This work was supported by the Australian Research Council Centre of Excellence for Integrative Brain Function (ARC Centre Grant CE140100007), an NHMRC project grant (#1086643). Prof. George Paxinos is supported by a Senior Principal Research Fellow NHMRC grant (#1043626).

Etica Dichiarazione: Tutte le procedure che coinvolgono soggetti animali seguono le linee guida del Comitato Animal Care and Ethics (ACEC) presso l&#39;Università del New South Wales (il numero ACEC approvato è di 14 / 94A). 1. Preparazione del cavo del mouse trasparente spinale <ol><li> Preparazione di Ice Cold Hydrogel Soluzione <ol><li> Preparazione della soluzione di paraformaldeide al 16% (PFA) <ol><li> Aggiungere 16 g di polvere di paraformaldeide in 70 ml-pre riscaldato acqua distillata (50-55 ° C) e mescolare su un agitatore magnetico riscaldata fino paraformaldeide si scioglie. Nota: Non lasciare che la soluzione per il riscaldamento oltre 55 ° C ed essere consapevoli del fatto che paraformaldeide è tossico. </li><li> Trasferire la soluzione paraformaldeide ad un cilindro e aggiungere acqua distillata fino a 100 ml. Raffreddare la soluzione paraformaldeide utilizzando un C frigorifero a 4 °. </li></ol></li><li> Sciogliere 125 mg VA-044 iniziatore 26,25 ml di acqua distillata e raffreddare la soluzione in un 4° C frigo. </li><li> Raffreddare 5 ml di soluzione di acrilammide (40%), 1,25 ml di soluzione di bis (2%) (ATTENZIONE: Bis e le soluzioni di acrilamide sono tossici, può causare difetti genetici o il cancro), 5 ml di 10X PBS, 12,5 ml al 16% soluzione PFA, e la soluzione di iniziatore VA-044 su ghiaccio. </li><li> Mescolare le soluzioni sopra sul ghiaccio. Nota: il volume totale è di 50 ml. </li></ol></li><li> Perfusione e Raccolta del cavo del mouse spinale <ol><li> Anestetizzare un mouse con un&#39;iniezione intraperitoneale di ketamina (80 mg / kg) e xyzaline (5 mg / kg) diluito in soluzione fisiologica 0,9% normale. Il dosaggio per mouse può essere inferiore a quello dei ratti. </li><li> Su una superficie di plastica adatta in una cappa aspirante, fissare gli arti del mouse lontano dal corpo (nastro adesivo è efficace) una volta che il mouse non risponde a una presa per la sua pelle del piede. </li><li> Tagliare la pelle del mouse sopra il petto e poi il torace osso per esporre il cuore con una forbice. </li><li> Utilizzando una pompa peristaltica, con un ago 25 G collegato a the estremità del tubo, inserire l&#39;ago nel ventricolo sinistro del cuore, snip l&#39;atrio destro per creare un punto di uscita per il sangue e quindi avviare il lavaggio con 40 ml 0,9% soluzione fisiologica una velocità di circa 10 ml / min. </li><li> Al termine, profumato il mouse con 35 ml di ghiaccio soluzione idrogel freddo. Nota: profumato ad una velocità di 10 ml / min per evitare gonfiore del tessuto nervoso. </li><li> Incidere la pelle sul dorso con una lama e quindi rimuovere i muscoli vicino al vertebrati. Dopo il taglio archi vertebrali da un lato e facendoli ruotare verso l&#39;altro lato, prendere il midollo spinale dalla colonna vertebrale, con una multa forbice. </li></ol></li><li> Cancellazione del cavo del mouse spinale <ol><li> Posizionare il midollo spinale in 15 ml di soluzione di idrogel notte a 4 ° C. </li><li> Rimuovere 10 ml della soluzione di idrogel e versare il resto della soluzione con i segmenti del midollo spinale in una provetta 5 ml. Riempire il tubo 5 ml con la soluzione di idrogel fino a quando non è completamente pieno. </li><li> Stretch un piccolo pezzo di parafilm sopra la parte superiore del tubo 5 ml e poi avvolgere parafilm intorno al collo del tubo. Nota: Assicurarsi che i contatti parafilm la soluzione idrogel e non vi siano bolle tra la soluzione idrogel e il parafilm. </li><li> Inserire il tubo 5 ml a 37 &#160; ° C forno durante la notte. Osservare la soluzione idrogel fino a farla diventare un gel. </li><li> Prendere il tubo 5 ml dal forno e rimuovere il gel dal tubo con una chiave (come un shoveled 