Biz bu deneysel teknikler geliştirilmesi sırasında teknik girdi sağlamak için Dr. Dan Green teşekkür ederim. Bu çalışma NIH Hibe R01-EY016849A ve Smith Aile Yeni Araştırmacı Ödülü tarafından desteklenmiştir.

Bölüm I: Tungsten-Cam Elektrotlar Fabrikasyon <ol><li> Grafit halka sodyum nitrat (0.71g/mL) ve potasyum hidroksit (0.34g/mL) 1 su içinde çözünmüş konsantre solüsyonu ile dolu bir behere konur ve beher değiştirilmiş bir dikiş makinesi dikiş kol altına yerleştirilir . </li><li> Tungsten tel (0,5 mm çap, 6cm uzunluğunda) kısmen çözüm (1-2cm) batırılır, böylece dikiş koluna bantlanmış. </li><li> 2V grafit halka dikiş kol ve olumsuz bir kurşun olumlu bir kurşun takarak tungsten tel üzerinden uygulanır. </li><li> Dikiş makinesi açık ve tungsten tel elektrolitik metal sivri etches 2 dakika için ~ 4Hz bir oranda çözüm tekrarlayan daldırılır. </li><li> Kazınmış tel manuel mikromanipülatör ve mikroskobik cam bir pipet (0.25mm OD, 0.175mm ID), bir bardak çektirmesi ile 1mm ucu çekti mil ile rehberlik (40x büyütme) altında dizilen noktası üzerine yerleştirilir. Tel yerleştirilmesi sırasında hareket etmesini önlemek için, cam, macun ile mikroskop aşamasında geçici olarak güvence altına alınmıştır. </li><li> Dikkatli bir mil aşağı tel, cam unpulled ucunu gelişmiş, ve 1 mikrona kadar açıklıktan küçük bir cam parçası, cam, tungsten sıkı bir uyum gösteren video ucu koparak görülür. 5-10mm çevresinde tel sıçan fiber optik kayıtlar için ipucu ötesine uzatmak gerekir. </li><li> Siyanoakrilat cam unpulled sonuna kadar uygulanır ve sonra elektrik empedansı 1M elektrotlar genellikle en iyi çalışmalarınızı sertleşme ölçülür. </li></ol> Bölüm II: Stereotaksik Kurulum ve Spike Tren Kayıtlar <ol><li> Uyaran ekranı, video sistemi, konumlandırma ve beyin içine elektrod düşürücü stereotaksik aparatı ve Microdrive birlikte gösterilmiştir. </li><li> Retina başak tren kayıtlarını gerçekleştirmek için sıçan anestezi ve daha sonra felç. Standart işlemleri (resimli), cerrahi, ilaç dağıtım ve felç sırasında mekanik ventilasyon trakeal kanül (Y-tüp) için femoral ven kanül yerleştirilmesi için kullanılır. Deneyler, hayvan için terminal. </li><li> Hazırlık süreçlerini sonra, hayvan ısıtma battaniye konur ve baş, kulak ve diş barlar ile sıçan beyin atlası 2 tarafından tanımlandığı gibi, stereotaksik konuma sabittir . </li><li> Rektal prob eklenir, 37 vücut ısısını korur bir homeothermic kontrol ünitesi ° C ile ısıtma battaniye kontrol </li><li> Metal iğne, elektrokardiyogram ve monitör kalp hızı ölçmek için neden olarak kullanılır. </li><li> Cilt kafatasının üstüne açılır ve kafatası plakaları kesiştiği (bregma) maruz kalmaktadır. Özel tasarımlı ızgaraya çerçeve yerine, bir daire ve üst direğin bir delikten begma çevresindeki kafatası üzerinde işaretlenmiş ve enine geçici olarak kaldırılır. </li><li> Stereotaksik bregma üzerinde kılavuz iğne konumlandırma sistemi kalibre edilir. 5 mm delik işaretli yerde kafatası delinmiş ve kemik, beyin açığa çıkarılır. Macunu ince bir halka yerleştirin sıfırlanır enine, delik etrafında bir mühür formu kafatası açılış etrafında yer almaktadır. </li><li> Hayvan süre için anestezi istikrarlı bir uçak varsa, veri toplama sırasında göz hareketlerini önlemek amacıyla paralitik ile enjekte edilir. Sonra hayvan mekanik ventilasyon solunum durur. Özel bir program deney boyunca havalandırma ve fizyolojik parametrelerini izler ve normal seviyelere dışında herhangi bir parametre gitmeli telafi edici eylem ihtiyaç duyulması halinde, deneyci bilgilendirir. </li><li> Kılavuz iğne tungsten elektrot ile backloaded ve beyin içine indirdi. Beyin penetrasyon sonra enine delik agar (gösterilmemiştir) ile doludur ve