Somos las gracias por su apoyo: Beca de la Commonwealth del Reino Unido la financiación de la Comisión (HP), EPSRC (HP), BBSRC (NMF) y la Unión Europea, las acciones Marie Curie (NMF).

<ol>
	<li>O'Donnell, C., Nolan, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tuning+of+synaptic+responses:+an+organizing+principle+for+optimization+of+neural+circuits.">Tuning of synaptic responses: an organizing principle for optimization of neural circuits.</a> Trends Neurosci. 34, 51-60 (2011).</li><li>Garden, D. L. F., Dodson, P. D., O'Donnell, C., White, M. D., Nolan, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tuning+of+synaptic+integration+in+the+medial+entorhinal+cortex+to+the+organization+of+grid+cell+firing+fields.">Tuning of synaptic integration in the medial entorhinal cortex to the organization of grid cell firing fields.</a> Neuron. 60, 875-889 (2008).</li><li>Kuba, H., Yamada, R., Fukui, I., Ohmori, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tonotopic+specialization+of+auditory+coincidence+detection+in+nucleus+laminaris+of+the+chick.">Tonotopic specialization of auditory coincidence detection in nucleus laminaris of the chick.</a> Journal of Neuroscience. 25, 1924-1934 (2005).</li><li>Hafting, T., Fyhn, M., Molden, S., Moser, M. -. B., Moser, E. 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A., Frans&#233;n, E., Hasselmo, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Temporal+frequency+of+subthreshold+oscillations+scales+with+entorhinal+grid+cell+field+spacing.">Temporal frequency of subthreshold oscillations scales with entorhinal grid cell field spacing.</a> Science. 315, 1719-1722 (2007).</li><li>Giocomo, L. M., Hasselmo, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time+constants+of+h+current+in+layer+II+stellate+cells+differ+along+the+dorsal+to+ventral+axis+of+medial+entorhinal+cortex.">Time constants of h current in layer II stellate cells differ along the dorsal to ventral axis of medial entorhinal cortex.</a> Journal of Neuroscience. 28, 9414-9425 (2008).</li><li>Burgalossi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microcircuits+of+functionally+identified+neurons+in+the+rat+medial+entorhinal+cortex.">Microcircuits of functionally identified neurons in the rat medial entorhinal cortex.</a> Neuron. 70, 773-786 (2011).</li><li>Dodson, P. D., Pastoll, H., Nolan, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dorsal-ventral+organization+of+theta-like+activity+intrinsic+to+entorhinal+stellate+neurons+is+mediated+by+differences+in+stochastic+current+fluctuations.">Dorsal-ventral organization of theta-like activity intrinsic to entorhinal stellate neurons is mediated by differences in stochastic current fluctuations.</a> J. Physiol. (Lond). 589, 2993-3008 (2011).</li><li>Nolan, M., Dudman, J., Dodson, P., Santoro, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HCN1+channels+control+resting+and+active+integrative+properties+of+stellate+cells+from+layer+II+of+the+entorhinal+cortex.">HCN1 channels control resting and active integrative properties of stellate cells from layer II of the entorhinal cortex.</a> Journal of Neuroscience. 27, (2007).</li><li>Boehlen, A., Heinemann, U., Erchova, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+range+of+intrinsic+frequencies+represented+by+medial+entorhinal+cortex+stellate+cells+extends+with+age.">The range of intrinsic frequencies represented by medial entorhinal cortex stellate cells extends with age.</a> Journal of Neuroscience. 30, 4585-4589 (2010).</li><li>Klink, R., Alonso, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+characteristics+of+layer+II+projection+neurons+in+the+rat+medial+entorhinal+cortex.">Morphological characteristics of layer II projection neurons in the rat medial entorhinal cortex.</a> Hippocampus. 7, 571-583 (1997).</li><li>van Groen, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entorhinal+cortex+of+the+mouse:+cytoarchitectonical+organization.">Entorhinal cortex of the mouse: cytoarchitectonical organization.</a> Hippocampus. 11, 397-407 (2001).</li><li>Dolorfo, C. L., Amaral, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entorhinal+cortex+of+the+rat:+organization+of+intrinsic+connections.">Entorhinal cortex of the rat: organization of intrinsic connections.</a> The Journal of Comparative Neurology. 398, 49-82 (1998).</li></ol>

No hay nada que revelar.