1 ml puntale). Rimuovere il gel dal tessuto del midollo spinale da attaccare il tessuto grossolano al gel e poi prendere il tessuto grossolano di distanza (il gel si attacca al tessuto e quindi sarà rimosso dal tessuto). </li><li> Dopo aver rimosso il gel dal tessuto del midollo spinale, lavare il midollo spinale 4 volte con PBS 1x (pH 7,4) per 24 ore su un agitatore. </li><li> Preparare la soluzione di compensazione CUBIC sciogliendo 3,85 g di urea e 3,85 g N, N, N &#39;, N&#39;-tetrakis (2-idrossipropil) ethylenediamine a 5.38 ml di acqua distillata. Nota: Un agitatore caldo viene utilizzato. Aggiungere 2,31 g di polietilene glicole mono-p-isooctylphenyl etere / Triton X-100 alla soluzione una volta che è chiaro e si raffredda a temperatura ambiente. Nota: 10 g di questi tre sostanze chimiche sono per un mouse. </li><li> Tagliare il mouse midollo spinale coronale in segmenti lunghi 2-3 mm con una lametta e metterli in 5 ml di soluzione di compensazione CUBIC sopra. Posizionare su un agitatore in forno a 37 &#160; ° C per 3 giorni. </li><li> Tre giorni dopo, cambiare la soluzione di compensazione per una nuova. Nota: la suddetta soluzione viene preparata prima dell&#39;uso. </li><li> Due o tre giorni più tardi, dopo l&#39;aggiornamento della soluzione di compensazione CUBIC, controllare la trasparenza del tessuto contro una carta con carattere 8 lettere. Se è trasparente, le lettere sono visibili attraverso il tessuto eliminato. Rimuovere la soluzione di compensazione e aggiungere 4 ml di PBST (0,1% Triton-X100) per lavare il tessuto 4 volte al giorno (ogni 6 ore). </li></ol></li></ol><ol><li> Incubare i segmenti del midollo spinale nella soluzione di anticorpo primario (anti-serotonina, cresciuto a coniglio, diluito 1: 100 in PBST) per 3 giorni su un agitatore in forno a 37 °. </li><li> Rimuovere la soluzione di anticorpi e aggiungere 4 ml di PBST (0,1% Triton-X100) per lavare i segmenti del midollo spinale 4 volte al giorno (ogni 6 ore) in un forno a 37 ° C. </li><li> Rimuovere la soluzione PBST e aggiungere la soluzione di anticorpo secondario (594 coniugato capra anti-IgG di coniglio, diluito 1: 100 in PBST) incubare il tessuto per 3 giorni su un agitatore in forno a 37 °. </li><li> Rimuovere la soluzione di anticorpo secondario e aggiungere 4 ml di PBST per lavare i segmenti del midollo spinale 4 volte al giorno (ogni 6 ore) su un agitatore in forno a 37 °. Il giorno successivo il tessuto è pronto per l&#39;imaging. </li></ol> 3. Imaging <ol><li> Rimuovere la soluzione PBST e aggiungere 4 ml di 85% glicerolo per rendere l&#39;indice di rifrazione del tessuto anche. </li><li&gt; Controllare la chiarezza del tessuto. Una volta chiarito in circa 1 ora, mettere il tessuto su una grande, scivolo vetro sottile che si adatta il telaio del multi-photo fluorescente microscopio tenuta. </li><li> Mettere qualche goccia di 85% glicerolo accanto al tessuto del midollo spinale e applicare il coprioggetto con un bicchiere coprioggetto 22 x 50 mm 2. Nota: L&#39;orientamento del midollo spinale decide come l&#39;immagine assomiglia. </li><li> Mettere il vetrino sul telaio del microscopio a fluorescenza multi-photon tenuta e spostare il tessuto nel percorso della luce. </li><li> Scegliere l&#39;elio neon linea laser 594 nm e regolare l&#39;intensità del laser al livello ottimale controllando la luminosità del segnale positivo nell&#39;immagine live. </li><li> Selezionare l&#39;area di scansione del tessuto del midollo spinale con l&#39;obiettivo 20X (in acqua, NA 0,7) e preparare per creare un z-stack, e la profondità di ogni passo impostato a 3 micron. </li><li> Acquisire il tessuto dalla parte superiore alla parte inferiore del z-stack sotto la obiet 20Xtiva e quindi obiettivo 63X (in olio, NA 1.4) (dimensione del passo è stato di 1 micron), rispettivamente. Ricostruire i video 3D utilizzando un software 3D 28. </li></ol>

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The authors have nothing to disclose.