Microdrive montaj, mekanik stabilite için üst direğe bağlanarak. Tungsten elektrot ucu optik kiazma bulunan kafatası, aşağıdaki 8-9mm kadar sonra yavaş yavaş gelişmiş kılavuz iğne dışarı (2μm/sec). </li><li> Spike retina ganglion hücrelerinin ait trenler görsel girişine tepki tanımlanır. Tek bir fiber optik izolasyon üzerine kaydedilen hücrenin alıcı alan görsel alanı eşleştirilir ve tepki özellikleri sürüklenen ızgaralar veya ilgi diğer görsel kalıpları ile karakterizedir. Tek birim kayıtları için birkaç saat 3 sistemin istikrarı sağlar. </li></ol> Malzemeler Yetişkin Brown-Norveç sıçan (250-400g), ticari bir satıcıdan satın alınan ve regüle (12/12) aydınlık / karanlık döngüsü altında alır. Anestezi ketamin hidroklorür ve ksilizin (70 ve 2 mg / kg, sırasıyla, Henry Schein Inc) intraperitoneal enjeksiyonu ile indüklenen ve exper süre için muhafaza edildituzlu dekstroz ile karışık bir kateter aracılığı ile intravenöz ketamin ve ksilizin infüzyon (30 ve 1 mg / kg / saat) ve gallamine triethiodide (40 mg / kg / saat, Fischer A.Ş.) (0.13mm OD, Küçük Parça A.Ş. ile iment sağ femoral ven). Gallamine karışımı göz hareketleri felç dahildir. (TEFE A.Ş.) pompa infüzyon hızı, kalp hızı ve kan basıncı değişkenliği ile değerlendirilen anestezi istikrarlı bir düzlemde korumak için gerektiği şekilde ayarlandı. Felç sonra, hayvan mekanik end-tidal CO 2 &#39;in-line ile ölçülen korumak için gerekli olarak ayarlanır oranı ile 60-80 solunum / dk (2CC hacmi) (Harvard Apparatus, Model 683) trakeal kanül aracılığı ile havalandırılan oldu capnometer (Novametrix Inc Model 710Sp)% 30 oranında. Vücut ısısı homeothermic battaniye kontrol sistemi (Harvard Apparatus Inc) ile düzenlenmiştir. Vücut ısısı, end-tidal CO 2, kalp hızı ve kan basıncı sürekli bir LABVIEW program tarafından deneme boyunca takip edildi. Görsel uyaranlara 800x600 piksel çözünürlüğe sahip 100 Hz hızında çalışan bir Sony Multiscan 17e CRT monitör (30 cd / m 2 parlaklık anlamına) sunuldu. Veri toplama ve monitör çıkışı bir video görüntü işlemcisi (Cambridge Araştırma Sistemleri A.Ş., Bit + +) ve Psikofizik Toolbox 4 ile birlikte Matlab ve LabView yazılmış özel bir yazılım ile kontrol altına alındı ​​. Hayvan kontakt lensler (Oküler Instruments Inc) üzerinden 16,5 cm mesafe uyaran ekran (40,4 x 30,2 cm) görülüyor ve oftalmik solüsyon deney sırasında gözleri nemli tutmak için periyodik olarak uygulandı. Stimülasyonu için görme alanı (Stoelting Co) yüzen bir tablo (TMC A.Ş.) yüzey üzerinde yükselmiş 14cm stereotaksik aparat hayvan montaj ve birlikte masaya taşınan özel tasarlanmış kızak üzerindeki monitör ayarı ters büyütülmeden burun hakkında ± 100 derece ark. Bu 60 derece yukarıda ve 35 derece göz seviyesinin altında ve ± 42 derece yanal monitör merkezinden genişletilmiş bir yerini değiştirebilirler ekran alanı sağladı. Tungsten electodes cam ucu şeklini Küçük Parça A.Ş. ve Friedrich ve Dimmock Inc standart bir micropippete çektirmesi (Sutter Instruments, Model P-97) elde edilen özel borosilikat camdan elde edilen tel ile imal edildi. Elektrot empedansı test Bak-Elektronik satın alınmıştır. Elektrotlar motorlu Microdrive sistemi ile gelişmiş (Newport Inc StepperMike). Elektrokardiyogram ve optik sinir sinyallerinin yüksek empedans girişli bir multielectrode amplifikatör (FHC A.Ş., X-Cell 3x4) ile amplifiye ve süzülür. Kalp atım bir pencere discriminator (TEFE Inc Model 121) ile tespit edildi. Sinir aksiyon potansiyeli 0,1 ms çözünürlüğe sahip bir dijital başak discriminator (FHC A.Ş., APM) tarafından algılanır ve zaman damgalı. Başak başak kez uyaran kilitli olduğunu, böylece video görüntü işlemcisi, bir tetikleme sinyali tarafından discriminator kapılı idi.

