Cette étude a été soutenue par la subvention du NIH (R15DA029863), la subvention Florida Atlantic University de recherche de premier cycle (M30014) et de l&#39;École de médecine vétérinaire de subvention de recherche Ross University. Nous tenons à remercier l&#39;Institut national sur l&#39;abus des drogues (Rockville, MD) pour fournir (±) 3,4-méthylènedioxyméthamphétamine (MDMA ±) pour ce travail.

Les procédures d&#39;utilisation des animaux décrits ci-dessous ont été approuvés par le Comité institutionnel de protection des animaux et l&#39;utilisation (IACUC) à l&#39;école de médecine vétérinaire de l&#39;Université de Ross et Florida Atlantic University. Bien que les techniques stériles et des gants sont nécessaires, l&#39;environnement RNase-free est pas nécessaire lors de l&#39;utilisation de ce protocole. 1. Préparation <ol><li> Préparation des tissus et de sectionnement <ol><li> Attribuer des rats au hasard en trois groupes: les frais / solution saline (SAL; NaCl 0,9%), le préfixe / SAL et préfixés / 3,4-méthylènedioxyméthamphétamine (MDMA; voir détails dans le tableau 1). </li><li> Administrer trois doses de 1 ml / kg SAL et 10 mg / kg par voie intrapéritonéale MDMA, respectivement, pour les groupes SAL et MDMA à intervalle de 2 h. Permettre aux animaux de survivre le traitement pendant 6 jours. </li><li> Au jour 7, administrer 100 mg / kg de kétamine en combinaison de 5 mg / kg par voie intrapéritonéale xylazine aux rats pour une anesthésie profonde (ie, la perte de clignotement de la cornée et tail pincer réflexes). </li><li> Pour le groupe frais / SAL, décapiter rapidement rats et enlever le cerveau pour le test de cerveau frais (voir les détails dans la référence 5). </li><li> Pour les groupes / MDMA préfixés / SAL et préfixés, faire une coupe le long du sternum environ 10 -12 cm et ensuite exposer l&#39;extrémité du sternum. </li><li> Maintenez l&#39;extrémité du sternum avec une pince hémostatique et couper la membrane latéralement des deux côtés avec des ciseaux pointus et ensuite coupé vers le haut à travers les côtes et en parallèle vers les poumons. </li><li> Avec une main, tenir la pointe ventrale du cœur avec une petite pince. Avec l&#39;autre main, percer le ventricule gauche avec une aiguille de calibre 18 de la seringue (noter le côté de l&#39;adaptateur de l&#39;aiguille est reliée à un tuyau de silicium en forme de Y Sal et paraformaldéhyde conteneurs glacées et les pompes péristaltiques, voir la référence 9). </li><li> Tournez sur la pompe de SAL au niveau moyen de la vitesse d&#39;écoulement (~ 5 ml / min) et à la perforation de l&#39;oreillette droite avec la pince pour permettre l&#39;évasion de retour circulation. Maintenir SAL perfusion pendant 30 min. </li><li> Tournez sur la pompe de paraformaldéhyde au niveau moyen et laissez la glace-paraformaldéhyde 4% froid pour perfuser l&#39;animal pendant 30 min. </li><li> Retirer l&#39;instrument de perfusion et de décapiter l&#39;animal. Faire un postéro couper à travers la ligne médiane du crâne, puis battre le crâne pour exposer la cavité du crâne 10. </li><li> Retirer le cerveau avec une spatule à partir de la cavité du crâne et du cerveau placer dans un tube à centrifuger de 50 ml contenant 25 ml de paraformaldehyde à 4%. Gardez le cerveau dans le tube contenant paraformaldéhyde à 4 ºC réfrigérateur pendant 24 h. </li><li> Déplacer le cerveau dans un tube centrifuge de 50 ml contenant 25 ml de solution de saccharose à 30% à 4 ° C pendant 3 jours. Enfin, stocker le cerveau dans les sacs en plastique à -80 ° C jusqu&#39;à utilisation. </li><li> Montez le cerveau sur un mandrin avec intégration des médias et de geler les médias enrobage contenant cerveau dans un cryostat à une température de -26 ºC. Couper le gelé fraisn cerveau cerveau en 20 sections um et le paraformaldéhyde-préfixés en sections de 10 um. Transférer la section à une lame de microscope RT en touchant la diapositive à la section. </li><li> Air sec à température ambiante pendant 4 h. Conserver les diapositives de section dans un sac étanche scellée à -80 ° C jusqu&#39;à utilisation. </li></ol></li><li> Déshydration <ol><li> Prenez diapositives de la -80 ° C congélateur et attribuer des sections dans une des trois tests: HT2A, PPIB (contrôle positif) ou dapB (contrôle négatif); marque et sections de l&#39;étiquette avec un stylo à bille (ne pas utiliser un crayon). Plonger les lames dans 100% d&#39;alcool à la température ambiante pendant 5 min. Sécher les lames pendant 5 min dans une hotte. </li></ol></li><li> Prétraitement <ol><li> Pipette 20 pl du réactif de prétraitement-1 (inactivation de la phosphatase alcaline) aux coupes sur des lames. Placer les lames sur un rail de support d&#39;une plaque à l&#39;humidité (à noter que le plateau est recouvert d&#39;un couvercle afin de maintenir une humidité élevée pour empêcher l&#39;évaporation à partir de la réaction de solution). </li><li> Secouer doucement le plateau de