Ambre Southwell mis en place l&#39;appareil et formé les auteurs dans son utilisation. Le financement a été fourni par une subvention du NINDS à Paul Patterson.

1. Ce protocole est basé sur ceux de Southwell et al. al. (2009) et Carter et al. al. (2001). <ol><li> L&#39;appareil à faisceau se compose de 1 mètre de poutres avec une surface plane de 12 mm ou 6 mm de largeur) au repos 50 cm au dessus du plateau de table sur les deux pôles. Une boîte noire est placée à l&#39;extrémité de la poutre comme le point d&#39;arrivée. (Contreplaqués et d&#39;autres types de bois pour les poutres, les poteaux, et la boîte se trouve la plupart des quincailleries). Matériaux de nidification des cages à domicile est placé dans la boîte noire pour attirer les souris sur le point d&#39;arrivée. Une lampe (avec ampoule 60 watts) est utilisé pour faire la lumière au-dessus du point de départ et sert un stimulus aversif. Le temps de traverser le centre de 80 cm est mesurée par deux détecteurs de mouvement (fabriqué par Visopia): une à 0 cm qui démarre une minuterie et un à 80 cm qui arrête le chronomètre. Un hamac en nylon (qui peut être obtenu à partir d&#39;un magasin de tissu local) est tendue en dessous de la poutre, ~ 7,5 cm au-dessus de la table, afin d&#39;amortir les chutes. Une caméra vidéo est fixée sur un trépied pour enregistrer les performances. L&#39;appareil utilisé dans cette démonstration a été construit sur le site. </li><li> Une cohorte d&#39;au moins 10 souris pour chaque condition est recommandé pour ce test. Les souris sont logées en tant que groupes, si possible, dans une lumière 12 heures (7 heures-19 heures) cycle jour / nuit et acclimatés dans leur cage dans l&#39;installation de comportement pendant au moins 2 semaines avant le début du test. Environ 10 minutes avant l&#39;entraînement / test, la souris peut être transporté à la salle contenant l&#39;appareil à faisceau. </li><li> Les jours d&#39;entraînement, chaque souris traverse le faisceau de 12 mm 3 fois, puis le faisceau de 6 mm à 3 reprises. Des faisceaux de grandes largeurs (soit 28 mm) peut être utilisé pour les souris qui ne sont pas capables de traverser les plus étroites ou pour les grandes souris. Les souris sont placées à une extrémité d&#39;une poutre et le temps nécessaire à traverser pour échapper à la boîte à l&#39;autre bout (80 cm) est mesurée par les détecteurs de mouvement. Le temporisateur est démarré par le nez de la souris entrer dans le centre de 80 cm, et arrêté lorsque l&#39;animal arrive à la fin des années 80 cm. Le reste des souris pendant 10 min dans leurs cages à domicile entre les séances de formation sur les deux faisceaux. Durant cette période intertrial, une autre souris 3-4 peuvent être formés pour faire un usage efficace du temps. Souris C57BL / 6 généralement traverser la poutre avec une quantité minime d&#39;arrêter ou de décrochage. Cependant, quand ils ne décrochage, renifler ou de regarder autour, sans procédure de l&#39;avant, l&#39;enquêteur doit encourager la souris pour continuer à aller de l&#39;avant par aiguillonner, piquer, ou en le poussant par derrière avec les doigts gantés. Une fois que les souris sont dans le coffre, ils sont autorisés un certain temps (~ 15 secondes) pour s&#39;y reposer avant la prochaine épreuve. Après chaque séance d&#39;entraînement, les souris sont retournés directement à leurs cages à domicile et ramené dans leur chambre de logement. Fait à noter, les souris peuvent décrochage plus si elles sont plus formés et devenus trop familiers avec la tâche et l&#39;appareil. D&#39;autre part, la formation peut être poursuivie pour des journées supplémentaires si la souris ne sont toujours pas traverser la totalité du faisceau avec succès après 2 jours de formation. Si les traitements sont appliqués à la souris, une mesure de référence de la performance doit être obtenue avant le traitement. </li><li> Le jour du test, le temps de traverser chaque faisceau sont enregistrées. Deux essais fructueux dans lequel la souris n&#39;a pas décroché sur la poutre sont moyennées. Les enregistrements vidéo peuvent être utilisés pour une analyse plus fine de glissement et d&#39;autres déficits moteurs observables. Une autre façon d&#39;évaluer la marche du faisceau est par un système de notation 1,2 neurologiques, dont les taux de l&#39;incapacité à traverser le faisceau comme un score de &quot;1&quot; et la capacité de traverser le faisceau normalement avec les deux pattes sur la surface du faisceau et moins deux fiches de pied comme un &quot;7&quot;. Un glissement est défini comme le pied venant du haut de la poutre. Dans ce système d&#39;indexation, un score de «3» correspondrait à traverser le faisceau en faisant glisser les membres. Un animal qui marque 1 sur deux essais n&#39;est pas retesté. Description de la performance sur la poutre liées à des scores d&#39;autres peuvent être trouvés dans Feeney et al., (1982) et Carter et coll., (2001). </li><li> Les poutres et la boîte sont nettoyés des excréments de souris et essuyé avec des serviettes imbibées d&#39;éthanol à 70%, puis l&#39;eau avant de la poutre suivant est placé sur l&#39;appareil. </li></ol> 2. Les résultats représentatifs: <img src="/files/ftp_upload/2376/2376fig1.jpg" alt="Figure 1" /> Figure 1. Typique à croix de C57BL6 mâles et femelles sur des poutres de 6mm et 12mm. Une cohorte de 9 à 11 semaines vieilles souris WT C57BL/6-NCRL ont été testées sur les deux faisceaux après 2 jours de formation. Délais moyens pour traverser le faisceau de 12 mm ont été de 4,6 ± 0,4 sec pour les mâles (n = 14) et 3,3 ± 0,3 sec pour les femelles (n = 11). Fois sur la poutre 6 mm ont été de 6,8 ± 0,7 sec pour les mâles (n = 13) et 5,9 ± 0,5 sec pour les femelles (n = 10) (les erreurs sont signalés comme MEB).