Para facilitar la investigación de las propiedades del circuito MEC que siguen a una organización dorsal-ventral que hemos descrito aquí con detalle un procedimiento para producir una preparación de corte parasagital que preserva la medida dorsal-ventral del MEC. Los pasos críticos Extracción del cerebro del animal. Tenga especial cuidado para evitar ejercer presión sobre el cerebro. Esto es más importante que la rápida eliminación del cer...

<table border="1"><tbody><tr><td></td><td> Corte ACSF (mM) </td><td> Norma ACSF (mM) </td><td> Solución interna (mM) </td><td> CASNumber </td><td> Proveedor Número de catálogo </td></tr><tr><td> NaCl </td><td> 86 </td><td> 124 </td><td></td><td> 7647-14-5 </td><td> Sigma S9888 </td></tr><tr><td> NaH 2 PO 4 </td><td> 1.2 </td><td> 1.2 </td><td></td><td> 13472-35-0 </td><td> Sigma 71505 </td></tr><tr><td> KCl </td><td> 2.5 </td><td> 2.5 </td><td> 10 </td><td> 7447-40-7 </td><td> Sigma P3911 </td></tr><tr><td> NaHCO $ 3 </td><td> 25 </td><td> 25 </td><td></td><td> 144-55-8 </td><td> Fischer S/4240 </td></tr><tr><td> Glucosa </td><td> 25 </td><td> 20 </td><td></td><td> 50-99-7 </td><td> Sigma G5767 </td></tr><tr><td> Sacarosa </td><td> 75 </td><td></td><td></td><td> 57-50-1 </td><td> Sigma S5016 </td></tr><tr><td> CaliforniaCl 2 </td><td> 0.5 </td><td> 2 </td><td></td><td> 10043-52-4 </td><td> VWR 190464K </td></tr><tr><td> MgCl 2 </td><td> 7 </td><td> 1 </td><td> 2 </td><td> 7786-30-3 </td><td> Sigma 63020 </td></tr><tr><td> K Gluconato </td><td></td><td></td><td> 130 </td><td> 299-27-4 </td><td> Sigma G4500 </td></tr><tr><td> HEPES </td><td></td><td></td><td> 10 </td><td> 7365-45-9 </td><td> Sigma H3375 </td></tr><tr><td> EGTA </td><td></td><td></td><td> 0.1 </td><td> 67-42-5 </td><td> Sigma E4378 </td></tr><tr><td> Na 2 ATP </td><td></td><td></td><td> 2 </td><td> 34369-07-8 </td><td> Sigma A7699 </td></tr><tr><td> Na 2 GTP </td><td></td><td></td><td> 0.3 </td><td> 36051-31-7 </td><td> Sigma G8877 </td></tr><tr><td> NaPhospho-creatina </td><td></td><td></td><td> 10 </td><td> 19333-65-4 </td><td> Sigma P7936 </td></tr><tr><td> Biocitina (opcional) </td><td></td><td></td><td> 2.7 </td><td> 576-19-2 </td><td&gt; Sigma B4261 </td></tr></tbody></table> Tabla 1. Corte ACSF, ACSF estándar y K-gluconato recetas solución interna.

preparation of parasagittal slices for the investigation of dorsal-ventral organization of the rodent medial entorhinal cortex

