Supported by grants from CIHR (MOP231122) and NSERC (RGPIN-2014-06503). We would like to thank Genevi&#232;ve Cyr for her help preparing experiments and supervising laboratory work. MAL received a scholarship from The Natural Sciences and Engineering Research Council of Canada (NSERC).

NOT: Tüm prosedürler Hayvanları Koruma ve Université de Montréal Etik inceleme kurulu Kanada Konseyi direktifleri doğrultusunda yapıldı. Kayıt enjeksiyon Pipet 1. Meclisi <ol><li> Bir pipet çektirmenin kullanarak yaklaşık 7 cm uzunluğunda bir cam kapiller (1 mm dış çapı) çekin. </li><li> Kılcal ucu kırın ve bir ışık mikroskobu altında diyafram kontrol edin. Iç çapı 40 mikron 30 mikron arasında olduğunu onaylayın. </li><li> Cam pipet olmayan konik ucundan çıkıntılı yaklaşık 1 cm cam kapiller içine 7 cm uzunluğunda gümüş tel yerleştirin. </li><li> Cam kapiller dikey olarak aşırı filament bükün. </li><li> Bir 30 G hipodermik iğnenin mil üzerinde esnek plastik bir yapışkan damlacık uygulanır. </li><li> Şekil 1 &#39;de sunulan şemadaki gibi cam pipet bir 30 G hipodermik iğne takın </stro&gt; ng. </li><li> Cam pipet ve hipodermik iğne arasındaki birleşme gelen uygun bir sızdırmazlık sağlamak için yapıştırıcı bir ikinci kaplama ekleyin. </li><li> Ucu tutkal uygun kür sağlamak için yaklaşık 12 saat boyunca yukarı bakacak şekilde kurumaya pipet bırakın. bitmiş sonucu, Şekil 2&#39;de gösterilmiştir. </li></ol> Not: Bu yordam, akut deneyler ve pipet sterilizasyonu yapılır gerekli değildir. 2. Hayvan hazırlanması <ol><li> Bir anestezi kutusuna sıçan yerleştirin. </li><li> 5 ila 10 dakika süreyle% 4 izofluran kullanarak anestezi neden olur. </li><li> 37 ° C&#39;lik bir vücut ısısını korumak için ısıtma yastığı ve rektal prob ile bir stereotaksik tablo hayvan yerleştirin. % 2 izofluran ile anestezi korumak için burun konisi kullanın. Kulak çubukları ve dişlerin tutucu kullanarak sıçan başını sabitleyin. </li><li> Atropin öğrenci genişlemesi yardımcı olmak için damla% 1 dahil oftalmik merhem ya da göz damlaları, uygulayın. Kuruluğunu önlemek için, damla yağlama uygulamakYaklaşık her 30 dk s. </li><li> Kafa Tıraş ve% 10 povidon-iyot ile temizleyiniz. </li><li> Lokal anestezi için, cildi yukarı kaldırma ve iğne ucu takarak 2-3 yerlerde kafa derisi altında% 2 lidokain 0.5 ml enjekte edilir. </li><li> Bir ayak tutam performans ve hareket eksikliği gözlemleyerek anestezi yeterli düzeyde onaylayın. Buna ek olarak, normal değerler (300-400 atım / dak) içinde olduğundan emin olmak için kalp hızı izleme. </li><li> Koronal ve sagital sütür hem duyurmak için bir 10. neşter bıçağı ile medyan boyunca düz bir çizgi derisini İnsizyon. </li><li> Cerrahi spatula ile kafatası kapsayan doku bir kenara iterek Lambda ve Bregma noktaları açığa vurmak. </li><li> Bregma ve Lambda pozisyonları aynı düzlemde olacak şekilde kafatası Seviye. </li><li> Referans noktasını ayarlamak için, sağ bregmadan yukarıda ayarlamak için bir monte edilmiş cam tüp ile bir stereotaksik cihaz kullanın. Bu &quot;sıfır&quot; için ön-arka ve med olacakial yanal ölçümler koordine eder. </li><li> Stereotaksik gerekli koordinatları montaj hareket ettirerek ilgi noktasını ayarlayın stereotaksik koordinatları not ve kraniyotomi yapılacaktır nerede işaretleri hedef alan etrafında bir kare çizin. </li><li> Yavaş yavaş kemik malzemeyi çıkarmak için baskı olmadan yavaş yavaş belirgin meydanda boyunca sterilize matkapla bir cerrahi matkap kullanın. Bu korteks üzerindeki lezyonlar ısı üretmek ve neden olacağından, aynı bölgede çok uzun inebilecek dikkatli olun. </li><li> Kraniotomiye sınırlayan kemik yeterince ince eriştiğinde, dikkatlice korteks maruz cımbız ile kranial bölümü çıkarın. </li><li> Sıkça doku kuruma önlemek için yapay beyin omurilik sıvısı ile maruz korteksi sulamak. NOT: injectrode ucu nüfuz kadar sağlam olduğu Dura mater kaldırma sıçan üzerinde gereksiz olduğunu. </li></ol> 3. Doldurma ve Enjeksiyon Sistemi montajı <ol><li> DoldurmakMineral yağ ile aspirasyon ile 5-10 ul mikroenjektör. </li><li> % 0.5 Chicago Sky Blue (CSB) ile 300 uM γ-aminobutirik asit (GABA) ya da% 0.5 CSB 9% 2 lidokain çözeltisi içeren bir çözelti ile, sabit bir cam pipet ile deri altı iğne doldurun. Tuzlu su ile bütün çözümleri seyreltin. <ol><li> Bol bir madde olması halinde, normal bir şırınga kullanılarak girip hava kabarcıklarının oluşumunu önlemek için normal önlemler tekniklerini kullanır. </li><li> Daha pahalı maddeler durumunda, injectrode doldurmak için mineral yağ kullanımı ve kimyasal madde daha sonra aspirasyon ile sokulabilir. Mineral yağ ve su arasındaki yoğunluk farkı nispeten yüksek olduğu için, bu madde, sulu çözeltiler enjeksiyon için iyi bir adaydır. Not: bir boya iki sıvı arasındaki mesafeyi teyit etmek için ilave edilebilir. </li></ol></li><li> Enjeksiyon pipet doldurmak için, aspirasyonla çözeltisi ile 1 ml şırınga girip daha sonra yavaş yavaş solüsyon enjekteEnjeksiyon pipet içine. </li><li> Temiz bu alanları swabbing ve ayrıca şırınga ile yavaşça çözüm enjekte ederek kaçaklar gözlemleyerek Şekil 1&#39;de gösterilen bölgelerde sızıntı olup olmadığını dikkat ediniz. </li><li> 1 ml şırınga çıkarın. Bunu yaparken, vakum enjeksiyon pipet gelen çözüm kaldırmaz, böylece pistonu hafif bir basınç tutmak için emin olun. </li><li> Aspirasyon mineral yağ ile mikroenjektör doldurun ve dolu enjeksiyon pipet sıkıca takın, sonra dikkatlice gazlı bez ile bir araya injectrode herhangi bir aşırı çözüm silerek temizleyin. </li><li> Ucu cam pipet ucu şekillendirme küçük bir damla görmek için yeterli çok küçük bir hacim, enjekte edilerek tıkalı olmadığından emin olun. </li><li> Mikropompa sistemi üzerinde injectrode monte ve iyi sabit olduğundan emin olun. </li><li> Dikkatle hedef koordinatlarında injectrode ucunu yerleştirin ve korteks yüzeyine ucu indirin. </li><li> Yavaşça injectr düşürmekUygun anatomik koordinatları kullanarak hedef yapısına stereotaksik aparatı (bu durumda üstün colliculus) kullanarak gazel. </li><li> Doku kuruma önlemek için sıcak agar ile maruz korteksi örtün. </li></ol> 4. Enjeksiyon ve Tersinir İnaktivasyonu <ol><li> Enjeksiyonu başlatmak için 40 nl / dak ve basın Run 400 nl 800 enjekte mikroenjeksiyon pompasını ayarlayın. O başak oranı enjeksiyon sırasında azalma gösterecektir unutmayın. NOT: deney düzeneği, sinirsel aktivite GABA doğum bitiminden sonra bir saat içinde iyileşti. Herhangi bir kalibre mekanik cihaz enjeksiyonu yapmak amacıyla mikroenjeksiyon şırınga baskı uygulamak için kullanılabilir. </li><li> Elektrofizyolojik veriler kazanılmasından sonra, yerel Hayvan Etik Topluluğu tarafından onaylanmış bir yöntem kullanılarak euthanize. </li></ol>