l&#39;humidité sur un agitateur horizontal à basse vitesse pendant 10 min. Laver les lames à deux reprises avec de l&#39;eau distillée deux fois (ddH 2 O) pendant 2 min. Immerger la lame dans un bécher de 200 ml contenant 150 ml du réactif de prétraitement-2 (rupture des liaisons transversales induites par paraformaldéhyde fixation). Faire bouillir les diapositives pour un total de 5 min à 100 ° C (de restauration induite par la chaleur de la structure de l&#39;ARN 11). </li><li> Laver les lames à deux reprises avec le trou DDH 2 O pendant 2 min. Placer les lames dans alcool à 100% pendant 5 min. Sécher les lames pendant 5 min dans la hotte. Utilisez un stylo hydrophobe pour dessiner un cercle autour de la zone sélectionnée dans la section de tissu (par exemple, des structures non-corticales, y compris le thalamus et l&#39;hypothalamus comme indiqué dans la figure 2). </li><li> Pipette 10 ul du prétraitement-3 réactif (augmentation du taux de pénétration de la sonde) à chaque zone sélectionnée, et couvrent le plateau de l&#39;humidité avec le couvercle. Placer le plateau dans le four à hybridationéquipé du agitateur horizontal et régler la température du four à 40 ºC; secouer doucement le plateau pendant 30 min. Laver les lames à deux reprises avec le trou DDH 2 O pendant 2 min. </li></ol></li></ol> 2. L&#39;hybridation et d&#39;amplification <ol><li> Pipette 10 ul de TR2A, PPIB et dapB réactifs de sonde, respectivement, sur les zones sélectionnées. Couvrir le bac d&#39;humidité avec le couvercle pour empêcher l&#39;évaporation du réactif. Secouer doucement sur l&#39;agitateur horizontal réglé à une vitesse faible. Incuber les lames à 40 ° C dans le four pendant 2 heures. </li><li> Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif d&#39;amplification-1 sur chaque zone sélectionnée, agiter et incuber les lames à 40 ° C pendant 30 min. </li><li> Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif Amplification-2 sur chaque zone sélectionnée, agiter et incuber les lames à 40 ° C pendant 15 min. </li><li> Laver les lames à deux reprises wvec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif Amplification-3 sur chaque zone sélectionnée, agiter et incuber les lames à 40 ° C pendant 30 min. </li><li> Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif Amplification-4 de chaque zone sélectionnée, agiter et incuber les lames à 40 ° C pendant 15 min. </li><li> Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif Amplification-5 sur chaque zone sélectionnée, agiter et incuber les lames à température ambiante pendant 30 min. </li><li> Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. Pipette 10 ul du réactif Amplification-6 sur chaque zone sélectionnée, agiter et incuber les lames à température ambiante pendant 15 min. Laver les lames deux fois avec un tampon de lavage pendant 2 minutes. </li></ol> 3. Signal Detection <ol><li> Introduire à la pipette 10 ul du réactif rouge à chaque région sélectionnée (A noter que le réactif est un mélange de rouge et rouge-B-A dans un rapport 1:60 et doit être utilisé immédiatement). Placer la lame dans le bac d&#39;humidité sur le agitateur horizontal à température ambiante et agiter doucement à basse vitesse pendant 10 min. </li><li> Laver les lames deux fois avec (ddH 2 O) pendant 10 min. Sécher les lames à 60 ° C dans le four pendant 15 min. Placer les lames dans le xylène sous la hotte pendant 5 min. Pipette 20 ul de milieu de montage à base de xylène sur chaque zone sélectionnée et couvrir avec une lamelle. </li></ol> 4. Capture d&#39;image <ol><li> Prenez microphotographies numériques des zones sélectionnées (par exemple, l&#39;hypothalamus, les figures 1 et 3) avec un grossissement de 4 × 20 × et des lentilles d&#39;objectif. Enregistrez le fichier d&#39;image. </li></ol> 5. Analyse des particules de l&#39;image <ol><li> Glissez et déposez le fichier de l&#39;image dans la fenêtre principale de ImageJ. Allez à la barre de menu et sélectionnez &#39;Image&#39;, suivant, sélectionnez &quot;Type&quot; dans le menu déroulant, puis sélectionnez &#39;8-bit&#39;. </li><li> Sélectionnez «Réglage», puis sélectionnez «Threshold &#39;pour ouvrir la boîte de dialogue. Réglez la valeur de barre inférieure dans la boîte de dialogue afin que le fond indésirable est retiré. Allez à la barre de menu et sélectionnez «Analyser», puis sélectionnez «analyser des particules &#39;pour ouvrir une deuxième boîte de dialogue. </li><li> Régler la taille des particules à 10, sélectionner la prochaine &#39;Show présente »et sélectionnez« Afficher les résultats »et« boîtes Résumer&#39;. Enfin, cliquez sur «OK» pour afficher les données de particules dans les boîtes de dialogue. </li></ol> 6. Calcul Spreadsheet <ol><li> Saisissez les données dans la feuille Excel et en moyenne le nombre de particules dans le groupe SAL comme base de référence. Calculer le niveau de pourcentage de chaque section et faire un graphique en conséquence (Figure 4). </li></ol>