Ciencia de la Computación en el cerebro se basa en las neuronas que responden adecuadamente a las entradas sinápticas. Las neuronas se diferencian en su complemento y la distribución de los canales iónicos de membrana que determinan la forma en que responden a las entradas sinápticas. Sin embargo, la relación entre estas propiedades y función celular neuronal en animales de comportarse no se entiende bien. Una aproximación a este problema consiste en investigar topográficamente organizadas circuitos neuronales en el que la posición de los mapas de neuronas individuales en la información que codificar o cálculos que llevan a cabo 1. Los experimentos con este enfoque sugiere principios para el ajuste de las respuestas sinápticas que subyacen a la codificación de información en los circuitos sensoriales y cognitivas 2,3. La organización topográfica de las representaciones espaciales a lo largo del eje dorsal-ventral medial de la corteza entorrinal (MEC) ofrece una oportunidad para establecer relaciones entre los mecanismos celulares y cálculos importante para la cognición espacial. Las neuronas de la capa II del MEC roedores codificar la localización del uso de la red-como disparar los campos 6.4. Para las neuronas que se encuentran en posiciones dorsal en el MEC la distancia entre los campos de tiro individuales que forman una rejilla es del orden de 30 cm, mientras que para las neuronas en las posiciones progresivamente más ventral esta distancia aumenta hasta más de 1 m. Varios estudios han revelado las propiedades celulares de las neuronas en la capa II del MEC que, como la separación entre los campos de la rejilla de cocción, también se diferencian de acuerdo a su posición dorsal-ventral, lo que sugiere que estas propiedades celulares son importantes para el cálculo espacial 2,7-10. Aquí se describen los procedimientos para la preparación y registro electrofisiológico de rodajas de cerebro que mantienen la medida de dorsal-ventral de la investigación MEC habilitación de la organización topográfica de las propiedades biofísicas y anatómico de las neuronas del MEC. La posición dorso-ventral del n identificadoseurons en relación con puntos de referencia anatómicos es difícil establecer con precisión con los protocolos que utilizan las rebanadas horizontales de MEC 7,8,11,12, ya que es difícil establecer puntos de referencia para la exacta ubicación de dorsal-ventral de la rebanada. Los procedimientos aquí descritos permiten la medición precisa y consistente de la ubicación de las celdas grabadas a lo largo del eje dorsal-ventral del MEC, así como la visualización de los gradientes moleculares 2,10. Los procedimientos se han desarrollado para su uso con ratones adultos (&gt; 28 días) y se han empleado con éxito con ratones hasta 1,5 años de edad. Con ajustes que podría ser utilizado con más jóvenes ratones u otras especies de roedores. Un sistema estandarizado de preparación y de medición ayudará a la investigación sistemática de las propiedades celulares y microcircuitos de esta zona.

Watch this Scientific Journal Video about Preparation of Parasagittal Slices for the Investigation of Dorsal-ventral Organization of the Rodent Medial Entorhinal Cortex at JoVE.com

Preparation of Parasagittal Slices for the Investigation of Dorsal-ventral Organization of the Rodent Medial Entorhinal Cortex

Se describen los procedimientos para la preparación y registro electrofisiológico de rodajas de cerebro que mantienen el eje dorsal-ventral medial de la corteza entorrinal (MEC). Debido a que la codificación neural de la localización sigue una organización dorsal-ventral en el MEC, estos procedimientos de facilitar la investigación de los mecanismos celulares importantes para la navegación y la memoria.

Preparación de las rebanadas parasagitales para la Investigación de dorsal-ventral Organización de los roedores de corteza entorrinal medial

Computation in the brain relies on neurons responding appropriately to their synaptic inputs. Neurons differ in their complement and distribution of ...

preparation-parasagittal-slices-for-investigation-dorsal-ventral

Research

JoVE Journal

Neuroscience

15.5K vistas.  University of Edinburgh. Se describen los procedimientos para la preparación y registro electrofisiológico de rodajas de cerebro que mantienen el eje dorsal-ventral medial de la corteza entorrinal (MEC). Debido a que la codificación neural de la localización sigue una organización dorsal-ventral en el MEC, estos procedimientos de facilitar la investigación de los mecanismos celulares importantes para la navegación y la memoria.

Video: Preparation of Parasagittal Slices for the Investigation of Dorsal-ventral Organization of the Rodent Medial Entorhinal Cortex

Brain Imaging Investigation of the Neural Correlates of Emotion Regulation

The ability to control/regulate emotions is an important coping mechanism in the face of emotionally stressful situations. Although significant progress has been made in understanding conscious/deliberate emotion regulation (ER), less is known about non-conscious/automatic ER and the associated neural correlates. This is in part due to the problems inherent in the unitary concepts of automatic and conscious processing1. Here, we present a protocol that allows investigation of the neural correlates of both deliberate and automatic ER using functional magnetic resonance imaging (fMRI). This protocol allows new avenues of inquiry into various aspects of ER. For instance, the experimental design allows manipulation of the goal to regulate emotion (conscious vs. non-conscious), as well as the intensity of the emotional challenge (high vs. low). Moreover, it allows investigation of both immediate (emotion perception) and long-term effects (emotional memory) of ER strategies on emotion processing. Therefore, this protocol may contribute to better understanding of the neural mechanisms of emotion regulation in healthy behaviour, and to gaining insight into possible causes of deficits in depression and anxiety disorders in which emotion dysregulation is often among the core debilitating features.