<ol>
	<li>Martin, J. H., Ghez, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacological+inactivation+in+the+analysis+of+the+central+control+of+movement.">Pharmacological inactivation in the analysis of the central control of movement.</a> Journal Of Neuroscience Methods. 86 (2), 145-159 (1999).</li><li>Ponce, C. R., Hunter, J. N., Pack, C. C., Lomber, S. G., Born, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contributions+of+indirect+pathways+to+visual+response+properties+in+macaque+middle+temporal+area+MT.">Contributions of indirect pathways to visual response properties in macaque middle temporal area MT.</a> The Journal Of Neuroscience The Official Journal Of The Society For Neuroscience. 31 (10), 3894-3903 (2011).</li><li>Lomber, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+advantages+and+limitations+of+permanent+or+reversible+deactivation+techniques+in+the+assessment+of+neural+function.">The advantages and limitations of permanent or reversible deactivation techniques in the assessment of neural function.</a> Journal Of Neuroscience Methods. 86 (2), 109-117 (1999).</li><li>Malpeli, J., Schiller, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+of+reversible+inactivation+of+small+regions+of+brain+tissue.">A method of reversible inactivation of small regions of brain tissue.</a> Journal Of Neuroscience Methods. 1 (2), 143-151 (1979).</li><li>Lomber, S. 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(46), (2010).</li><li>Hup&#233;, J., Chouvet, G., Bullier, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+temporal+parameters+of+cortical+inactivation+by+GABA.">Spatial and temporal parameters of cortical inactivation by GABA.</a> Journal Of Neuroscience Methods. 86 (2), 129-143 (1999).</li><li>Casanova, C., McKinley, P., Molotchnikofff, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Responsiveness+of+Reorganized+Primary+Somatosensory+(SI)+Cortex+after+Local+Inactivation+of+Normal+SI+Cortex+in+Chronic+Spinal+Cats.">Responsiveness of Reorganized Primary Somatosensory (SI) Cortex after Local Inactivation of Normal SI Cortex in Chronic Spinal Cats.</a> Somatosensory &amp; Motor Research. 8 (1), 65-76 (1991).</li><li>Malpeli, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversible+inactivation+of+subcortical+sites+by+drug+injection.">Reversible inactivation of subcortical sites by drug injection.</a> Journal Of Neuroscience Methods. 86 (2), 119-128 (1999).</li><li>Minville, K., Casanova, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+frequency+processing+in+posteromedial+lateral+suprasylvian+cortex+does+not+depend+on+the+projections+from+the+striate-recipient+zone+of+the+cat&#8217;s+lateral+posterior-pulvinar+complex.">Spatial frequency processing in posteromedial lateral suprasylvian cortex does not depend on the projections from the striate-recipient zone of the cat&#8217;s lateral posterior-pulvinar complex.</a> Neuroscience. 84 (3), 699-711 (1998).</li><li>Diao, Y., Wang, Y., Xiao, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Representation+of+the+binocular+visual+field+in+the+superior+colliculus+of+the+albino+rat.">Representation of the binocular visual field in the superior colliculus of the albino rat.</a> Experimental Brain Research. 52 (1), 67-72 (1983).</li></ol>