<ol>
	<li>Feeney, D. M., Gonzalez, A., Law, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphetamine,+haloperidol,+and+experience+interact+to+affect+rate+of+recovery+after+motor+cortex+injury.">Amphetamine, haloperidol, and experience interact to affect rate of recovery after motor cortex injury.</a> Science. 217, 855-857 (1982).</li><li>Carter, R. J., Morton, J., Dunnett, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor+coordination+and+balance+in+rodents.">Motor coordination and balance in rodents.</a> Curr Protoc Neurosci. Chapter 8, (2001).</li><li>Wallace, J. E., Krauter, E. E., Campbell, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor+and+reflexive+behavior+in+the+aging+rat.">Motor and reflexive behavior in the aging rat.</a> J Gerontol. 35, 364-370 (1980).</li><li>Brooks, S. P., Dunnett, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tests+to+assess+motor+phenotype+in+mice:+a+user's+guide.">Tests to assess motor phenotype in mice: a user's guide.</a> Nat Rev Neurosci. 10, 519-529 (2009).</li><li>Fox, G. B., Fan, L., Levasseur, R. A., Faden, A. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sustained+sensory/motor+and+cognitive+deficits+with+neuronal+apoptosis+following+controlled+cortical+impact+brain+injury+in+the+mouse.">Sustained sensory/motor and cognitive deficits with neuronal apoptosis following controlled cortical impact brain injury in the mouse.</a> J Neurotrauma. 15, 599-614 (1998).</li><li>Buccafusco, 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=.">.</a> Methods of behavioral analysis in neuroscience. , (2009).</li><li>Southwell, A. L., Ko, J., Patterson, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrabody+gene+therapy+ameliorates+motor,+cognitive,+and+neuropathological+symptoms+in+multiple+mouse+models+of+Huntington's+disease.">Intrabody gene therapy ameliorates motor, cognitive, and neuropathological symptoms in multiple mouse models of Huntington's disease.</a> J Neurosci. 29, 13589-13602 (2009).</li><li>Carter, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+progressive+motor+deficits+in+mice+transgenic+for+the+human+Huntington's+disease+mutation.">Characterization of progressive motor deficits in mice transgenic for the human Huntington's disease mutation.</a> J Neurosci. 19, 3248-3257 (1999).</li><li>Gulinello, M., Chen, F., Dobrenis, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+deficits+in+motor+coordination+and+cognitive+dysfunction+in+a+mouse+model+of+the+neurodegenerative+lysosomal+storage+disorder,+Sandhoff+disease.">Early deficits in motor coordination and cognitive dysfunction in a mouse model of the neurodegenerative lysosomal storage disorder, Sandhoff disease.</a> Behav Brain Res. 193, 315-319 (2008).</li><li>Stanley, J. 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+mouse+beam+walking+assay+offers+improved+sensitivity+over+the+mouse+rotarod+in+determining+motor+coordination+deficits+induced+by+benzodiazepines.">The mouse beam walking assay offers improved sensitivity over the mouse rotarod in determining motor coordination deficits induced by benzodiazepines.</a> J Psychopharmacol. 19, 221-227 (2005).</li></ol>