We present a protocol that allows investigation of the neural correlates of deliberate and automatic emotion regulation, using functional magnetic resonance imaging. This protocol can be used in healthy participants, both young and older, as well as in clinical patients.

La investigación del cerebro imágenes de los correlatos neurales de regulación de las emociones

The ability to control/regulate emotions is an important coping mechanism in the face of emotionally stressful situations. Although significant progress ...

Investigación

Neurociencias

Brain Imaging Investigation of the Memory-Enhancing Effect of Emotion

Emotional events tend to be better remembered than non-emotional events1,2. One goal of cognitive and affective neuroscientists is 
to understand the neural mechanisms underlying this enhancing effect of emotion on memory. A method that has proven particularly influential in the 
investigation of the memory-enhancing effect of emotion is the so-called subsequent memory paradigm (SMP). This method was originally used to investigate the 
neural correlates of non-emotional memories3, and more recently we and others also applied it successfully to studies of emotional memory (reviewed in4, 5-7). 
Here, we describe a protocol that allows investigation of the neural correlates of the memory-enhancing effect of emotion using the SMP in conjunction with 
event-related functional magnetic resonance imaging (fMRI). An important feature of the SMP is that it allows separation of brain activity specifically 
associated with memory from more general activity associated with perception. Moreover, in the context of investigating the impact of emotional stimuli, 
SMP allows identification of brain regions whose activity is susceptible to emotional modulation of both general/perceptual and memory-specific processing. 
This protocol can be used in healthy subjects8-15, as well as in clinical patients where there are alterations in the neural correlates of emotion perception 
and biases in remembering emotional events, such as those suffering from depression and post-traumatic stress disorder (PTSD)16, 17.

We present a protocol that uses functional magnetic resonance imaging to investigate the neural correlates of the memory-enhancing effect of emotion. This protocol allows identification of brain activity specifically linked to memory-related processing, contrary to more general perceptual processing, and can be used with healthy and clinical populations.

La investigación del cerebro de imagen del efecto de la memoria-Mejora de la emoción

Emotional events tend to be better remembered than non-emotional events1,2. One goal of cognitive and affective neuroscientists is 
to understand the ...

Brain Imaging Investigation of the Impairing Effect of Emotion on Cognition

Emotions can impact cognition by exerting both enhancing (e.g., better memory for emotional events) and impairing (e.g., increased emotional distractibility) effects (reviewed in 1). Complementing our recent protocol 2 describing a method that allows investigation of the neural correlates of the memory-enhancing effect of emotion (see also 1, 3-5), here we present a protocol that allows investigation of the neural correlates of the detrimental impact of emotion on cognition. The main feature of this method is that it allows identification of reciprocal modulations between activity in a ventral neural system, involved in 'hot' emotion processing (HotEmo system), and a dorsal system, involved in higher-level 'cold' cognitive/executive processing (ColdEx system), which are linked to cognitive performance and to individual variations in behavior (reviewed in 1). Since its initial introduction 6, this design has proven particularly versatile and influential in the elucidation of various aspects concerning the neural correlates of the detrimental impact of emotional distraction on cognition, with a focus on working memory (WM), and of coping with such distraction 7,11, in both healthy 8-11 and clinical participants 12-14.

We present a protocol that allows investigation of the neural mechanisms mediating the detrimental impact of emotion on cognition, using functional magnetic resonance imaging. This protocol can be used with both healthy and clinical participants.

La investigación del cerebro de imagen del efecto perjudicial de la emoción sobre la cognición

Emotions can impact cognition by exerting both enhancing (e.g., better memory for emotional events) and impairing (e.g., increased emotional ...

Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex

Although the brain represents less than 5% of the body by mass, it utilizes approximately one quarter of the glucose used by the body at rest1. The function of non rapid eye movement sleep (NREMS), the largest portion of sleep by time, is uncertain. However, one salient feature of NREMS is a significant reduction in the rate of cerebral glucose utilization relative to wakefulness2-4. This and other findings have led to the widely held belief that sleep serves a function related to cerebral metabolism. Yet, the mechanisms underlying the reduction in cerebral glucose metabolism during NREMS remain to be elucidated.
	One phenomenon associated with NREMS that might impact cerebral metabolic rate is the occurrence of slow waves, oscillations at frequencies less than 4 Hz, in the electroencephalogram5,6. These slow waves detected at the level of the skull or cerebral cortical surface reflect the oscillations of underlying neurons between a depolarized/up state and a hyperpolarized/down state7. During the down state, cells do not undergo action potentials for intervals of up to several hundred milliseconds. Restoration of ionic concentration gradients subsequent to action potentials represents a significant metabolic load on the cell8; absence of action potentials during down states associated with NREMS may contribute to reduced metabolism relative to wake.
	Two technical challenges had to be addressed in order for this hypothetical relationship to be tested. First, it was necessary to measure cerebral glycolytic metabolism with a temporal resolution reflective of the dynamics of the cerebral EEG (that is, over seconds rather than minutes). To do so, we measured the concentration of lactate, the product of aerobic glycolysis, and therefore a readout of the rate of glucose metabolism in the brains of mice. Lactate was measured using a lactate oxidase based real time sensor embedded in the frontal cortex. The sensing mechanism consists of a platinum-iridium electrode surrounded by a layer of lactate oxidase molecules. Metabolism of lactate by lactate oxidase produces hydrogen peroxide, which produces a current in the platinum-iridium electrode. So a ramping up of cerebral glycolysis provides an increase in the concentration of substrate for lactate oxidase, which then is reflected in increased current at the sensing electrode. It was additionally necessary to measure these variables while manipulating the excitability of the cerebral cortex, in order to isolate this variable from other facets of NREMS.
	We devised an experimental system for simultaneous measurement of neuronal activity via the elecetroencephalogram, measurement of glycolytic flux via a lactate biosensor, and manipulation of cerebral cortical neuronal activity via optogenetic activation of pyramidal neurons. We have utilized this system to document the relationship between sleep-related electroencephalographic waveforms and the moment-to-moment dynamics of lactate concentration in the cerebral cortex. The protocol may be useful for any individual interested in studying, in freely behaving rodents, the relationship between neuronal activity measured at the electroencephalographic level and cellular energetics within the brain.

A procedure is described for manipulating the activity of cerebral cortical pyramidal neurons optogenetically while the electroencephalogram, electromyogram, and cerebral lactate concentration are monitored. Experimental recordings are performed on cable-tethered mice while they undergo spontaneous sleep/wake cycles. Optogenetic equipment is assembled in our laboratory; recording equipment is commercially available.

Electroencefalografía simultánea, en tiempo real Medición de la concentración de lactato y Manipulación optogenético de la actividad neuronal en la corteza cerebral de roedores

Although the brain represents less than 5% of the body  by mass, it utilizes approximately one quarter of the glucose used by the body  at rest1. The ...

A Comprehensive Protocol for Manual Segmentation of the Medial Temporal Lobe Structures

The present paper describes a comprehensive protocol for manual tracing of the set of brain regions comprising the medial temporal lobe (MTL): amygdala, hippocampus, and the associated parahippocampal regions (perirhinal, entorhinal,&#160;and parahippocampal proper). Unlike most other tracing protocols available, typically focusing on certain MTL areas (e.g., amygdala and/or hippocampus), the integrative perspective adopted by the present tracing guidelines allows for clear localization of all MTL subregions. By integrating information from a variety of sources, including extant tracing protocols separately targeting various MTL structures, histological reports, and brain atlases, and with the complement of illustrative visual materials, the present protocol provides an accurate, intuitive, and convenient guide for understanding the MTL anatomy. The need for such tracing guidelines is also emphasized by illustrating possible differences between automatic and manual segmentation protocols. This knowledge can be applied toward research involving not only structural MRI investigations but also structural-functional colocalization and fMRI signal extraction from anatomically defined ROIs, in healthy and clinical groups alike.