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Les auteurs déclarent qu&#39;ils ont aucun intérêt financier concurrentes.

One of the major concerns of in situ hybridization test is to choose appropriate techniques used for RNA preservation because of RNase enzymes. It is well known that these enzymes are widely present in the cells and environment which can affect the results. However, enzyme activity can be quickly distinguished by placing the tissue in the dry ice/alcohol solution5,12. Although quick preservation is critical for hybridization using a riboprobe13, little is known about experimental conditions...

Serotonin (5-hydroxytryptamine; 5-HT) syndrome is an acute neurologic disorder caused by 5-HT-promoting drugs such as antidepressants1, while also occurring in situations of MDMA use for recreational purposes2. Molecular mechanisms responsible for mood swings, learning and memory deficits that occur in association with the acute syndrome are not well understood3,4. In situ hybridization is a powerful research tool allowing the detection and quantification of specific mRNAs expressed potentially at a single-cell level. The conventional way to perform in situ hybridization is to utilize a radioactive-labeled riboprobe that specifically hybridizes the gene of interest. However, a major drawback is that the method requires complicated and time-consuming probe preparation and hybridization steps, as well as access to fresh frozen tissues maintained in an RNase-free environment5,6. 
Oligonucleotide probes have been recently developed to hybridize shorter RNA fragments than those required for riboprobes7. Furthermore, the probes produce a low background signal without sacrificing specificity8. This newly-developed probe technology can be used in situ hybridization on paraformaldehyde-prefixed brain tissues commonly available in immunocytochemical laboratories.
Here, we describe a protocol for in situ hybridization using oligonucleotide probes on paraformaldehyde-prefixed rat brain and compare findings with those noted in a fresh frozen brain5,6. This protocol is used to test the hypothesis that MDMA substance abuse causes changes in 5-HT2A receptor gene htr2a mRNA in the brain. We began the procedure with MDMA treatment followed by paraformaldehyde tissue perfusion of the animal, in situ hybridization of the thr2a probe, and data analysis. Note that dapB (the bacterial gene coding for dihydrodipicolinate reductase) is used as a negative control, and ppiB (housekeeping gene coding for peptidylprolyl isomerase B) as a positive control.