We have nothing to disclose.

Önerilen protokol mevcut geri dönüşümlü etkisizleştirme yöntemleri kaynaklanan sorunları çözmek için tasarlanmıştır. Özellikle bu proje özellikle derin beyin yapılarında nöral aktiviteyi modüle maddelerin kimyasal microinjections için kullanılan yöntemleri rafine yönelik. Kurulum bu tür ortaya çıkan bir teknik zorluk, her iki sondalar enjeksiyon yerinde kesin kayıtları elde etmek amacıyla in vivo aynı kısıtlı alanda kolokalize edilmesi ihtiyacıdır. Bu sorun, aynı sitede Enj...

kortikal alan ve alt kortikal çekirdeklerin inaktivasyonu, çeşitli beyin yapıları 2-4 arasındaki fonksiyonel ilişkiler çalışmalarında önemlidir. Son literatür beyin yapılarının 2,5 rolünü incelemek için kayıp fonksiyon-kimyasal veya kriyojenik teknikleri istihdam vardır. Çevre doku 6,7 kollateral hasarı en aza indirerek ilaç microinjections ilgili olarak, ilaçların küçük miktarlar kontrollü bir hızda, bir beyin bölgesine uygulanabilir. Bu teknik, nöronal aktivitenin farklı farmakolojik hedeflerin etkisini incelemek için spesifik agonistleri, ters agonistleri veya antagonistleri sunmak için de kullanılabilir. Bu tür etkileri de araştırmacılar, farklı kortikal ve subkortikal yapılar arasındaki ilişkileri incelemek için izin uzak yerlerden nöronal yanıtları değişiklikleri ölçerek ele alınabilir. Burada, biz bo yeteneğine sahip bir cihazın montajını, injectrode, göstermekelektrofizyolojik sinyaller kayıt ve hedef konumda ilaçların küçük miktarlarda teslim inci. Biz sıçan üstün colliculus, GABA, nöronal aktivitenin ortak bir inhibitörü enjekte edilerek bu sistemin yeteneklerini göstermek. Bu bölge bize injectrode yerelleştirme onaylamak için görsel uyarılmış multiunit aktiviteyi kullanmak için izin görsel uyarı, duyarlıdır. inaktivasyon reversibilitesinin GABA enjeksiyonu bitimini izleyen, normal nöronal aktivitenin iyileşme ile değerlendirildi. enjeksiyon bölgesinden çok üniteli etkinliğini izlemek için yeteneği istenen farmakodinamik yanıtı elde etmek için gerekli enjeksiyon oranları ve hacimlerin ince ayar için izin verir. En küçük etkili miktarlar enjekte edilir çünkü Bu nedenle, bu tekniğin bir avantajı, Şekilde, mikro neden olduğu doku hasarının sınırlayıcı potansiyelidir. önerilen protokol tek bir donanım necessar üretilmesi için bir maliyet açısından verimli bir yöntem sağlarilaç verme ve yerel nöronal etkinliği kayıt istendiği deneyleri yürütmek için y.