Expériences sur les animaux ont été effectuées en conformité avec les directives et règlements établis par les soins des animaux Caltech institutionnels et le Comité d&#39;utilisation (IACUC).

Performance à la poutre est une mesure utile de la coordination fine et l&#39;équilibre et a été validé par des travaux antérieurs. Le test du faisceau permet de détecter des déficits moteurs en raison de l&#39;âge, le syst `nerveux central des lésions, et les manipulations génétiques et pharmacologiques chez les jeunes rongeurs et plus 2,3,4. Souris avec des lésions corticales présentent souvent l&#39;impact controlatéral glisser sur le faisceau 5,6. Le test du faisceau a également...

<ul><li> Poutres: 1-m des bandes de bois lisse avec des carrés de petites, moyennes et grandes entreprises (à savoir, 6, 12 et 28 mm de large) des sections </li><li> Soutien à tenir debout jusqu&#39;à la section de démarrage de la poutre en relief (~ 1,5 cm de section, 50 cm de haut) </li><li> Objectif boîte (20 cm de chaque côté), monté sur un support (3 cm de section, 50 cm de haut) </li><li> Hamac-~ 7,5 cm au-dessus de table </li><li> 60-watt (W) Lampe de bureau </li><li> Caméra vidéo, un trépied, et des cassettes vidéo vierge </li><li> L&#39;éthanol, serviettes en papier, produits de nettoyage </li></ul>

assessment of motor balance and coordination in mice using the balance beam

Les lésions cérébrales, les manipulations génétiques, et les traitements pharmacologiques peuvent entraîner des altérations de la motricité chez les souris. Coordination motrice fine et l&#39;équilibre peut être évaluée par le test de marche de faisceau. Le but de ce test est pour la souris pour rester debout et marcher à travers un faisceau étroit élevés à une plateforme sûre. Ce test se déroule sur 3 jours consécutifs: 2 jours de formation et 1 journée d&#39;essais. Performance sur la poutre est quantifié en mesurant le temps qu&#39;il faut pour que la souris pour traverser le faisceau et le nombre de bulletins de patte qui se produisent dans le processus. Nous rapportons ici le protocole utilisé dans notre laboratoire, et des résultats représentatifs à partir d&#39;une cohorte de souris C57BL / 6. Cette tâche est particulièrement utile pour détecter des déficits subtils dans la motricité et l&#39;équilibre qui peut ne pas être détectés par les tests du moteur, telles que l&#39;Rotarod.

Watch this Scientific Journal Video about Assessment of Motor Balance and Coordination in Mice using the Balance Beam at JoVE.com

Assessment of Motor Balance and Coordination in Mice using the Balance Beam

Les déficits de la coordination motrice fine peut être évaluée avec le test de poutre d&#39;équilibre. Performance sur la poutre est quantifiée par la vitesse à laquelle le faisceau est traversée et le nombre de fois que la souris glisse sur la poutre.