<table border="0" cellpadding="0" cellspacing="0" width="873">
	<tbody>
		<tr>
			<td>RNAscope Negative Control Probe-DapB</td>
			<td>Advanced cell diagnostic, INC</td>
			<td>310098</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAscope Pretreat 4</td>
			<td>Advanced cell diagnostic, INC</td>
			<td>320046</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAscope 2.0 HD Reagent Kit - Red</td>
			<td>Advanced cell diagnostic, INC</td>
			<td>310036</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAscope Probe - Rn-Ppib</td>
			<td>Advanced cell diagnostic, INC</td>
			<td>313921</td>
			<td></td>
		</tr>
		<tr>
			<td>Rat Htr2a</td>
			<td>Advanced cell diagnostic, INC</td>
			<td>300031</td>
			<td></td>
		</tr>
		<tr>
			<td>Cryostat</td>
			<td>Leica</td>
			<td>CM 1850</td>
			<td></td>
		</tr>
		<tr>
			<td>Horizontal shaker</td>
			<td>VWR</td>
			<td>88032-088</td>
			<td></td>
		</tr>
		<tr>
			<td>Hybridization oven</td>
			<td>Thermo Fisher Scientific</td>
			<td>222000</td>
			<td></td>
		</tr>
		<tr>
			<td>Superfrost Plus microscope slide</td>
			<td>Fisher Scientific</td>
			<td>12-550-15</td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrophobic pen</td>
			<td>Vector</td>
			<td>H-4000</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope</td>
			<td>Olympus</td>
			<td>Provis AX70</td>
			<td></td>
		</tr>
	</tbody>
</table>

rapid in situ hybridization using oligonucleotide probes on paraformaldehyde-prefixed brain of rats with serotonin syndrome

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) toxicity may cause region-specific changes in serotonergic mRNA expression due to acute serotonin (5-hydroxytryptamine; 5-HT) syndrome. This hypothesis can be tested using in situ hybridization to detect the serotonin 5-HT2A receptor gene htr2a. In the past, such procedures, utilizing radioactive riboprobe, were difficult because of the complicated workflow that needs several days to perform and the added difficulty that the technique required the use of fresh frozen tissues maintained in an RNase-free environment. Recently, the development of short oligonucleotide probes has simplified in situ hybridization procedures and allowed the use of paraformaldehyde-prefixed brain sections, which are more widely available in laboratories. Here, we describe a detailed protocol using non-radioactive oligonucleotide probes on the prefixed brain tissues. Hybridization probes used for this study include dapB (a bacterial gene coding for dihydrodipicolinate reductase), ppiB (a housekeeping gene coding for peptidylprolyl isomerase B), and htr2a (a serotonin gene coding for 5-HT2A receptors). This method is relatively simply, cheap, reproducible and requires less than two days to complete.

En utilisant les sondes d&#39;ARN oligonucléotidique (&lt;25 nt), l&#39;hybridation peut être détectée sous forme de points rouges dans les cellules de l&#39;hypothalamus préparés à partir de cerveaux congelés paraformaldehyde préfixée et frais. Les molécules d&#39;ARNm HTR2A sont présents dans certaines cellules (indiquées par les flèches solides), mais pas d&#39;autres (flèches ouvertes). Nous avons observé qu&#39;il n&#39;y a pas de différence entre le paraformaldehyde préfixée et les tiss...

Watch this Scientific Journal Video about Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome at JoVE.com

Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome

This protocol describes a rapid and simplified in situ hybridization method ideal forparaformaldehyde-prefixed brain, thus reducing the need for prolonged complex steps while using fresh frozen tissues. The method is validated using the identification of the serotonin 5-HT2A receptor gene htr2a in rats.

Rapid<em&gt; In Situ</em&gt; Hybridation utilisant sondes oligonucléotidiques sur Brain Paraformaldéhyde préfixée de rats avec syndrome sérotoninergique

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) toxicity may cause region-specific changes in serotonergic mRNA expression due to acute serotonin ...