<table border="0" cellpadding="0" cellspacing="0" width="981">
	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:280px;">Name of the reagent</td>
			<td style="width:209px;">Company</td>
			<td style="width:184px;">Catalogue number</td>
			<td style="width:308px;">Comments (optional)</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:280px;">Injection pump (UltraMicroPump III)</td>
			<td style="width:209px;">WPI</td>
			<td style="width:184px;">#UMP3</td>
			<td style="width:308px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:280px;">Injection console (Micro4 Controller)</td>
			<td style="width:209px;">WPI</td>
			<td style="width:184px;">#SYS-MICRO4</td>
			<td style="width:308px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:280px;">Hamilton syringe</td>
			<td style="width:209px;">Hamliton</td>
			<td style="width:184px;">(80301) 701LT 10 &#181;L SYR</td>
			<td style="width:308px;">Syringes between 5 and 10 &#956;L used</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:280px;">Gel cyanoacrylate adhesive</td>
			<td style="width:209px;">Krazy Glue</td>
			<td style="width:184px;">KG86648R</td>
			<td style="width:308px;">The gel form is easier to apply on the shaft of the 30G hypodermic needle</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:280px;">Glass pipettes</td>
			<td style="width:209px;">WPI</td>
			<td style="width:184px;">#TW100F-4</td>
			<td style="width:308px;">Thin wall, 1mm OD, 0.75mm ID with filament pipettes used</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:280px;">720 Needle Pipette Puller</td>
			<td style="width:209px;">Kopf</td>
			<td style="width:184px;">720</td>
			<td style="width:308px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:280px;">Silver wire</td>
			<td style="width:209px;">A-M Systems, Inc.</td>
			<td style="width:184px;">782500</td>
			<td style="width:308px;">Bare 0.010&#8221;</td>
		</tr>
	</tbody>
</table>

simultaneous electrophysiological recording and micro-injections of inhibitory agents in the rodent brain

Burada ticari olarak erişilebilir ve uygun fiyatlı parçalar kullanarak tek kullanımlık &quot;injectrode&quot; yapımı için bir yöntem açıklanmaktadır. Bir tarama sisteminin etkilenen nöronal popülasyonundan elektrofizyolojik sinyalleri kayıt sırasında bir ilacın enjeksiyonu sağlar geliştirildi. Bu yöntem, ticari çözümler için basit ve ekonomik bir alternatif sağlar. Bir cam pipet bir hipodermik iğne ve gümüş filament ile birleştirilmesi suretiyle modifiye edildi. injectrode ilaç iletimi için ticari bir mikroenjektör pompasına bağlanmıştır. Bu ilaç dağıtım sitesinden kaynaklanan çoklu ünite dışı sinyalleri aracılığıyla gerçek zamanlı farmakodinamikler geri bildirim sağlayan teknikle sonuçlanır. Kavramının bir kanıtı olarak, eş zamanlı olarak injectrode yoluyla ilaçların teslimi ile, sıçanlarda ışık yanıp söner tarafından ortaya üstün colliculus gelen nöronal aktivitenin kaydetti. injectrode kayıt kapasitesi inj fonksiyonel karakterizasyonu izin veririlaç dağıtım lokalizasyonu üzerinde hassas kontrol lehine ection sitesi. Injectrode yüklü kimyasal madde seçimi anatomik deneyler için işaretleyiciler izleme dahil olmak üzere, geniş bir şekilde, bu yöntemin uygulanması, aynı zamanda, buradan çok gösterilmiştir ötesine uzanır.

injectrode inşaat tel bükülmüş bir kısmı ile bir cam pipet (D) içine beslenir ve açıklıktan dışarı doğru çıkıntı yapan, Şekil 1 bir gümüş tel (C) &#39;de gösterilmiştir. A 30 G iğne (B) bağlı ve yapıştırıcı ile cam pipet açılmasına kapatılır. Pipet püskürtme maddesi ile doldurulduktan sonra, cam mikro şırınga (A), bir iğne takılır. Mikro şırınga iğnesi (E) ve nerede gümüş tel cam pipet (F) çıkıntı bağlanır iyi bir mühür var olması önemlidir....