<ol>
	<li>Levick, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Another+tungsten+microelectrode.">Another tungsten microelectrode.</a> Med Biol Eng. 10 (4), 510-515 (1972).</li><li>Paxinos, G., Watson, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The rat brain in stereotaxic coordinates. , (1998).</li><li>Freeman, D. K., Heine, W. F., Passaglia, C. 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+maintained+discharge+of+rat+retinal+ganglion+cells.">The maintained discharge of rat retinal ganglion cells.</a> Vis Neurosci. 25 (4), 535-548 (2008).</li><li>Brainard, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+psychophysics+toolbox.">The psychophysics toolbox.</a> Spat Vis. 10, 433-436 (1997).</li></ol>

Tüm deneysel prosedürleri Boston Üniversitesi Kurumsal Hayvan Bakım ve Kullanım Kurulu tarafından kabul edildi.

Fiber optik kayıtlar sağlam bir göz gerektiren retina bilgi kodlama ve iletimi ile ilgili deneysel sorulara yanıt için cazip bir yaklaşım. Ayrıca, optik kiazma ya da yolu geçti ve çizgisiz optik sinir liflerinin aktivitesi tek bir elektrot penetrasyon ile kaydedilebilir elektrot yerleştirilmiş ise her iki gözü sinyalizasyon özellikleri hemen hemen aynı fizyolojik durumu incelenmelidir. Fiber optik kayıtları ortak vizyon araştırma, belki de kendi küçük boyutu sayesinde kemirgenler gibi diğer popü...

single-unit in vivo recordings from the optic chiasm of rat

Görsel dünya hakkında bilgiler, retina ganglion hücrelerinin aksonları optik sinir aksiyon potansiyelleri dizileri beyne iletilir.<em&gt; In vivo</em&gt; Çeşitli hayvan modellerinde ganglion hücre başak trenler kayıtları ne kadar erken görsel sistem süreçleri hakkında bilinen birçok şey anlattı ve görsel bilgiyi kodlar. Ancak, bu tür kayıtlar, muhtemelen küçük çaplı aksonlar tarafından ateş ani tespit zorluk nedeniyle en sık görülen hayvan modellerinde biri, sıçan, nadir olmuştur. Fareler üzerinde yapılan birçok retina hastalıkları modelleri, göz içi ya da göz bozmadan ganglion hücrelerinin fonksiyonel özellikleri tanımlamak için ihtiyaç motive<em&gt; In vitro</em&gt; Kayıtları. Burada, anestezi sıçan optik kiazma kayıt ganglion hücre başak trenler için bir yöntem ortaya koymaktadır. Biz ilk sıçan tek ganglion hücre aksonları elektriksel aktivite pick up-cam-tungsten elektrotlar imal nasıl göstermektedir. Elektrotlar denedim tüm ticari olanları çok daha üstündür. Bundan sonra bizim için özel tasarlanmış stereotaksik sistem göstermek<em&gt; In vivo</em&gt; Görsel nörofizyoloji deneyler ve hayvan hazırlanması ve optik kiazma güvenilir ve istikrarlı bir elektrot yerleştirme için prosedürler.