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Neuroscience

Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome

8.8K vues.  Ross University School of Veterinary Medicine. This protocol describes a rapid and simplified in situ hybridization method ideal forparaformaldehyde-prefixed brain, thus reducing the need for prolonged complex steps while using fresh frozen tissues. The method is validated using the identification of the serotonin 5-HT2A receptor gene htr2a in rats.

Vidéo: Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome

Double Fluorescence in situ Hybridization in Fresh Brain Sections

Here we describe a modified version of a double fluorescence in situ hybridization (dFISH) method optimized for detecting two mRNAs of interest in fresh frozen brain sections. Our group has successfully used this approach to study gene co-regulation. More specifically, we have used this dFISH method to explore the anatomical organization, neurochemical properties, and the impact of sensory experience in central sensory circuits, at single cell resolution. This protocol has been validated in brain tissue from mice, rats and songbirds but is expected to be easily adaptable to other vertebrate species, as well as to an array of non-neural tissues. In this film we provide a detailed demonstration of the main steps of this procedure.

Double Fluorescence in situ Hybridization in Fresh Brain Sections

This protocol involves a non-radioactive in-situ hybridization procedure that enables the simultaneous identification of two transcript species, at a single cell resolution, in thin sections of the vertebrate brain.

Double fluorescence In situ</emHybridation> dans des coupes de cerveau frais

Here we describe a modified version of a double fluorescence in situ hybridization (dFISH) method optimized for detecting two mRNAs of interest in fresh ...

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Neurosciences

TMS: Using the Theta-Burst Protocol to Explore Mechanism of Plasticity in Individuals with Fragile X Syndrome and Autism

Fragile X Syndrome (FXS), also known as Martin-Bell Syndrome, is a genetic abnormality found on the X chromosome.1,2 Individuals suffering from FXS display abnormalities in the expression of FMR1 - a protein required for typical, healthy neural development.3 Recent data has suggested that the loss of this protein can cause the cortex to be hyperexcitable thereby affecting overall patterns of neural plasticity.4,5
In addition, Fragile X shows a strong comorbidity with autism: in fact, 30% of children with FXS are diagnosed with autism, and 2 - 5% of autistic children suffer from FXS.6
Transcranial Magnetic Stimulation (a non-invasive neurostimulatory and neuromodulatory technique that can transiently or lastingly modulate cortical excitability via the application of localized magnetic field pulses 7,8) represents a unique method of exploring plasticity and the manifestations of FXS within affected individuals. More specifically, Theta-Burst Stimulation (TBS), a specific stimulatory protocol shown to modulate cortical plasticity for a duration up to 30 minutes after stimulation cessation in healthy populations, has already proven an efficacious tool in the exploration of abnormal plasticity.9,10 
Recent studies have shown the effects of TBS last considerably longer in individuals on the autistic spectrum - up to 90 minutes.11 This extended effect-duration suggests an underlying abnormality in the brain's natural plasticity state in autistic individuals - similar to the hyperexcitability induced by Fragile X Syndrome.
In this experiment, utilizing single-pulse motor-evoked potentials (MEPs) as our benchmark, we will explore the effects of both intermittent and continuous TBS on cortical plasticity in individuals suffering from FXS and individuals on the Autistic Spectrum.

In this article, we examine the effects of Theta-Burst TMS stimulation on cortical plasticity in individuals suffering from Fragile X syndrome and individuals on the autistic spectrum.

TMS: Utilisation du protocole Theta-Burst à explorer Mechasnism de la plasticité chez les individus atteints du syndrome du X fragile et autisme

Fragile X Syndrome (FXS), also known as Martin-Bell Syndrome, is a genetic abnormality found on the X chromosome.1,2 Individuals suffering from FXS ...