Watch this Scientific Journal Video about Simultaneous Electrophysiological Recording and Micro-injections of Inhibitory Agents in the Rodent Brain at JoVE.com

Simultaneous Electrophysiological Recording and Micro-injections of Inhibitory Agents in the Rodent Brain

Here, we craft a glass pipette with dual functions: inhibition of deep brain structures by microinjections of drugs and real-time monitoring of their effects through simultaneous electrophysiological recordings.

Eşzamanlı Elektrofizyolojik Kayıt ve kemirgen Beyindeki inhibitör Ajanların Mikro-enjeksiyon

Here we describe a method for the construction of a single-use &#8220;injectrode&#8221; using commercially accessible and affordable parts. A probing ...

simultaneous-electrophysiological-recording-micro-injections

Research

JoVE Journal

Neuroscience

8.0K Görüntüleme.  Université de Montréal. Here, we craft a glass pipette with dual functions: inhibition of deep brain structures by microinjections of drugs and real-time monitoring of their effects through simultaneous electrophysiological recordings.

Video: Simultaneous Electrophysiological Recording and Micro-injections of Inhibitory Agents in the Rodent Brain

Simultaneous fMRI and Electrophysiology in the Rodent Brain

To examine the neural basis of the blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) signal, we have developed a rodent model in which functional MRI data and in vivo intracortical recording can be performed simultaneously. The combination of MRI and electrical recording is technically challenging because the electrodes used for recording distort the MRI images and the MRI acquisition induces noise in the electrical recording. To minimize the mutual interference of the two modalities, glass microelectrodes were used rather than metal and a noise removal algorithm was implemented for the electrophysiology data. In our studies, two microelectrodes were separately implanted in bilateral primary somatosensory cortices (SI) of the rat and fixed in place. One coronal slice covering the electrode tips was selected for functional MRI. Electrode shafts and fixation positions were not included in the image slice to avoid imaging artifacts. The removed scalp was replaced with toothpaste to reduce susceptibility mismatch and prevent Gibbs ringing artifacts in the images. The artifact structure induced in the electrical recordings by the rapidly-switching magnetic fields during image acquisition was characterized by averaging all cycles of scans for each run. The noise structure during imaging was then subtracted from original recordings. The denoised time courses were then used for further analysis in combination with the fMRI data. As an example, the simultaneous acquisition was used to determine the relationship between spontaneous fMRI BOLD signals and band-limited intracortical electrical activity. Simultaneous fMRI and electrophysiological recording in the rodent will provide a platform for many exciting applications in neuroscience in addition to elucidating the relationship between the fMRI BOLD signal and neuronal activity.

We have developed a method for simultaneous functional magnetic resonance imaging and electrophysiological recording in the rodent brain, providing a platform for the investigation of the relationship between neural activity and the blood oxygenation level dependent (BOLD) MRI signal.

Kemirgen Beyin aynı anda fMRI ve Elektrofizyoloji

To examine the neural basis of the blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) signal, we have developed a rodent model in ...

Nörobilim

Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze

Headstage preamplifiers and source followers are commonly used to study neural activity in behavioral neurophysiology experiments. Available commercial products are often expensive, not easily customized, and not submersible. Here we describe a method to design and build a customized, integrated circuit headstage for simultaneous 4-channel neural recording and 2-channel simulation in awake, behaving animals. The headstage is designed using a free, commercially available CAD-type design package, and can be modified easily to accommodate different scales (e.g. to add channels). A customized printed circuit board is built using surface mount resistors, capacitors and operational amplifiers to construct the unity gain source follower circuit. The headstage is made water-proof with a combination of epoxy, parafilm and a synthetic rubber putty. We have successfully used this device to record local field potentials and stimulate different brain regions simultaneously via independent channels in rats swimming in a water maze. The total cost is &lt; $30/unit and can be manufactured readily.

We present a low-cost method to design and construct a light headstage pre-amplifier system with simultaneous neural recording and stimulation capability. This device can be waterproofed for use in swimming animals.

Eşzamanlı Sinir Uyarım ve Su Maze Kayıt için Tasarım ve İnşaat Maliyet Etkin headstage

Headstage preamplifiers and source followers are commonly used to study neural activity in behavioral neurophysiology experiments. Available commercial ...