Watch this Scientific Journal Video about Single-unit In vivo Recordings from the Optic Chiasm of Rat at JoVE.com

Single-unit In vivo Recordings from the Optic Chiasm of Rat

Göz retina ganglion hücrelerinin aksiyon potansiyellerinin beyin dizileri ile görsel bilgi iletir. Burada, tek ganglion hücrelerinin aksiyon potansiyelleri kayıt nasıl göstermek<em&gt; In vivo</em&gt; Anestezi uygulanmış sıçanlarda.

Tek birim In vivo</emSıçan, optik kiazma> Kayıtlar

Information about the visual world is transmitted to the brain in sequences of action potentials in retinal ganglion cell axons that make up the optic ...

single-unit-in-vivo-recordings-from-the-optic-chiasm-of-rat

Research

JoVE Journal

Neuroscience

Single-unit In vivo Recordings from the Optic Chiasm of Rat

11.6K Görüntüleme.  Boston University. Göz retina ganglion hücrelerinin aksiyon potansiyellerinin beyin dizileri ile görsel bilgi iletir. Burada, tek ganglion hücrelerinin aksiyon potansiyelleri kayıt nasıl göstermek In vivo Anestezi uygulanmış sıçanlarda.

Video: Single-unit In vivo Recordings from the Optic Chiasm of Rat

Electrophysiological Recordings from the Giant Fiber Pathway of D. melanogaster

When startled adult D. melanogaster react by jumping into the air and flying away. In many invertebrate species, including D. melanogaster, the "escape" (or "startle") response during the adult stage is mediated by the multi-component neuronal circuit called the Giant Fiber System (GFS). The comparative large size of the neurons, their distinctive morphology and simple connectivity make the GFS an attractive model system for studying neuronal circuitry. The GFS pathway is composed of two bilaterally symmetrical Giant Fiber (GF) interneurons whose axons descend from the brain along the midline into the thoracic ganglion via the cervical connective. In the mesothoracic neuromere (T2) of the ventral ganglia the GFs form electro-chemical synapses with 1) the large medial dendrite of the ipsilateral motorneuron (TTMn) which drives the tergotrochanteral muscle (TTM), the main extensor for the mesothoracic femur/leg, and 2) the contralateral peripherally synapsing interneuron (PSI) which in turn forms chemical (cholinergic) synapses with the motorneurons (DLMns) of the dorsal longitudinal muscles (DLMs), the wing depressors. The neuronal pathway(s) to the dorsovental muscles (DVMs), the wing elevators, has not yet been worked out (the DLMs and DVMs are known jointly as indirect flight muscles - they are not attached directly to the wings, but rather move the wings indirectly by distorting the nearby thoracic cuticle) (King and Wyman, 1980; Allen et al., 2006). The di-synaptic activation of the DLMs (via PSI) causes a small but important delay in the timing of the contraction of these muscles relative to the monosynaptic activation of TTM (~0.5 ms) allowing the TTMs to first extend the femur and propel the fly off the ground. The TTMs simultaneously stretch-activate the DLMs which in turn mutually stretch-activate the DVMs for the duration of the flight. The GF pathway can be activated either indirectly by applying a sensory (e.g."air-puff" or "lights-off") stimulus, or directly by a supra-threshold electrical stimulus to the brain (described here). In both cases, an action potential reaches the TTMs and DLMs solely via the GFs, PSIs, and TTM/DLM motoneurons, although the TTMns and DLMns do have other, as yet unidentified, sensory inputs. Measuring "latency response" (the time between the stimulation and muscle depolarization) and the "following to high frequency stimulation" (the number of successful responses to a certain number of high frequency stimuli) provides a way to reproducibly and quantitatively assess the functional status of the GFS components, including both central synapses (GF-TTMn, GF-PSI, PSI-DLMn) and the chemical (glutamatergic) neuromuscular junctions (TTMn-TTM and DLMn-DLM). It has been used to identify genes involved in central synapse formation and to assess CNS function.