Il protocollo descritto mostra come le fibre immagine serotoninergici nel topo midollo spinale con la chiarezza combinato e tecniche di cubi. Si introduce un processo di compensazione più veloce rispetto al protocollo di compensazione passiva sviluppato da Cheung et al. 14 e Tomer et al. 15 e permette il tessuto del midollo spinale per essere ben supportato dal idrogel durante compensazione. Un passo importante durante la fissazione del mouse midollo ...

Supraspinal projections are responsible for the modulation of diverse behaviors such as pain perception. One of the projections carrying nociceptive information contains serotoninergic fibers, which originate from the hindbrain raphe and adjacent reticular nuclei1,2. Physiological and pharmacological studies have demonstrated an increased release of serotonin in the dorsal horn of the spinal cord after electrical stimulation of the raphe nuclei in the hindbrain3-5. In the rat and opossum, serotonergic raphespinal fibers have dense terminals, not only in the dorsal horn6-8, but also in the intermediate zone7,9,10, the ventral horn7,11, and even lamina 1012,13. There are no similar studies in the mouse. The present study aimed to map the termination pattern of serotonergic fibers arising from the hindbrain raphe nuclei and their adjacent reticular nuclei in the mouse spinal cord using the recently published CLARITY14 method and its modification - CUBIC15. 
Conventional fluorescence or peroxidase immunohistochemistry of the spinal cord clearly shows the distribution of serotonergic fibers in the gray matter of the spinal cord in 30-40 &#181;m thick cross-sections. However, this approach does not show the continuity of the serotonergic fiber tracts in the white matter and their collaterals in the gray matter. Although the 3D reconstruction of histological sections has advanced our knowledge of fiber tracts, it remains a challenge for histologists and anatomists to follow a single tract due to small distortions in the tissue caused by cutting. To circumvent this obstacle a number of researchers have developed various protocols for making the whole tissue structure transparent, and collecting an image of unaltered tissue in a single video file17-21. So far, the clear, lipid-exchanged, acrylamide-hybridized rigid, imaging/ immunostaining compatible, tissue hydrogel (CLARITY) technique, developed by Deisseroth's group14,15, as well as CUBIC, developed by Susaki et al16 are the most successful. Since the publication of the protocols, many researchers have started using these techniques to investigate various aspects of biological tissues, including, not only the brain22-25, but also the heart, kidneys, intestine, and the lungs26,27. 
By fixing the mouse spinal cord with the hydrogel solution (CLARITY) and clearing with the CUBIC reagents (which is a much faster method than that described by the original CLARITY protocol14,15), a spinal cord tissue block of 2-3 mm long was cleared within two weeks and immunofluorescence staining for serotonin completed in eight days. With just a combination of chemical agents, conventional immunohistochemistry can be used to create an image of individual fiber tracts in a 3D video file in approximately one month.