Évaluation du bilan du moteur et de la coordination des souris en utilisant la poutre d&#39;équilibre

Brain injury, genetic manipulations, and pharmacological treatments can result in alterations of motor skills in mice.  Fine motor coordination and ...

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46.0K vues.  California Institute of Technology. Les déficits de la coordination motrice fine peut être évaluée avec le test de poutre d'équilibre. Performance sur la poutre est quantifiée par la vitesse à laquelle le faisceau est traversée et le nombre de fois que la souris glisse sur la poutre.

Vidéo: Assessment of Motor Balance and Coordination in Mice using the Balance Beam

Measuring Motor Coordination in Mice

Mice are increasingly being used in behavioral neuroscience, largely replacing rats as the behaviorist's animal of choice. Before aspects of behavior such as emotionality or cognition can be assessed, however, it is vital to determine whether the motor capabilities of e.g. a mutant or lesioned mouse allow such an assessment. Performance on a maze task requiring strength and coordination, such as the Morris water maze, might well be impaired in a mouse by motor, rather than cognitive, impairments, so it is essential to selectively dissect the latter from the former. For example, sensorimotor impairments caused by NMDA antagonists have been shown to impair water maze performance2. 
Motor coordination has traditionally been assessed in mice and rats by the rotarod test, in which the animal is placed on a horizontal rod that rotates about its long axis; the animal must walk forwards to remain upright and not fall off. Both set speed and accelerating versions of the rotarod are available.
The other three tests described in this article (horizontal bar, static rods and parallel bars) all measure coordination on static apparatus. The horizontal bar also requires strength for adequate performance, particularly of the forelimbs as the mouse initially grips the bar just with the front paws. 
Adult rats do not perform well on tests such as the static rods and parallel bars (personal observations); they appear less well coordinated than mice. I have only tested male rats, however, and male mice seem generally less well coordinated than females. Mice appear to have a higher strength:weight ratio than rats; the Latin name, Mus musculus, seems entirely appropriate. The rotarod, the variations of the foot fault test12 or the Catwalk (Noldus)15 apparatus are generally used to assess motor coordination in rats.

Protocols are presented for two established motor coordination tasks, the accelerating rotarod and horizontal bar, also two tests developed in Oxford recently, the static rods and parallel bars. These tests can detect motor impairments potentially of interest in their own right, as well as being possible variables in tests of other areas of behavior.

Mesure de la coordination motrice chez la souris

Mice are increasingly being used in behavioral neuroscience, largely replacing rats as the behaviorist's animal of choice. Before aspects of behavior such ...

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Neurosciences

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities

Opioid-induced hyperalgesia and tolerance severely impact the clinical efficacy of opiates as pain relievers in animals and humans. The molecular mechanisms underlying both phenomena are not well understood and their elucidation should benefit from the study of animal models and from the design of appropriate experimental protocols. 
We describe here a methodological approach for inducing, recording and quantifying morphine-induced hyperalgesia as well as for evidencing analgesic tolerance, using the tail-immersion and tail pressure tests in wild-type mice. As shown in the video, the protocol is divided into five sequential steps. Handling and habituation phases allow a safe determination of the basal nociceptive response of the animals. Chronic morphine administration induces significant hyperalgesia as shown by an increase in both thermal and mechanical sensitivity, whereas the comparison of analgesia time-courses after acute or repeated morphine treatment clearly indicates the development of tolerance manifested by a decline in analgesic response amplitude. This protocol may be similarly adapted to genetically modified mice in order to evaluate the role of individual genes in the modulation of nociception and morphine analgesia. It also provides a model system to investigate the effectiveness of potential therapeutic agents to improve opiate analgesic efficacy.