The present work provides a comprehensive set of guidelines for manually tracing the medial temporal lobe (MTL) structures. This protocol can be applied to research involving structural and/or combined structural-functional magnetic resonance imaging (MRI) investigations of the MTL, in both healthy and clinical groups.

Un protocolo integral para la segmentación manual de las estructuras mediales Temporal Lobe

The present paper describes a comprehensive protocol for manual tracing of the set of brain regions comprising the medial temporal lobe (MTL): amygdala, ...

Preparation of Acute Brain Slices Using an Optimized N-Methyl-D-glucamine Protective Recovery Method

This protocol is a practical guide to the N-methyl-D-glucamine (NMDG) protective recovery method of brain slice preparation. Numerous recent studies have validated the utility of this method for enhancing neuronal preservation and overall brain slice viability. The implementation of this technique by early adopters has facilitated detailed investigations into brain function using diverse experimental applications and spanning a wide range of animal ages, brain regions, and cell types. Steps are outlined for carrying out the protective recovery brain slice technique using an optimized NMDG artificial cerebrospinal fluid (aCSF) media formulation and enhanced procedure to reliably obtain healthy brain slices for patch clamp electrophysiology. With this updated approach, a substantial improvement is observed in the speed and reliability of gigaohm seal formation during targeted patch clamp recording experiments while maintaining excellent neuronal preservation, thereby facilitating challenging experimental applications. Representative results are provided from multi-neuron patch clamp recording experiments to assay synaptic connectivity in neocortical brain slices prepared from young adult transgenic mice and mature adult human neurosurgical specimens. Furthermore, the optimized NMDG protective recovery method of brain slicing is compatible with both juvenile and adult animals, thus resolving a limitation of the original methodology. In summary, a single media formulation and brain slicing procedure can be implemented across various species and ages to achieve excellent viability and tissue preservation.

Preparation of Acute Brain Slices Using an Optimized N-Methyl-D-glucamine Protective Recovery Method

This protocol demonstrates the implementation of an optimized N-methyl-D-glucamine (NMDG) protective recovery method of brain slice preparation. A single media formulation is used to reliably obtain healthy brain slices from animals of any age and for diverse experimental applications.

Preparación de rebanadas cerebrales agudas mediante un optimizado N-metil-D-glucamine recuperación protección método

This protocol is a practical guide to the N-methyl-D-glucamine (NMDG) protective recovery method of brain slice preparation. Numerous recent studies have ...

The Preparation of Oblique Spinal Cord Slices for Ventral Root Stimulation

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to network properties. We show how to prepare viable oblique slices of the spinal cord of young mice (P2 - P11). In this preparation, the motoneurons retain&#160;their axons coming out from the ventral roots of the&#160;spinal cord. Stimulation of these axons elicits back-propagating action potentials invading the motoneuron&#160;somas and exciting the motoneuron&#160;collaterals within the spinal cord. Recording of antidromic action potentials is an immediate, definitive and elegant way to characterize motoneuron identity, which surpasses&#160;other identification methods. Furthermore, stimulating the motoneuron collaterals is a simple and reliable way to excite the collateral targets of the motoneurons within the spinal cord, such as other motoneurons or Renshaw cells. In this protocol, we present antidromic recordings from the motoneuron somas as well as Renshaw cell excitation, resulting from ventral root stimulation.

We show how to prepare oblique slices of the spinal cord in young mice. This preparation allows for the stimulation of the ventral roots.

La Preparación de oblicua de la médula espinal ventral de segmentos para Root Estimulación

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to ...