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	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:495px;">Photoinitiator VA044</td>
			<td style="width:495px;">Wako</td>
			<td style="width:284px;">va-044/225-02111</td>
			<td style="width:807px;">http://www.wako-chem.co.jp/specialty/waterazo/VA-044.htm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">40% acrylamide solution</td>
			<td>Bio Rad</td>
			<td>161-0140</td>
			<td>http://www.bio-rad.com/en-au/sku/161-0140-40-acrylamide-solution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2% Bis Solution</td>
			<td>Bio Rad</td>
			<td>161-0142</td>
			<td>http://www.bio-rad.com/en-au/sku/161-0142-2-bis-solution?parentCategoryGUID=5e7a4f31-879c-4d63-ba0b-82556a0ccf1d</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">paraformaldehyde</td>
			<td>Sigma</td>
			<td align="right">158127</td>
			<td>http://www.sigmaaldrich.com/catalog/product/sial/158127?lang=en&#38;region=AU</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">urea</td>
			<td>Merck Millipore</td>
			<td align="right">66612</td>
			<td>http://www.merckmillipore.com/AU/en/product/Urea---CAS-57-13-6---Calbiochem,EMD_BIO-66612</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N,N,N&#8217;,N&#8217;-tetrakis (2-hydroxypropyl) ethylenediamine</td>
			<td>Merck Millipore</td>
			<td align="right">821940</td>
			<td>http://www.merckmillipore.com/AU/en/product/Ethylenediamine-N,N,N&#39;,N&#39;-tetra-2-propanol,MDA_CHEM-821940</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Triton-X 100</td>
			<td>Merck Millipore</td>
			<td align="right">648462</td>
			<td>http://www.merckmillipore.com/AU/en/product/TRITON&#174;-X-100-Detergent---CAS-9002-93-1---Calbiochem,EMD_BIO-648462</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sucrose</td>
			<td>Sigma</td>
			<td>S0389</td>
			<td>http://www.sigmaaldrich.com/catalog/product/sigma/s0389?lang=en&#38;region=AU</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2,2&#8217;,2&#8217;&#8217;- nitrilotriethanol</td>
			<td>Merck Millipore</td>
			<td align="right">137002</td>
			<td>http://www.merckmillipore.com/AU/en/product/Triethanolamine-(Trolamine),MDA_CHEM-137022</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">serotonin antibody</td>
			<td>Merck Millipore</td>
			<td>AB938</td>
			<td>http://www.merckmillipore.com/AU/en/product/Anti-Serotonin-Antibody,MM_NF-AB938</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">goat anti rabbit IgG (H+L) Secondary Antibody, Alexa Fluor&#174; 594 conjugate</td>
			<td>Life Technologies</td>
			<td>&#160;A-11012</td>
			<td>https://www.lifetechnologies.com/order/genome-database/antibody/Rabbit-IgG-H-L-Secondary-Antibody-Polyclonal/A-11012</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">multi-photon microscope</td>
			<td>Leica</td>
			<td>Leica TCS SP5 MP STED</td>
			<td>http://www.leica-microsystems.com/products/confocal-microscopes/details/product/leica-tcs-sp5-mp/</td>
		</tr>
	</tbody>
</table>

imaging serotonergic fibers in the mouse spinal cord using the clarity/cubic technique

fibre lunghe che scendono verso il midollo spinale sono essenziali per la locomozione, percezione del dolore, e altri comportamenti. Il modello terminazione in fibra nel midollo spinale della maggior parte di questi sistemi in fibra non sono state esaminate a fondo in qualsiasi specie. fibre serotoninergici, che proiettano al midollo spinale, sono stati studiati nei ratti e opossum su sezioni istologiche e il loro significato funzionale è stata dedotta in base al loro modello di terminazione in fibra nel midollo spinale. Con lo sviluppo della chiarezza e tecniche cubica, è possibile studiare questo sistema di fibre e la sua distribuzione nel midollo spinale, che rischia di rivelare caratteristiche precedentemente sconosciuti di percorsi supraspinal serotoninergici. Qui, forniamo un protocollo dettagliato per l&#39;imaging delle fibre serotoninergici nel topo midollo spinale utilizzando la nitidezza, associato e le tecniche cubi. Il metodo prevede la perfusione di un mouse con una soluzione idrogel e chiarificazione del tessuto con una combinzione di compensazione reagenti. tessuto del midollo spinale è stato eliminato in poco meno di due settimane, e la conseguente colorazione immunofluorescenza contro la serotonina è stata completata in meno di dieci giorni. Con un microscopio a fluorescenza multi-fotone, il tessuto è stato digitalizzato e l&#39;immagine 3D è stata ricostruita utilizzando il software OsiriX.

Questa sezione mostra i risultati di anticorpi serotonina colorazione nel topo trasparente midollo spinale utilizzando una combinazione di chiarezza e protocolli cubi. Abbiamo dimostrato che le fibre serotoninergici sono presenti in tutti lamine del midollo spinale con una predominanza nella porzione ventrale del corno ventrale (Figura 1, vedi anche Video 1). Il tessuto di controllo non ha avuto fibre positive (risultato non è stato mostrato). Nel corno...