Combining Lipophilic dye, in situ Hybridization, Immunohistochemistry, and Histology

Going beyond single gene function to cut deeper into gene regulatory networks requires multiple mutations combined in a single animal. Such analysis of two or more genes needs to be complemented with in situ hybridization of other genes, or immunohistochemistry of their proteins, both in whole mounted developing organs or sections for detailed resolution of the cellular and tissue expression alterations. Combining multiple gene alterations requires the use of cre or flipase to conditionally delete genes and avoid embryonic lethality. Required breeding schemes dramatically enhance effort and cost proportional to the number of genes mutated, with an outcome of very few animals with the full repertoire of genetic modifications desired. Amortizing the vast amount of effort and time to obtain these few precious specimens that are carrying multiple mutations necessitates tissue optimization. Moreover, investigating a single animal with multiple techniques makes it easier to correlate gene deletion defects with expression profiles. We have developed a technique to obtain a more thorough analysis of a given animal; with the ability to analyze several different histologically recognizable structures as well as gene and protein expression all from the same specimen in both whole mounted organs and sections. Although mice have been utilized to demonstrate the effectiveness of this technique it can be applied to a wide array of animals. To do this we combine lipophilic dye tracing, whole mount in situ hybridization, immunohistochemistry, and histology to extract the maximal possible amount of data.

Combining Lipophilic dye, in situ Hybridization, Immunohistochemistry, and Histology

A combination of different techniques to maximize data collection from mouse tissue is presented.

Combinant colorant lipophile, In situ</emHybridation>, immunohistochimie et l&#39;histologie

Going beyond single gene function to cut deeper into gene regulatory networks requires multiple mutations combined in a single animal.  Such analysis of ...

Rapid Determination of the Thermal Nociceptive Threshold in Diabetic Rats

Painful diabetic neuropathy (PDN) is characterized by hyperalgesia i.e., increased sensitivity to noxious stimulus, and allodynia i.e., hypersensitivity to normally innocuous stimuli1. Hyperalgesia and allodynia have been studied in many different rodent models of diabetes mellitus2. However, as stated by B&ouml;lcskei et al, determination of "pain" in animal models is challenging due to its subjective nature3. Moreover, the traditional methods used to determine behavioral responses to noxious thermal stimuli usually lack reproducibility and pharmacological sensitivity3. For instance, by using the hot-plate method of Ankier4, flinch, withdrawal and/or licking of either hind- and/or fore-paws is quantified as reflex latencies at constant high thermal stimuli (52-55 &deg;C). However, animals that are hyperalgesic to thermal stimulus do not reproducibly show differences in reflex latencies using those supra-threshold temperatures3,5. As the recently described method of B&ouml;lcskei et al.6, the procedures described here allows for the rapid, sensitive and reproducible determination of thermal nociceptive thresholds (TNTs) in mice and rats. The method uses slowly increasing thermal stimulus applied mostly to the skin of mouse/rat plantar surface. The method is particularly sensitive to study anti-nociception during hyperalgesic states such as PDN. The procedures described bellow are based on the ones published in detail by Alm&aacute;si et al 5 and B&ouml;lcskei et al 3. The procedures described here have been approved the Laboratory Animal Care and Use Committee (LACUC), Wright State University.

Here, we describe a rapid reliable and simple procedure to determine the lowest temperature at which rats or mice show nocifensive behavior, i.e. the thermal nociceptive threshold (TNT). This method applies a slowly increasing thermal stimulus allowing precise and reproducible estimation of TNTs with minimum, if any, stress to the animals.

Détermination rapide du seuil thermique nociceptive chez les rats diabétiques

Painful diabetic neuropathy (PDN) is characterized by hyperalgesia i.e., increased sensitivity to noxious stimulus, and allodynia i.e., hypersensitivity ...

Complete Spinal Cord Injury and Brain Dissection Protocol for Subsequent Wholemount In Situ Hybridization in Larval Sea Lamprey

After a complete spinal cord injury, sea lampreys at first are paralyzed below the level of transection. However, they recover locomotion after several weeks, and this is accompanied by short distance regeneration (a few mm) of propriospinal axons and spinal-projecting axons from the brainstem. Among the 36 large identifiable spinal-projecting neurons, some are good regenerators and others are bad regenerators. These neurons can most easily be identified in wholemount CNS preparations. In order to understand the neuron-intrinsic mechanisms that favor or inhibit axon regeneration after injury in the vertebrates CNS, we determine differences in gene expression between the good and bad regenerators, and how expression is influenced by spinal cord transection. This paper illustrates the techniques for housing larval and recently transformed adult sea lampreys in fresh water tanks, producing complete spinal cord transections under microscopic vision, and preparing brain and spinal cord wholemounts for in situ hybridization. Briefly, animals are kept at 16&#160;&#176;C and anesthetized in 1% Benzocaine in lamprey Ringer. The spinal cord is transected with iridectomy scissors via a dorsal approach and the animal is allowed to recover in fresh water tanks at 23 &#176;C. For in situ hybridization, animals are reanesthetized and the brain and cord removed via a dorsal approach.