We describe a protocol to examine the development of opioid-induced hyperalgesia and tolerance in mice. Based on the measurement of thermal and mechanical nociceptive responses of na&#239;ve and morphine-treated animals, it allows to quantify the increase in pain sensitivity (hyperalgesia) and decrease in analgesia (tolerance) associated with chronic opiate administration.

L&#39;évaluation de la tolérance induite par la morphine hyperalgésie et analgésique chez la souris utilisant thermiques et mécaniques nociceptifs modalités

Opioid-induced hyperalgesia and tolerance severely impact the clinical efficacy of opiates as pain relievers in animals and humans. The molecular ...

The Neuromuscular Junction: Measuring Synapse Size, Fragmentation and Changes in Synaptic Protein Density Using Confocal Fluorescence Microscopy

The neuromuscular junction (NMJ) is the large, cholinergic relay synapse through which mammalian motor neurons control voluntary muscle contraction. Structural changes at the NMJ can result in neurotransmission failure, resulting in weakness, atrophy and even death of the muscle fiber. Many studies have investigated how genetic modifications or disease can alter the structure of the mouse NMJ. Unfortunately, it can be difficult to directly compare findings from these studies because they often employed different parameters and analytical methods. Three protocols are described here. The first uses maximum intensity projection confocal images to measure the area of acetylcholine receptor (AChR)-rich postsynaptic membrane domains at the endplate and the area of synaptic vesicle staining in the overlying presynaptic nerve terminal. The second protocol compares the relative intensities of immunostaining for synaptic proteins in the postsynaptic membrane. The third protocol uses Fluorescence Resonance Energy Transfer (FRET) to detect changes in the packing of postsynaptic AChRs at the endplate. The protocols have been developed and refined over a series of studies. Factors that influence the quality and consistency of results are discussed and normative data are provided for NMJs in healthy young adult mice.

The neuromuscular junction (NMJ) is altered in a variety of conditions that can sometimes culminate in synaptic failure. This report describes fluorescence microscope-based methods to quantify such structural changes.

La jonction neuromusculaire: Synapse mesurer la taille, fragmentation et les changements dans Synaptic Protein densité en utilisant microscopie de fluorescence confocale

The neuromuscular junction (NMJ) is the large, cholinergic relay synapse through which mammalian motor neurons control voluntary muscle contraction. ...

Assessment of Dendritic Arborization in the Dentate Gyrus of the Hippocampal Region in Mice

Dendritic arborization has been shown to be a reliable marker for examination of structural and functional integrity of neurons. Indeed, the complexity and extent of dendritic arborization correlates well with the synaptic plasticity in these cells. A reliable method for assessment of dendritic arborization is needed to characterize the deleterious effects of neurological disorders on these structures and to determine the effects of therapeutic interventions. However, quantification of these structures has proven to be a formidable task given their complex and dynamic nature. Fortunately, sophisticated imaging techniques can be paired with conventional staining methods to assess the state of dendritic arborization, providing a more reliable and expeditious means of assessment. Below is an example of how these imaging techniques were paired with staining methods to characterize the dendritic arborization in wild type mice. These complementary imaging methods can be used to qualitatively and quantitatively assess dendritic arborization that span a rather wide area within the hippocampal region.

We describe two methods for visualization and quantification of dendritic arborization in the hippocampus of mouse models: real-time and extended depth of field imaging. While the former method allows sophisticated topographical tracing and quantification of the extent of branching, the latter allows speedy visualization of the dendritic tree.

Évaluation de l&#39;arborisation dendritique dans le gyrus denté de la région de l&#39;hippocampe chez la souris

Dendritic arborization has been shown to be a reliable marker for examination of structural and functional integrity of neurons. Indeed, the complexity ...

A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.

A novel low-cost human-machine interface for interactive post-stroke balance rehabilitation system is presented in this article. The system integrates off-the-shelf low-cost sensors towards volitionally driven electrotherapy paradigm. The proof-of-concept software interface is demonstrated on healthy volunteers.

Une machine à interface humaine Intégration de capteurs à faible coût avec un système de stimulation neuromusculaire électrique pour post-AVC Solde Réhabilitation

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing ...