Watch this Scientific Journal Video about Imaging Serotonergic Fibers in the Mouse Spinal Cord Using the CLARITY/CUBIC Technique at JoVE.com

Imaging Serotonergic Fibers in the Mouse Spinal Cord Using the CLARITY/CUBIC Technique

Supraspinal projections are important for pain perception and other behaviors, and serotonergic fibers are one of these fiber systems. The present study focused on the application of the combined CLARITY/CUBIC protocol to the mouse spinal cord in order to investigate the termination of these serotonergic fibers.

Imaging Fibre serotoninergici nel midollo spinale mouse Uso del CHIAREZZA / Tecnica CUBIC

Long descending fibers to the spinal cord are essential for locomotion, pain perception, and other behaviors. The fiber termination pattern in the spinal ...

imaging-serotonergic-fibers-mouse-spinal-cord-using-claritycubic

Research

JoVE Journal

Neuroscience

10.4K Views.  Neuroscience Research Australia. Supraspinal projections are important for pain perception and other behaviors, and serotonergic fibers are one of these fiber systems. The present study focused on the application of the combined CLARITY/CUBIC protocol to the mouse spinal cord in order to investigate the termination of these serotonergic fibers.

Video: Imaging Serotonergic Fibers in the Mouse Spinal Cord Using the CLARITY/CUBIC Technique

Spinal Cord Electrophysiology II: Extracellular Suction Electrode Fabrication

Development of neural circuitries and locomotion can be studied using neonatal rodent spinal cord central pattern generator (CPG) behavior. We demonstrate a method to fabricate suction electrodes that are used to examine CPG activity, or fictive locomotion, in dissected rodent spinal cords. The rodent spinal cords are placed in artificial cerebrospinal fluid and the ventral roots are drawn into the suction electrode. The electrode is constructed by modifying a commercially available suction electrode. A heavier silver wire is used instead of the standard wire given by the commercially available electrode. The glass tip on the commercial electrode is replaced with a plastic tip for increased durability. We prepare hand drawn electrodes and electrodes made from specific sizes of tubing, allowing consistency and reproducibility. Data is collected using an amplifier and neurogram acquisition software. Recordings are performed on an air table within a Faraday cage to prevent mechanical and electrical interference, respectively.

A demonstration of the fabrication and use of an extracellular suction electrode used to measure electrophysiological recordings of neonatal rodent spinal cords in vitro

Spinal Cord Elettrofisiologia II: extracellulare fabbricazione di elettrodi di aspirazione

Development of neural circuitries and locomotion can be studied using neonatal rodent spinal cord central pattern generator (CPG) behavior. We demonstrate ...

Ricerca

Neuroscienze

In vivo Imaging of the Mouse Spinal Cord Using Two-photon Microscopy

In vivo imaging using two-photon microscopy 1 in mice that have been genetically engineered to express fluorescent proteins in specific cell types 2-3 has significantly broadened our knowledge of physiological and pathological processes in numerous tissues in vivo 4-7. In studies of the central nervous system (CNS), there has been a broad application of in vivo imaging in the brain, which has produced a plethora of novel and often unexpected findings about the behavior of cells such as neurons, astrocytes, microglia, under physiological or pathological conditions 8-17. However, mostly technical complications have limited the implementation of in vivo imaging in studies of the living mouse spinal cord. In particular, the anatomical proximity of the spinal cord to the lungs and heart generates significant movement artifact that makes imaging the living spinal cord a challenging task.
We developed a novel method that overcomes the inherent limitations of spinal cord imaging by stabilizing the spinal column, reducing respiratory-induced movements and thereby facilitating the use of two-photon microscopy to image the mouse spinal cord in vivo. This is achieved by combining a customized spinal stabilization device with a method of deep anesthesia, resulting in a significant reduction of respiratory-induced movements. This video protocol shows how to expose a small area of the living spinal cord that can be maintained under stable physiological conditions over extended periods of time by keeping tissue injury and bleeding to a minimum. Representative raw images acquired in vivo detail in high resolution the close relationship between microglia and the vasculature. A timelapse sequence shows the dynamic behavior of microglial processes in the living mouse spinal cord. Moreover, a continuous scan of the same z-frame demonstrates the outstanding stability that this method can achieve to generate stacks of images and/or timelapse movies that do not require image alignment post-acquisition. Finally, we show how this method can be used to revisit and reimage the same area of the spinal cord at later timepoints, allowing for longitudinal studies of ongoing physiological or pathological processes in vivo.