Complete Spinal Cord Injury and Brain Dissection Protocol for Subsequent Wholemount In Situ Hybridization in Larval Sea Lamprey

Lampreys recover locomotion after a complete spinal cord injury. However, some spinal-projecting neurons are good regenerators and others are not. This paper illustrates the techniques for housing sea lamprey larvae (and recently transformed adults), producing complete spinal cord transections and preparing wholemount brains and spinal cords for in situ hybridization.

Spinal Cord Injury complète et cerveau Protocole Dissection pour Wholemount suite<em&gt; In Situ</em&gt; Hybridation dans des larves de la lamproie marine

After a complete spinal cord injury, sea lampreys at first are paralyzed below the level of transection. However, they recover locomotion after several ...

Detection of Axonally Localized mRNAs in Brain Sections Using High-Resolution In Situ Hybridization

mRNAs are frequently localized to vertebrate axons and their local translation is required for axon pathfinding or branching during development and for maintenance, repair or neurodegeneration in postdevelopmental periods. High throughput analyses have recently revealed that axons have a more dynamic and complex transcriptome than previously expected. These analysis, however have been mostly done in cultured neurons where axons can be isolated from the somato-dendritic compartments. It is virtually impossible to achieve such isolation in whole tissues in vivo. Thus, in order to verify the recruitment of mRNAs and their functional relevance in a whole animal, transcriptome analyses should ideally be combined with techniques that allow the visualization of mRNAs in situ. Recently, novel ISH technologies that detect RNAs at a single-molecule level have been developed. This is especially important when analyzing the subcellular localization of mRNA, since localized RNAs are typically found at low levels. Here we describe two protocols for the detection of axonally-localized mRNAs using a novel ultrasensitive RNA ISH technology. We have combined RNAscope ISH with axonal counterstain using fluorescence immunohistochemistry or histological dyes to verify the recruitment of Atf4 mRNA to axons in vivo in the mature mouse and human brains.

Detection of Axonally Localized mRNAs in Brain Sections Using High-Resolution In Situ Hybridization

RNA in situ hybridization (ISH) enables the visualization of RNAs in cells and tissues. Here we show how combination of RNAscope ISH with immunohistochemistry or histological dyes can be successfully used to detect mRNAs localized to axons in sections of mouse and human brains.

Détection de axonaux localisée ARNm dans les sections de cerveau en utilisant haute résolution<em&gt; In Situ</em&gt; Hybridation

mRNAs are frequently localized to vertebrate axons and their local translation is required for axon pathfinding or branching during development and for ...

Combining Double Fluorescence In Situ Hybridization with Immunolabelling for Detection of the Expression of Three Genes in Mouse Brain Sections

Detection of gene expression in different types of brain cells e.g., neurons, astrocytes, oligodendrocytes, oligodendrocyte precursors and microglia, can be hampered by the lack of specific primary or secondary antibodies for immunostaining. Here we describe a protocol to detect the expression of three different genes in the same brain section using double fluorescence in situ hybridization with two gene-specific probes followed by immunostaining with an antibody of high specificity directed against the protein encoded by a third gene. The Aspartoacyclase (ASPA) gene, mutations of which can lead to a rare human white matter disease - Canavan disease - is thought to be expressed in oligodendrocytes and microglia but not in astrocytes and neurons. However, the precise expression pattern of ASPA in the brain has yet to be established. This protocol has allowed us to determine that ASPA is expressed in a subset of mature oligodendrocytes and it can be generally applied to a wide range of gene expression pattern studies.