Functional and Morphological Assessment of Diaphragm Innervation by Phrenic Motor Neurons

This protocol specifically focuses on tools for assessing phrenic motor neuron (PhMN) innervation of the diaphragm at both the electrophysiological and morphological levels. Compound muscle action potential (CMAP) recording following phrenic nerve stimulation can be used to quantitatively assess functional diaphragm innervation by PhMNs of the cervical spinal cord in vivo in anesthetized rats and mice. Because CMAPs represent simultaneous recording of all myofibers of the whole hemi-diaphragm, it is useful to also examine the phenotypes of individual motor axons and myofibers at the diaphragm NMJ in order to track disease- and therapy-relevant morphological changes such as partial and complete denervation, regenerative sprouting and reinnervation. This can be accomplished via whole-mount immunohistochemistry (IHC) of the diaphragm, followed by detailed morphological assessment of individual NMJs throughout the muscle. Combining CMAPs and NMJ analysis provides a powerful approach for quantitatively studying diaphragmatic innervation in rodent models of CNS and PNS disease.

Compound muscle action potential recording quantitatively assesses functional diaphragm innervation by phrenic motor neurons. Whole-mount diaphragm immunohistochemistry assesses morphological innervation at individual neuromuscular junctions. The goal of this protocol is to demonstrate how these two powerful methodologies can be used in various rodent models of spinal cord disease.

Évaluation fonctionnelle et morphologique de membrane innervation par phrénique motoneurones

This protocol specifically focuses on tools for assessing phrenic motor neuron (PhMN) innervation of the diaphragm at both the electrophysiological and ...

Assessment of Hippocampal Dendritic Complexity in Aged Mice Using the Golgi-Cox Method

Dendritic spines are the protuberances from the neuronal dendritic shafts that contain&#160; excitatory synapses. The morphological and branching variations of the neuronal dendrites within the hippocampus are implicated in cognition and memory formation. There are several approaches to Golgi staining, all of which have been useful for determining the morphological characteristics of dendritic arbors and produce a clear background. The present Golgi-Cox method, (a slight variation of the protocol that is provided with a commercial Golgi staining kit), was designed to assess how a relatively low dose of the chemotherapeutic drug 5-flurouracil (5-Fu) would affect dendritic morphology, the number of spines, and the complexity of arborization within the hippocampus. The 5-Fu significantly modulated the dendritic complexity and decreased the spine density throughout the hippocampus in a region-specific manner. The data presented show that the Golgi staining method effectively stained the mature neurons in the CA1, the CA3, and the dentate gyrus (DG) of the hippocampus. This protocol reports the details for each step so that other researchers can reliably stain tissue throughout the brain with high quality results and minimal troubleshooting.

Here we present a Golgi-Cox protocol in extensive detail. This reliable tissue stain method allows for a high-quality assessment of the cytoarchitecture in the hippocampus, and throughout the entire brain, with minimal troubleshooting.

Évaluation de la complexité dendritique de l&#39;hippocampe chez les souris vieillies utilisant la méthode de Golgi-Cox

Dendritic spines are the protuberances from the neuronal dendritic shafts that contain&#160; excitatory synapses. The morphological and branching ...

Retrograde Neuroanatomical Tracing of Phrenic Motor Neurons in Mice

Phrenic motor neurons are cervical motor neurons originating from C3 to C6 levels in most mammalian species. Axonal projections converge into phrenic nerves innervating the respiratory diaphragm. In spinal cord slices, phrenic motor neurons cannot be identified from other motor neurons on morphological or biochemical criteria. We provide the description of procedures for visualizing phrenic motor neuron cell bodies in mice, following intrapleural injections of cholera toxin subunit beta (CTB) conjugated to a fluorophore. This fluorescent neuroanatomical tracer has the ability to be caught up at the diaphragm neuromuscular junction, be carried retrogradely along the phrenic axons and reach the phrenic cell bodies. Two methodological approaches of intrapleural CTB delivery are compared: transdiaphragmatic versus transthoracic injections. Both approaches are successful and result in similar number of CTB-labeled phrenic motor neurons. In conclusion, these techniques can be applied to visualize or quantify the phrenic motor neurons in various experimental studies such as those focused on the diaphragm-phrenic circuitry.