Forebrain Electrophysiological Recording in Larval Zebrafish

Epilepsy affects nearly 3 million people in the United States and up to 50 million people worldwide. Defined as the occurrence of spontaneous unprovoked seizures, epilepsy can be acquired as a result of an insult to the brain or a genetic mutation. Efforts to model seizures in animals have primarily utilized acquired insults (convulsant drugs, stimulation or brain injury) and genetic manipulations (antisense knockdown, homologous recombination or transgenesis) in rodents. Zebrafish are a vertebrate model system1-3 that could provide a valuable alternative to rodent-based epilepsy research. Zebrafish are used extensively in the study of vertebrate genetics or development, exhibit a high degree of genetic similarity to mammals and express homologs for ~85% of known human single-gene epilepsy mutations. Because of their small size (4-6 mm in length), zebrafish larvae can be maintained in fluid volumes as low as 100 &mu;l during early development and arrayed in multi-well plates. Reagents can be added directly to the solution in which embryos develop, simplifying drug administration and enabling rapid in vivo screening of test compounds4. Synthetic oligonucleotides (morpholinos), mutagenesis, zinc finger nuclease and transgenic approaches can be used to rapidly generate gene knockdown or mutation in zebrafish5-7. These properties afford zebrafish studies an unprecedented statistical power analysis advantage over rodents in the study of neurological disorders such as epilepsy. Because the "gold standard" for epilepsy research is to monitor and analyze the abnormal electrical discharges that originate in a central brain structure (i.e., seizures), a method to efficiently record brain activity in larval zebrafish is described here. This method is an adaptation of conventional extracellular recording techniques and allows for stable long-term monitoring of brain activity in intact zebrafish larvae. Sample recordings are shown for acute seizures induced by bath application of convulsant drugs and spontaneous seizures recorded in a genetically modified fish.

A simple method to record extracellular field potentials in the larval zebrafish forebrain is described. The method provides a robust in vivo read-out of seizure-like activity. This technique can be used with genetically modified zebrafish larvae carrying epilepsy-related genes or seizures evoked by administration of convulsant drugs.

Larva Zebra balığı olarak önbeyin Elektrofizyolojik Kaydı

Epilepsy affects nearly 3 million people in the United States and up to 50 million people worldwide. Defined as the occurrence of spontaneous unprovoked ...

Simultaneous Pre- and Post-synaptic Electrophysiological Recording from Xenopus Nerve-muscle Co-cultures

Much information about the coupling of presynaptic ionic currents with the release of neurotransmitter has been obtained from invertebrate preparations, most notably the squid giant synapse1. However, except for the preparation described here, few vertebrate preparations exist in which it is possible to make simultaneous measurements of neurotransmitter release and presynaptic ionic currents. Embryonic Xenopus motoneurons and muscle cells can be grown together in simple culture medium at room temperature; they will form functional synapses within twelve to twenty-four hours, and can be used to study nerve and muscle cell development and synaptic interactions for several days (until overgrowth occurs). Some advantages of these co-cultures over other vertebrate preparations include the simplicity of preparation, the ability to maintain the cultures and work at room temperature, and the ready accessibility of the synapses formed2-4. The preparation has been used widely to study the biophysical properties of presynaptic ion channels and the regulation of transmitter release5-8. In addition, the preparation has lent itself to other uses including the study of neurite outgrowth and synaptogenesis9-12, molecular mechanisms of neurotransmitter release13-15, the role of diffusible messengers in neuromodulation16,17, and in vitro synaptic plasticity18-19.

Simultaneous Pre- and Post-synaptic Electrophysiological Recording from Xenopus Nerve-muscle Co-cultures

This video demonstrates the procedures used to grow primary cultures of embryonic Xenopus nerve and muscle cells and the usefulness of this preparation for making simultaneous pre- and post-synaptic patch clamp recordings.

Eşzamanlı Öncesi ve Sonrası-sinaptik Elektrofizyolojik Recording<em&gt; Xenopus</em&gt; Sinir-kas Co-kültürlerin

Much information about the coupling of  presynaptic ionic currents with the release of neurotransmitter has been obtained  from invertebrate preparations, ...

Simultaneous Electrophysiological Recording and Calcium Imaging of Suprachiasmatic Nucleus Neurons

Simultaneous electrophysiological and fluorescent imaging recording methods were used to study the role of changes of membrane potential or current in regulating the intracellular calcium concentration. Changing environmental conditions, such as the light-dark cycle, can modify neuronal and neural network activity and the expression of a family of circadian clock genes within the suprachiasmatic nucleus (SCN), the location of the master circadian clock in the mammalian brain. Excitatory synaptic transmission leads to an increase in the postsynaptic Ca2+ concentration that is believed to activate the signaling pathways that shifts the rhythmic expression of circadian clock genes. Hypothalamic slices containing the SCN were patch clamped using microelectrodes filled with an internal solution containing the calcium indicator bis-fura-2. After a seal was formed between the microelectrode and the SCN neuronal membrane, the membrane was ruptured using gentle suction and the calcium probe diffused into the neuron filling both the soma and dendrites. Quantitative ratiometric measurements of the intracellular calcium concentration were recorded simultaneously with membrane potential or current. Using these methods it is possible to study the role of changes of the intracellular calcium concentration produced by synaptic activity and action potential firing of individual neurons. In this presentation we demonstrate the methods to simultaneously record electrophysiological activity along with intracellular calcium from individual SCN neurons maintained in brain slices.