Combining Double Fluorescence In Situ Hybridization with Immunolabelling for Detection of the Expression of Three Genes in Mouse Brain Sections

Localizing gene expression to specific cell types can be challenging due to the lack of specific antibodies. Here we describe a protocol for simultaneous triple detection of gene expression by combining double fluorescence RNA in situ hybridization with immunostaining.

Combinant Double Fluorescence<em&gt; In Situ</em&gt; Hybridation avec Immunomarquage pour la détection de l&#39;expression de trois gènes chez la souris Sections du cerveau

Detection of gene expression in different types of brain cells e.g., neurons, astrocytes, oligodendrocytes, oligodendrocyte precursors and microglia, can ...

Recording EEG in Freely Moving Neonatal Rats Using a Novel Method

EEG is a useful method to detect electrical activity in the brain. Moreover, it is a widely used diagnostic tool for various neurological conditions, such as epilepsy and neurodegenerative disorders. However, it is technically difficult to obtain EEG recordings in neonates as it requires specialized handling and great care. Here, we present a novel method to record EEG in neonatal rat pups (P8-P15). We designed a simple and reliable electrode using computer pin loci; it can be easily implanted into the skull of a rat pup to record high-quality EEG signals in the normal and epileptic brain. Pups were given an intraperitoneal (i.p.) injection of the neurotoxin kainic acid (KA) to induce epileptic seizures. The surgical implantation performed in this procedure is less expensive than other EEG procedures for neonates. This method allows one to record high-quality and stable EEG signals for more than 1 week. Furthermore, this procedure can also be applied to adult rats and mice to study epilepsy or other neurological disorders.

Here, we introduce a novel technique designed to record electroencephalography (EEG) in freely moving neonatal epileptic pups and describe its procedures, features, and applications. This method allows one to record EEG for more than 1 week.

Enregistrement d&#39;EEG dans des rats néonatals à déplacement libre à l&#39;aide d&#39;une nouvelle méthode

EEG is a useful method to detect electrical activity in the brain. Moreover, it is a widely used diagnostic tool for various neurological conditions, such ...

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory Receptor Neurons (ORNs) housed in hair-like structures, called chemosensilla, of the antennae. On the ORNs&#39; membranes, Odorant Receptors (ORs) are believed to be involved in odor coding. Thus, being able to identify genes localized to the ORNs is necessary to recognize OR genes, and provides a fundamental basis for further functional in situ studies. The RNA expression levels of specific ORs in insect antennae are very low, and preserving insect tissue for histology is challenging. Thus, it is difficult to localize an OR to a specific type of sensilla using RNA in situ hybridization. In this paper, a detailed and highly effective RNA in situ hybridization protocol particularly for lowly expressed OR genes of insects, is introduced. In addition, a specific OR gene was identified by conducting double-color fluorescent in situ hybridization experiments using a co-expressing receptor gene, Orco, as a marker.

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

This paper describes a detailed and highly effective RNA in situ hybridization protocol particularly for low-level expressed Odorant Receptor (OR) genes, as well as other genes, in insect antennae using digoxigenin (DIG)-labeled or biotin-labeled probes.

Localisation des gènes des récepteurs odorants dans les antennes acridiennes par ARN<em&gt; In Situ</em&gt; Hybridation

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory ...

Induction of Diffuse Axonal Brain Injury in Rats Based on Rotational Acceleration

Traumatic brain injury (TBI) is a major cause of death and disability. Diffuse axonal injury (DAI) is the predominant mechanism of injury in a large percentage of TBI patients requiring hospitalization. DAI involves widespread axonal damage from shaking, rotation or blast injury, leading to rapid axonal stretch injury and secondary axonal changes that are associated with a long-lasting impact on functional recovery. Historically, experimental models of DAI without focal injury have been difficult to design. Here we validate a simple, reproducible and reliable rodent model of DAI that causes widespread white matter damage without skull fractures or contusions.

This protocol validates a reliable, easy-to-perform and reproducible rodent model of brain diffuse axonal injury (DAI) that induces widespread white matter damage without skull fractures or contusions.

Induction de lésion diffuse du cerveau axonal chez les rats basés sur l’accélération rotationnelle

Traumatic brain injury (TBI) is a major cause of death and disability. Diffuse axonal injury (DAI) is the predominant mechanism of injury in a large ...