Electrophysiological Recordings from the Giant Fiber Pathway of D. melanogaster

The Giant Fiber System is a simple neuronal circuit of adult Drosophila melanogaster containing the largest neurons in the fly. We describe the protocol for monitoring synaptic transmission through this pathway by recording post synaptic potentials in dorsal longitudinal (DLM) and tergotrochanteral (TTM) muscles following direct stimulation of the Giant Fiber interneurons.

Dev Fiber Pathway Elektrofizyolojik Kayıtlar D. melanogaster</em

When startled adult D. melanogaster react by jumping into the air and flying away. In many invertebrate species, including D. melanogaster, the "escape" ...

Nörobilim

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from individual neurons are critical for understanding how neural circuits function under natural conditions. Traditionally, these recordings have been performed 'blind', meaning the identity of the recorded cell is unknown at the start of the recording. Cellular identity can be subsequently determined via intracellular1, juxtacellular2 or loose-patch3 iontophoresis of dye, but these recordings cannot be pre-targeted to specific neurons in regions with functionally heterogeneous cell types. Fluorescent proteins can be expressed in a cell-type specific manner permitting visually-guided single-cell electrophysiology4-6. However, there are many model systems for which these genetic tools are not available. Even in genetically accessible model systems, the desired promoter may be unknown or genetically homogenous neurons may have varying projection patterns. Similarly, viral vectors have been used to label specific subgroups of projection neurons7, but use of this method is limited by toxicity and lack of trans-synaptic specificity. Thus, additional techniques that offer specific pre-visualization to record from identified single neurons in vivo are needed. Pre-visualization of the target neuron is particularly useful for challenging recording conditions, for which classical single-cell recordings are often prohibitively difficult8-11. The novel technique described in this paper uses retrograde transport of a fluorescent dye applied using tungsten needles to rapidly and selectively label a specific subset of cells within a particular brain region based on their unique axonal projections, thereby providing a visual cue to obtain targeted electrophysiological recordings from identified neurons in an intact circuit within a vertebrate CNS.
The most significant novel advancement of our method is the use of fluorescent labeling to target specific cell types in a non-genetically accessible model system. Weakly electric fish are an excellent model system for studying neural circuits in awake, behaving animals12. We utilized this technique to study sensory processing by "small cells" in the anterior exterolateral nucleus (ELa) of weakly electric mormyrid fish. "Small cells" are hypothesized to be time comparator neurons important for detecting submillisecond differences in the arrival times of presynaptic spikes13. However, anatomical features such as dense myelin, engulfing synapses, and small cell bodies have made it extremely difficult to record from these cells using traditional methods11, 14. Here we demonstrate that our novel method selectively labels these cells in 28% of preparations, allowing for reliable, robust recordings and characterization of responses to electrosensory stimulation.

Retrograde Fluorescent Labeling Allows for Targeted Extracellular Single-unit Recording from Identified Neurons In vivo

Retrograde transport of fluorescent dye labels a sub-population of neurons based on anatomical projection. Labeled axons can be visually targeted in vivo, permitting extracellular recording from identified axons. This technique facilitates recording when neurons cannot be labeled through genetic manipulation or are difficult to isolate using 'blind' in vivo approaches.

Retrograd Floresan Etiketleme Belirlenen Nöronlar gelen Hedefli Hücre dışı Tek ünitesi Kayıt izin verir<em&gt; In vivo</em

The overall goal of this method is to record single-unit responses from an identified population of neurons. In vivo electrophysiological recordings from ...