Effects of Transcranial Alternating Current Stimulation on the Primary Motor Cortex by Online Combined Approach with Transcranial Magnetic Stimulation

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific frequency and in turn modulate ongoing cortical oscillatory activity. This neurotool allows the establishment of a causal link between endogenous oscillatory activity and behavior. Most of the tACS studies have shown online effects of tACS. However, little is known about the underlying action mechanisms of this technique because of the AC-induced artifacts on Electroencephalography (EEG) signals. Here we show a unique approach to investigate online physiological frequency-specific effects of tACS of the primary motor cortex (M1) by using single pulse Transcranial Magnetic Stimulation (TMS) to probe cortical excitability changes. In our setup, the TMS coil is placed over the tACS electrode while Motor Evoked Potentials (MEPs) are collected to test the effects of the ongoing M1-tACS. So far, this approach has mainly been used to study the visual and motor systems. However, the current tACS-TMS setup can pave the way for future investigations of cognitive functions. Therefore, we provide a step-by-step manual and video guidelines for the procedure.

Transcranial Alternating Current Stimulation (tACS) allows the modulation of cortical excitability in a frequency-specific fashion. Here we show a unique approach which combines online tACS with single pulse Transcranial Magnetic Stimulation (TMS) in order to "probe" cortical excitability by means of Motor Evoked Potentials.

Efectos de la corriente alterna la estimulación transcraneal en la corteza de Motor primaria por Online enfoque combinado con la estimulación magnética transcraneal

Transcranial Alternating Current Stimulation (tACS) is a neuromodulatory technique able to act through sinusoidal electrical waveforms in a specific ...

Evaluation of Synapse Density in Hippocampal Rodent Brain Slices

In the brain, synapses are specialized junctions between neurons, determining the strength and spread of neuronal signaling. The number of synapses is tightly regulated during development and neuronal maturation. Importantly, deficits in synapse number can lead to cognitive dysfunction. Therefore, the evaluation of synapse number is an integral part of neurobiology. However, as synapses are small and highly compact in the intact brain, the assessment of absolute number is challenging. This protocol describes a method to easily identify and evaluate synapses in hippocampal rodent slices using immunofluorescence microscopy. It includes a three-step procedure to evaluate synapses in high-quality confocal microscopy images by analyzing the co-localization of pre- and postsynaptic proteins in hippocampal slices. It also explains how the analysis is performed and gives representative examples from both excitatory and inhibitory synapses. This protocol provides a solid foundation for the analysis of synapses and can be applied to any research investigating the structure and function of the brain.

A protocol for accurately identifying and analyzing synapses in hippocampal slices using immunofluorescence is outlined in this article.

Evaluación de la densidad de sinapsis en rebanadas de hipocampo cerebral de roedor

In the brain, synapses are specialized junctions between neurons, determining the strength and spread of neuronal signaling. The number of synapses is ...

Preparation of Rhythmically-active In Vitro Neonatal Rodent Brainstem-spinal Cord and Thin Slice

Mammalian inspiratory rhythm is generated from a neuronal network in a region of the medulla called the preB&#246;tzinger complex (pBC), which produces a signal driving the rhythmic contraction of inspiratory muscles. Rhythmic neural activity generated in the pBC and carried to other neuronal pools to drive the musculature of breathing may be studied using various approaches, including en bloc nerve recordings and transverse slice recordings. However, previously published methods have not extensively described the brainstem-spinal cord dissection process in a transparent and reproducible manner for future studies. Here, we present a comprehensive overview of a method used to reproducibly cut rhythmically-active brainstem slices containing the necessary and sufficient neuronal circuitry for generating and transmitting inspiratory drive. This work builds upon previous brainstem-spinal cord electrophysiology protocols to enhance the likelihood of reliably obtaining viable and rhythmically-active slices for recording neuronal output from the pBC, hypoglossal premotor neurons (XII pMN), and hypoglossal motor neurons (XII MN). The work presented expands upon previous published methods by providing detailed, step-by-step illustrations of the dissection, from whole rat pup, to in vitro slice containing the XII rootlets.

This protocol both visually communicates the brainstem-spinal cord preparation and clarifies the preparation of brainstem transverse slices in a comprehensive step-by-step manner. It was designed to increase reproducibility and enhance the likelihood of obtaining viable, long lasting, rhythmically-active slices for recording neural output from the respiratory regions of the brainstem.

Preparación de rítmicamente activa en Vitro Neonatal roedor del médula oblonga-medulares y rebanada fina

Mammalian inspiratory rhythm is generated from a neuronal network in a region of the medulla called the preB&#246;tzinger complex (pBC), which produces a ...