Here, we describe a protocol for identifying phrenic motor neurons in mice after intrapleural delivery of fluorophore conjugated cholera toxin subunit beta. Two techniques are compared to inject the pleural cavity: transdiaphragmatic versus transthoracic approaches.

Traçage neuroanatomique rétrograde des motoneurones phréniques chez la souris

Phrenic motor neurons are cervical motor neurons originating from C3 to C6 levels in most mammalian species. Axonal projections converge into phrenic ...

3D Kinematic Analysis for the Functional Evaluation in the Rat Model of Sciatic Nerve Crush Injury

Compared to the Sciatic Functional Index (SFI), kinematic analysis is a more reliable and sensitive method for performing functional evaluations of sciatic nerve injury rodent models. In this protocol, we describe a novel kinematic analysis method that uses a three-dimensional (3D) motion capture apparatus for functional evaluations using a rat sciatic nerve crush injury model. First, the rat is familiarized with treadmill walking. Markers are then attached to the designated bone landmarks and the rat is made to walk on the treadmill at the desired speed. Meanwhile, the posterior limb movements of the rat are recorded using four cameras. Depending on the software used, marker tracings are created using both automatic and manual modes and the desired data are produced after subtle adjustments. This method of kinematic analysis, which uses a 3D motion capture apparatus, offers numerous advantages, including superior precision and accuracy. Many more parameters can be investigated during the comprehensive functional evaluations. This method has several shortcomings that require consideration: The system is expensive, can be complicated to operate, and may produce data deviations due to skin shifting. Nevertheless, kinematic analysis using a 3D motion capture apparatus is useful for performing functional anterior and posterior limb evaluations. In the future, this method may become increasingly useful for generating accurate assessments of various traumas and diseases.

We introduce a kinematic analysis method that uses a three-dimensional motion capture apparatus containing four cameras and data processing software for performing functional evaluations during fundamental research involving rodent models.

Analyse cinématique 3D pour l’évaluation fonctionnelle dans le modèle de rat de la blessure d’écrasement de nerf sciatique

Compared to the Sciatic Functional Index (SFI), kinematic analysis is a more reliable and sensitive method for performing functional evaluations of ...

Laser-Induced Brain Injury in the Motor Cortex of Rats

A common technique for inducing stroke in experimental rodent models involves the transient (often denoted as MCAO-t) or permanent (designated as MCAO-p) occlusion of the middle cerebral artery (MCA) using a catheter. This generally accepted technique, however, has some limitations, thereby limiting its extensive use. Stroke induction by this method is often characterized by high variability in the localization and size of the ischemic area, periodical occurrences of hemorrhage, and high death rates. Also, the successful completion of any of the transient or permanent procedures requires expertise and often lasts for about 30 minutes. In this protocol, a laser irradiation technique is presented that can serve as an alternative method for inducing and studying brain injury in rodent models.
When compared to rats in the control and MCAO groups, the brain injury by laser induction showed reduced variability in body temperature, infarct volume, brain edema, intracranial hemorrhage, and mortality. Furthermore, the use of a laser-induced injury caused damage to the brain tissues only in the motor cortex unlike in the MCAO experiments where destruction of both the motor cortex and striatal tissues is observed.
Findings from this investigation suggest that laser irradiation could serve as an alternative and effective technique for inducing brain injury in the motor cortex. The method also shortens the time for completing the procedure and does not require expert handlers.

The protocol presented here shows a technique to create a rodent model of brain injury. The method described here uses laser irradiation and targets motor cortex.

Lésion cérébrale induite au laser dans le cortex moteur des rats

A common technique for inducing stroke in experimental rodent models involves the transient (often denoted as MCAO-t) or permanent (designated as MCAO-p) ...