A Procedure for Implanting Organized Arrays of Microwires for Single-unit Recordings in Awake, Behaving Animals

In vivo electrophysiological recordings in the awake, behaving animal provide a powerful method for understanding neural signaling at the single-cell level. The technique allows experimenters to examine temporally and regionally specific firing patterns in order to correlate recorded action potentials with ongoing behavior. Moreover, single-unit recordings can be combined with a plethora of other techniques in order to produce comprehensive explanations of neural function. In this article, we describe the anesthesia and preparation for microwire implantation. Subsequently, we enumerate the necessary equipment and surgical steps to accurately insert a microwire array into a target structure. Lastly, we briefly describe the equipment used to record from each individual electrode in the array. The fixed microwire arrays described are well-suited for chronic implantation and allow for longitudinal recordings of neural data in almost any behavioral preparation. We discuss tracing electrode tracks to triangulate microwire positions as well as ways to combine microwire implantation with immunohistochemical techniques in order to increase the anatomical specificity of recorded results.

Implanting organized arrays of microwires for use in single-unit electrophysiological recordings presents a number of technical challenges.&#160;Methods for performing this technique and the equipment necessary are described.&#160;Also, the beneficial use of organized microwire arrays to record from distinct neural subregions with high spatial selectivity is discussed.

Hayvanlar davranmak, Awake Tek-birim Recordings Microwires Organize Dizileri implantasyon için Usulü

In vivo electrophysiological recordings in the awake, behaving animal provide a powerful method for understanding neural signaling at the single-cell ...

A Guide to In vivo Single-unit Recording from Optogenetically Identified Cortical Inhibitory Interneurons

A major challenge in neurophysiology has been to characterize the response properties and function of the numerous inhibitory cell types in the cerebral cortex. We here share our strategy for obtaining stable, well-isolated single-unit recordings from identified inhibitory interneurons in the anesthetized mouse cortex using a method developed by Lima and colleagues1. Recordings are performed in mice expressing Channelrhodopsin-2 (ChR2) in specific neuronal subpopulations. Members of the population are identified by their response to a brief flash of blue light. This technique &#8211; termed &#8220;PINP&#8221;, or Photostimulation-assisted Identification of Neuronal Populations &#8211; can be implemented with standard extracellular recording equipment. It can serve as an inexpensive and accessible alternative to calcium imaging or visually-guided patching, for the purpose of targeting extracellular recordings to genetically-identified cells. Here we provide a set of guidelines for optimizing the method in everyday practice. We refined our strategy specifically for targeting parvalbumin-positive (PV+) cells, but have found that it works for other interneuron types as well, such as somatostatin-expressing (SOM+) and calretinin-expressing (CR+) interneurons.

A Guide to In vivo Single-unit Recording from Optogenetically Identified Cortical Inhibitory Interneurons

Here we describe our strategy for obtaining stable, well-isolated single-unit recordings from identified inhibitory interneurons in the anesthetized mouse cortex. Neurons expressing ChR2 are identified by their response to blue light. The method uses standard extracellular recording equipment, and serves as an inexpensive alternative to calcium imaging or visually-guided patching.

A Guide<em&gt; In vivo</emOptogenetically Belirlenen Kortikal inhibitör dan&gt; Tek birim Kayıt

A major challenge in neurophysiology has been to characterize the response properties and function of the numerous inhibitory cell types in the cerebral ...

Minimally-invasive Technique for Injection into Rat Optic Nerve

The rat optic nerve is a useful model for stem cell regeneration research. Direct injection into the rat optic nerve allows delivery into the central nervous system in a minimally-invasive surgery without bone removal. This technique describes an approach to visualization and direct injection of the optic nerve following minor fascial dissection from the orbital ridge, using a conjunctival traction suture to gently pull the eye down and out. Representative examples of an injected optic nerve show successful injection of dyed beads.