Procedures are described to perform simultaneous recordings of membrane potential or current and changes of intracellular calcium concentration. Suprachiasmatic nucleus neurons are filled with the calcium indicator bis-fura-2 using a patch clamp electrode in the whole cell patch clamp configuration.

Eşzamanlı Elektrofizyolojik Kayıt ve Suprakiazmatik Nucleus Nöronlar Kalsiyum Görüntüleme

Simultaneous electrophysiological and fluorescent imaging recording methods were used to study the role of changes of membrane potential or current in ...

Electrophysiological Recording in the Brain of Intact Adult Zebrafish

Previously, electrophysiological studies in adult zebrafish have been limited to slice preparations or to eye cup preparations and electrorentinogram recordings. This paper describes how an adult zebrafish can be immobilized, intubated, and used for in vivo electrophysiological experiments, allowing recording of neural activity. Immobilization of the adult requires a mechanism to deliver dissolved oxygen to the gills in lieu of buccal and opercular movement. With our technique, animals are immobilized and perfused with habitat water to fulfill this requirement. A craniotomy is performed under tricaine methanesulfonate (MS-222; tricaine) anesthesia to provide access to the brain. The primary electrode is then positioned within the craniotomy window to record extracellular brain activity. Through the use of a multitube perfusion system, a variety of pharmacological compounds can be administered to the adult fish and any alterations in the neural activity can be observed. The methodology not only allows for observations to be made regarding changes in neurological activity, but it also allows for comparisons to be made between larval and adult zebrafish. This gives researchers the ability to identify the alterations in neurological activity due to the introduction of various compounds at different life stages.

This paper describes how an adult zebrafish can be immobilized, intubated, and used for in vivo electrophysiological experiments to allow recordings and manipulation of neural activity in an intact animal.

Sağlam Yetişkin Zebra balığı Beyin Elektrofizyolojik Kayıt

Previously, electrophysiological studies in adult zebrafish have been limited to slice preparations or to eye cup preparations and electrorentinogram ...

Recording Synaptic Plasticity in Acute Hippocampal Slices Maintained in a Small-volume Recycling-, Perfusion-, and Submersion-type Chamber System

Even though experiments on brain slices have been in use since 1951, problems remain that reduce the probability of achieving a stable and successful analysis of synaptic transmission modulation when performing field potential or intracellular recordings. This manuscript describes methodological aspects that might be helpful in improving experimental conditions for the maintenance of acute brain slices and for recording field excitatory postsynaptic potentials in a commercially available submersion chamber with an outflow-carbogenation unit. The outflow-carbogenation helps to stabilize the oxygen level in experiments that rely on the recycling of a small buffer reservoir to enhance the cost-efficiency of drug experiments. In addition, the manuscript presents representative experiments that examine the effects of different carbogenation modes and stimulation paradigms on the activity-dependent synaptic plasticity of synaptic transmission.

This protocol describes the stabilization of the oxygen level in a small volume of recycled buffer and methodological aspects of recording activity-dependent synaptic plasticity in submerged acute hippocampal slices.

Sinaptik plastisite akut Hipokampal dilimleri bir küçük hacimli geri dönüşüm-, perfüzyon- ve batma-tipi oda sistemi içinde tutulan kayıt

Even though experiments on brain slices have been in use since 1951, problems remain that reduce the probability of achieving a stable and successful ...

Recording Brain Electromagnetic Activity During the Administration of the Gaseous Anesthetic Agents Xenon and Nitrous Oxide in Healthy Volunteers

Anesthesia arguably provides one of the only systematic ways to study the neural correlates of global consciousness/unconsciousness. However to date most neuroimaging or neurophysiological investigations in humans have been confined to the study of &#947;-Amino-Butyric-Acid-(GABA)-receptor-agonist-based anesthetics, while the effects of dissociative N-Methyl-D-Aspartate-(NMDA)-receptor-antagonist-based anesthetics ketamine, nitrous oxide (N2O) and xenon (Xe) are largely unknown. This paper describes the methods underlying the simultaneous recording of magnetoencephalography (MEG) and electroencephalography (EEG) from healthy males during inhalation of the gaseous anesthetic agents N2O and Xe. Combining MEG and EEG data enables the assessment of electromagnetic brain activity during anesthesia at high temporal, and moderate spatial, resolution. Here we describe a detailed protocol, refined over multiple recording sessions, that includes subject recruitment, anesthesia equipment setup in the MEG scanner room, data collection and basic data analysis. In this protocol each participant is exposed to varying levels of Xe and N2O in a repeated measures cross-over design. Following relevant baseline recordings participants are exposed to step-wise increasing inspired concentrations of Xe and N2O of 8, 16, 24 and 42%, and 16, 32 and 47% respectively, during which their level of responsiveness is tracked with an auditory continuous performance task (aCPT). Results are presented for a number of recordings to highlight the sensor-level properties of the raw data, the spectral topography, the minimization of head movements, and the unequivocal level dependent effects on the auditory evoked responses. This paradigm describes a general approach to the recording of electromagnetic signals associated with the action of different kinds of gaseous anesthetics, which can be readily adapted to be used with volatile and intravenous anesthetic agents. It is expected that the method outlined can contribute to the understanding of the macro-scale mechanisms of anesthesia by enabling methodological extensions involving source space imaging and functional network analysis.