In vivo Imaging of the Mouse Spinal Cord Using Two-photon Microscopy

A minimally invasive protocol to stabilize the mouse spinal column and perform repetitive in vivo spinal cord imaging using two-photon microscopy is described. This method combines a spinal stabilization device and an anesthetic regimen to minimize respiratory-induced movements and produce raw imaging data that require no alignment or other post-processing.

Imaging in vivo del midollo spinale di topo Utilizzo di due fotoni Microscopia

In vivo imaging using two-photon microscopy 1 in mice that have been genetically engineered to express fluorescent proteins in specific cell types 2-3 has ...

Spinal Cord Transection in the Larval Zebrafish

Mammals fail in sensory and motor recovery following spinal cord injury due to lack of axonal regrowth below the level of injury as well as an inability to reinitiate spinal neurogenesis. However, some anamniotes including the zebrafish Danio rerio exhibit both sensory and functional recovery even after complete transection of the spinal cord. The adult zebrafish is an established model organism for studying regeneration following spinal cord injury, with sensory and motor recovery by 6&#160;weeks post-injury. To take advantage of in vivo analysis of the regenerative process available in the transparent larval zebrafish as well as genetic tools not accessible in the adult, we use the larval zebrafish to study regeneration after spinal cord transection. Here we demonstrate a method for reproducibly and verifiably transecting the larval spinal cord. After transection, our data shows sensory recovery beginning at 2&#160;days post-injury (dpi), with the C-bend movement detectable by 3 dpi and resumption of free swimming by 5 dpi. Thus we propose the larval zebrafish as a companion tool to the adult zebrafish for the study of recovery after spinal cord injury.

After spinal transection, adult zebrafish have functional recovery by six weeks post-injury. To take advantage of larval transparency and faster recovery, we present a method for transecting the larval spinal cord. After transection, we observe sensory recovery beginning at 2&#160;days post-injury, and C-bend movement by 3 days post-injury.

Spinal Cord transezione nel larvale Zebrafish

Mammals fail in sensory and motor recovery following spinal cord injury due to lack of axonal regrowth below the level of injury as well as an inability ...

A Procedure for Implanting a Spinal Chamber for Longitudinal In Vivo Imaging of the Mouse Spinal Cord

Studies in the mammalian neocortex have enabled unprecedented resolution of cortical structure, activity, and response to neurodegenerative insults by repeated, time-lapse in vivo imaging in live rodents. These studies were made possible by straightforward surgical procedures, which enabled optical access for a prolonged period of time without repeat surgical procedures. In contrast, analogous studies of the spinal cord have been previously limited to only a few imaging sessions, each of which required an invasive surgery. As previously described, we have developed a spinal chamber that enables continuous optical access for upwards of 8 weeks, preserves mechanical stability of the spinal column, is easily stabilized externally during imaging, and requires only a single surgery. Here, the design of the spinal chamber with its associated surgical implements is reviewed and the surgical procedure is demonstrated in detail. Briefly, this video will demonstrate the preparation of the surgical area and mouse for surgery, exposure of the spinal vertebra and appropriate tissue debridement, the delivery of the implant and vertebral clamping, the completion of the chamber, the removal of the delivery system, sealing of the skin, and finally, post-operative care. The procedure for chronic in vivo imaging using nonlinear microscopy will also be demonstrated. Finally, outcomes, limitations, typical variability, and a guide for troubleshooting are discussed.

A Procedure for Implanting a Spinal Chamber for Longitudinal In Vivo Imaging of the Mouse Spinal Cord

In this video, we describe a procedure for implanting a chronic optical imaging chamber over the dorsal spinal cord of a live mouse. The chamber, surgical procedure, and chronic imaging are reviewed and demonstrated.

Una procedura di impianto del Camera spinale per longitudinale<em&gt; In Vivo</em&gt; Imaging del cavo del mouse spinale

Studies in the mammalian neocortex have enabled unprecedented resolution of cortical structure, activity, and response to neurodegenerative insults by ...