Direct injection into the rat optic nerve is useful for regenerative research. We demonstrate a minimally-invasive technique for direct injection into a rat optic nerve that does not involve opening the skull. Using this method, surgical complications are minimized and recovery is more rapid.

Sıçan Optik Sinir içine Enjeksiyon için minimal invaziv Tekniği

The rat optic nerve is a useful model for stem cell regeneration research. Direct injection into the rat optic nerve allows delivery into the central ...

Visual Evoked Potential Recording in a Rat Model of Experimental Optic Nerve Demyelination

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to monitor the disease course in the follow-up period. Changes in the VEP parameters closely correlate with pathological damage in the optic nerve. This protocol provides a detailed description about the rodent model of optic nerve microinjection, in which a partial demyelination lesion is produced in the optic nerve. VEP recording techniques are also discussed. Using skull implanted electrodes, we are able to acquire reproducible intra-session and between-session VEP traces. VEPs can be recorded on individual animals over a period of time to assess the functional changes in the optic nerve longitudinally. The optic nerve demyelination model, in conjunction with the VEP recording protocol, provides a tool to investigate the disease processes associated with demyelination and remyelination, and can potentially be employed to evaluate the effects of new remyelinating drugs or neuroprotective therapies.

Focal demyelination is induced in the optic nerve using lysolecithin microinjection. Visual evoked potentials are recorded via skull electrodes implanted over the visual cortex to examine the signal conduction along the visual pathway in vivo. This protocol details the surgical procedures underlying electrode implantation and optic nerve microinjection.

Deneysel Optik Sinir demyelinizasyon bir Rat Modelinde Görsel Uyarılmış Potansiyel Kayıt

The visual evoked potential (VEP) recording is widely used in clinical practice to assess the severity of optic neuritis in its acute phase, and to ...

Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings

Intracellular recording is a powerful technique used to determine how a single cell may respond to a given stimulus. In vision research, intracellular recording has historically been a common technique used to study sensitivities of individual photoreceptor cells to different light stimuli that is still being used today. However, there remains a dearth of detailed methodology in the literature for researchers wishing to replicate intracellular recording experiments in the eye. Here we present the insect as a model for examining eye physiology more generally. Insect photoreceptor cells are located near the surface of the eye and are therefore easy to reach, and many of the mechanisms involved in vision are conserved across animal phyla. We describe the basic procedure for in vivo intracellular recording of photoreceptor cells in the eye of a butterfly, with the goal of making this technique more accessible to researchers with little prior experience in electrophysiology. We introduce the basic equipment needed, how to prepare a live butterfly for recording, how to insert a glass microelectrode into a single cell, and finally the recording procedure itself. We also explain the basic analysis of raw response data for determining spectral sensitivity of individual cell types. Although our protocol focuses on determining spectral sensitivity, other stimuli (e.g., polarized light) and variations of the method are applicable to this setup.

Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings

The electrophysiological technique of intracellular recording is demonstrated and used to determine spectral sensitivities of single photoreceptor cells in the compound eye of a butterfly.

bir Böcek Modeli fotoreseptör hücre spektral Duyarlılık Belirlenmesi<em&gt; İn Vivo</em&gt; Hücre içi Kayıtlar

Intracellular recording is a powerful technique used to determine how a single cell may respond to a given stimulus. In vision research, intracellular ...

Acute In Vivo Electrophysiological Recordings of Local Field Potentials and Multi-unit Activity from the Hyperdirect Pathway in Anesthetized Rats

Converging evidence shows that many neuropsychiatric diseases should be understood as disorders of large-scale neuronal networks. To better understand the pathophysiological basis of these diseases, it is necessary to precisely characterize in which way the processing of information is disturbed between the different neuronal parts of the circuit. Using extracellular in vivo electrophysiological recordings, it is possible to accurately delineate neuronal activity within a neuronal network. The application of this method has several advantages over alternative techniques, e.g., functional magnetic resonance imaging and calcium imaging, as it allows a unique temporal and spatial resolution and does not rely on genetically engineered organisms. However, the use of extracellular in vivo recordings is limited since it is an invasive technique that cannot be universally applied. In this article, a simple and easy to use method is presented with which it is possible to simultaneously record extracellular potentials such as local field potentials and multiunit activity at multiple sites of a network. It is detailed how a precise targeting of subcortical nuclei can be achieved using a combination of stereotactic surgery and online analysis of multi-unit recordings. Thus, it is demonstrated, how a complete network such as the hyperdirect cortico-basal ganglia loop can be studied in anesthetized animals in vivo.