Simultaneous magnetoencephalography and electroencephalography provides a useful tool to search for common and distinct macro-scale mechanisms of reductions in consciousness induced by different anesthetics. This paper illustrates the empirical methods underlying the recording of such data from healthy humans during N-Methyl-D-Aspartate-(NMDA)-receptor-antagonist-based anesthesia during inhalation of nitrous oxide and xenon.

Kayıt beyin elektromanyetik aktivite sırasında gaz halinde olan yakıtlar anestezik ajanların Xenon ve sağlıklı gönüllü olarak azot oksit İdaresi

Anesthesia arguably provides one of the only systematic ways to study the neural correlates of global consciousness/unconsciousness. However to date most ...

Recording and Modulation of Epileptiform Activity in Rodent Brain Slices Coupled to Microelectrode Arrays

Temporal lobe epilepsy (TLE) is the most common partial complex epileptic syndrome and the least responsive to medications. Deep brain stimulation (DBS) is a promising approach when pharmacological treatment fails or neurosurgery is not recommended. Acute brain slices coupled to microelectrode arrays (MEAs) represent a valuable tool to study neuronal network interactions and their modulation by electrical stimulation. As compared to conventional extracellular recording techniques, they provide the added advantages of a greater number of observation points and a known inter-electrode distance, which allow studying the propagation path and speed of electrophysiological signals. However, tissue oxygenation may be greatly impaired during MEA recording, requiring a high perfusion rate, which comes at the cost of decreased signal-to-noise ratio and higher oscillations in the experimental temperature. Electrical stimulation further stresses the brain tissue, making it difficult to pursue prolonged recording/stimulation epochs. Moreover, electrical modulation of brain slice activity needs to target specific structures/pathways within the brain slice, requiring that electrode mapping be easily and quickly performed live during the experiment. Here, we illustrate how to perform the recording and electrical modulation of 4-aminopyridine (4AP)-induced epileptiform activity in rodent brain slices using planar MEAs. We show that the brain tissue obtained from mice outperforms rat brain tissue and is thus better suited for MEA experiments. This protocol guarantees the generation and maintenance of a stable epileptiform pattern that faithfully reproduces the electrophysiological features observed with conventional field potential recording, persists for several hours, and outlasts sustained electrical stimulation for prolonged epochs. Tissue viability throughout the experiment is achieved thanks to the use of a small-volume custom recording chamber allowing for laminar flow and quick solution exchange even at low (1 mL/min) perfusion rates. Quick MEA mapping for real-time monitoring and selection of stimulating electrodes is performed by a custom graphic user interface (GUI).

We illustrate how to perform recording and electrical modulation of 4-aminopyridine-induced epileptiform activity in rodent brain slices using microelectrode arrays. A custom recording chamber maintains tissue viability throughout prolonged experimental sessions. Live electrode mapping and selection of stimulating pairs are performed by a custom graphical user interface.

Kayıt ve modülasyon Epileptiform aktivite elektrot dizilerin birleştiğinde kemirgen beyin dilimleri içinde

Temporal lobe epilepsy (TLE) is the most common partial complex epileptic syndrome and the least responsive to medications. Deep brain stimulation (DBS) ...

Simultaneous Cryosectioning of Multiple Rodent Brains

Histology and immunohistochemistry are routine methods of analysis to visualize microscopic anatomy and localize proteins within biological tissue. In neuroscience, as well as a plethora of other scientific fields, these techniques are used. Immunohistochemistry can be done on slide mounted tissue or free-floating sections. Preparing slide-mounted samples is a time intensive process. The following protocol for a technique, called the Megabrain, reduced the time taken to cryosection and mount brain tissue by up to 90% by combining multiple brains into a single frozen block. Furthermore, this technique reduced variability seen between staining rounds, in a large histochemical study. The current technique has been optimized for using rodent brain tissue in downstream immunohistochemical analyses; however, it can be applied to different scientific fields that use cryosectioning.

Here, we present a protocol to freeze and section brain tissue from multiple animals as a timesaving alternative to processing single brains. This reduces staining variability during immunohistochemistry and reduces time cryosectioning and imaging.

Birden çok kemirgen beyin aynı anda Cryosectioning

Histology and immunohistochemistry are routine methods of analysis to visualize microscopic anatomy and localize proteins within biological tissue. In ...