Paired recordings allow studying the connectivity patterns between these neurons as well as the properties of both chemical and electrical synaptic transmission. Here, we give a step-by-step description of the procedures required to obtain reliable paired recordings together with an optimal recovery of the neuron morphology. We will describe how pairs of neurons connected via chemical synapses or gap junctions are identified in brain slice preparations. We will outline how neurons are reconstructed to obtain their 3D morphology of the dendritic and axonal domain and how synaptic contacts are identified and localized. We will also discuss the caveats and limitations of the paired recording technique, in particular those associated with dendritic and axonal truncations during the preparation of brain slices because these strongly affect connectivity estimates. However, because of the versatility of the paired recording approach it will remain a valuable tool in characterizing different aspects of synaptic transmission at identified neuronal microcircuits in the brain.

Patch-clamp recordings and simultaneous intracellular biocytin filling of synaptically coupled neurons in acute brain slices allow a correlated analysis of their structural and functional properties. The aim of this protocol is to describe the essential technical steps of electrophysiological recording from neuronal microcircuits and their subsequent morphological analysis.

Electrofisiológico y Caracterización Morfológica de microcircuitos neuronales en el infarto agudo rodajas de cerebro Usando Emparejados patch-clamp grabaciones

The combination of patch clamp recordings from two (or more) synaptically coupled neurons (paired recordings) in acute brain slice preparations with ...

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.

Las grabaciones de células enteras Patch-clamp en rodajas de cerebro

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

Subcellular Patch-clamp Recordings from the Somatodendritic Domain of Nigral Dopamine Neurons

Dendrites of dopaminergic neurons receive and convey synaptic input, support action potential back-propagation and neurotransmitter release. Understanding these fundamental functions will shed light on the information transfer in these neurons. Dendritic patch-clamp recordings provide the possibility to directly examine the electrical properties of dendrites and underlying voltage-gated ion channels. However, these fine structures are not easily accessible to patch pipettes because of their small diameter. This report describes a step-by-step procedure to collect stable and reliable recordings from the dendrites of dopaminergic neurons in acute slices. Electrophysiological measurements are combined with post hoc recovery of cell morphology. Successful experiments rely on improved preparation of slices, solutions and pipettes, adequate adjustment of the optics and stability of the pipette in contact with the recorded structure. Standard principles of somatic patch-clamp recording are applied to dendrites but with a gentler approach of the pipette. These versatile techniques can be implemented to address various questions concerning the excitable properties of dendrites.

Subcellular patch-clamp recordings offer the possibility to investigate the functional properties of dendrites. However these fine structures are not easily accessible due to their small diameter. The protocol described here aims to facilitate the collection of stable and reliable recordings from the dendrites of dopamine neurons in slices in vitro.

Subcelulares patch-clamp grabaciones desde el dominio somatodendrítica de la sustancia nigra dopamina Neuronas

Dendrites of dopaminergic neurons receive and convey synaptic input, support action potential back-propagation and neurotransmitter release. Understanding ...