Acute In Vivo Electrophysiological Recordings of Local Field Potentials and Multi-unit Activity from the Hyperdirect Pathway in Anesthetized Rats

In this study, the methodology is presented on how to perform multi-site in vivo electrophysiological recordings from the hyperdirect pathway under urethane anesthesia.

Akut<emIn vivo</em&gt; Anestezi Uygulanan Sıçanlarda Hiperdirect Pathway&#39;den Lokal Alan Potansiyellerinin Elektrofizyolojik Kayıtları ve Çoklu Ünite Aktivitesi

Converging evidence shows that many neuropsychiatric diseases should be understood as disorders of large-scale neuronal networks. To better understand the ...

Simultaneous Recordings of Cortical Local Field Potentials, Electrocardiogram, Electromyogram, and Breathing Rhythm from a Freely Moving Rat

Monitoring the physiological dynamics of the brain and peripheral tissues is necessary for addressing a number of questions about how the brain controls body functions and internal organ rhythms when animals are exposed to emotional challenges and changes in their living environments. In general experiments, signals from different organs, such as the brain and the heart, are recorded by independent recording systems that require multiple recording devices and different procedures for processing the data files. This study describes a new method that can simultaneously monitor electrical biosignals, including tens of local field potentials in multiple brain regions, electrocardiograms that represent the cardiac rhythm, electromyograms that represent awake/sleep-related muscle contraction, and breathing signals, in a freely moving rat. The recording configuration of this method is based on a conventional micro-drive array for cortical local field potential recordings in which tens of electrodes are accommodated, and the signals obtained from these electrodes are integrated into a single electrical board mounted on the animal's head. Here, this recording system was improved so that signals from the peripheral organs are also transferred to an electrical interface board. In a single surgery, electrodes are first separately implanted into the appropriate body parts and the target brain areas. The open ends of all of these electrodes are then soldered to individual channels of the electrical board above the animal's head so that all of the signals can be integrated into the single electrical board. Connecting this board to a recording device allows for the collection of all of the signals into a single device, which reduces experimental costs and simplifies data processing, because all data can be handled in the same data file. This technique will aid the understanding of the neurophysiological correlates of the associations between central and peripheral organs.

This study introduces a method for the simultaneous recording of local field potentials in the brain, electrocardiograms, electromyograms, and breathing signals of a freely moving rat. This technique, which reduces experimental costs and simplifies data analysis, will contribute to the understanding of the interactions between the brain and peripheral organs.

Kortikal yerel alan potansiyelleri, Elektrokardiyogram, Electromyogram ve ritim serbestçe hareket bir sıçan gelen nefes eşzamanlı kayıt

Monitoring the physiological dynamics of the brain and peripheral tissues is necessary for addressing a number of questions about how the brain controls ...

Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined curved surfaces, and images of real-world objects (with and without disparity) in a similar manner as described in the ventral visual stream. In addition, parieto-frontal areas are believed to convert visual object information into appropriate motor outputs, such as the pre-shaping of the hand during grasping. To better characterize object selectivity in the cortical network involved in visuomotor transformations, we provide a battery of tests intended to analyze the visual object selectivity of neurons in parieto-frontal regions.

A detailed protocol to analyze object selectivity of parieto-frontal neurons involved in visuomotor transformations is presented.

Tek-unit kayıtları kullanarak nesne temsilcilikleri makak Dorsal Visual akışı soruşturma

Previous studies have shown that neurons in parieto-frontal areas of the macaque brain can be highly selective for real-world objects, disparity-defined ...

Tek birim In vivo Kayıtlar