Diffusion Imaging in the Rat Cervical Spinal Cord

Magnetic resonance imaging (MRI) is the state of the art approach for assessing the status of the spinal cord noninvasively, and can be used as a diagnostic and prognostic tool in cases of disease or injury. Diffusion weighted imaging (DWI), is sensitive to the thermal motion of water molecules and allows for inferences of tissue microstructure. This report describes a protocol to acquire and analyze DWI of the rat cervical spinal cord on a small-bore animal system. It demonstrates an imaging setup for the live anesthetized animal and recommends a DWI acquisition protocol for high-quality imaging, which includes stabilization of the cord and control of respiratory motion. Measurements with diffusion weighting along different directions and magnitudes (b-values) are used. Finally, several mathematical models of the resulting signal are used to derive maps of the diffusion processes within the spinal cord tissue that provide insight into the normal cord and can be used to monitor injury or disease processes noninvasively.

The goal of this protocol is to obtain high-quality diffusion weighted magnetic resonance imaging (DWI) of the rat spinal cord for noninvasive characterization of tissue microstructure. This protocol describes optimizations of the MRI sequence, radiofrequency coil, and analysis methods to enable DWI images free from artifacts.

Diffusion Imaging nel midollo spinale cervicale Rat

Magnetic resonance imaging (MRI) is the state of the art approach for assessing the status of the spinal cord noninvasively, and can be used as a ...

Two-photon Imaging of Cellular Dynamics in the Mouse Spinal Cord

Two-photon (2P) microscopy is utilized to reveal cellular dynamics and interactions deep within living, intact tissues. Here, we present a method for live-cell imaging in the murine spinal cord. This technique is uniquely suited to analyze neural precursor cell (NPC) dynamics following transplantation into spinal cords undergoing neuroinflammatory demyelinating disorders. NPCs migrate to sites of axonal damage, proliferate, differentiate into oligodendrocytes, and participate in direct remyelination. NPCs are thereby a promising therapeutic treatment to ameliorate chronic demyelinating diseases. Because transplanted NPCs migrate to the damaged areas on the ventral side of the spinal cord, traditional intravital 2P imaging is impossible, and only information on static interactions was previously available using histochemical staining approaches. Although this method was generated to image transplanted NPCs in the ventral spinal cord, it can be applied to numerous studies of transplanted and endogenous cells throughout the entire spinal cord. In this article, we demonstrate the preparation and imaging of a spinal cord with enhanced yellow fluorescent protein-expressing axons and enhanced green fluorescent protein-expressing transplanted NPCs.

A new ex vivo preparation for imaging the mouse spinal cord. This protocol allows for two-photon imaging of live cellular interactions throughout the spinal cord.

Due fotoni Imaging di Cellular Dynamics nel midollo spinale del mouse

Two-photon (2P) microscopy is utilized to reveal cellular dynamics and interactions deep within living, intact tissues. Here, we present a method for ...

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in adult mammalian animals remains elusive. In this study, we describe an experimental procedure for measuring calcium dynamics through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy. This method enables recordings and quantifications of neural activity in bilateral mouse brain regions one at a time in the same experiment for a prolonged period in vivo. Key aspects of this method, which can be completed within an hour, include minimally invasive surgery procedures for creating dual optical windows, and the use of 2P imaging. Although we only demonstrate the technique in the S1 area, the method can be applied to other regions of the living brain facilitating the elucidation of structural and functional complexities of brain neural networks.

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

We describe an experimental procedure for measuring neuronal activity through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy in vivo.

Imaging di attività neurale nella corteccia somatosensoriale primaria utilizzando Thy1-topi transgenici GCaMP6s

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in ...

Laminectomy and Spinal Cord Window Implantation in the Mouse

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated digital vaporizer is utilized to achieve a stable plane of anesthesia at a low-flow rate of isoflurane. A single vertebral spine is removed, and a commercially available cover-glass is overlaid on a thin agarose bed. A 3D-printed plastic backplate is then affixed to the adjacent vertebral spines using tissue adhesive and dental cement. A stabilization platform is used to reduce motion artifact from respiration and heartbeat. This rapid and clamp-free method is well-suited for acute multi-photon fluorescence microscopy. Representative data are included for an application of this technique to two-photon microscopy of the spinal cord vasculature in transgenic mice expressing eGFP:Claudin-5 &#8212; a tight junction protein.

This protocol describes implantation of a glass window onto the spinal cord of a mouse to facilitate visualization by intravital microscopy.

Laminectomia e impianto della finestra del cavo spinale nel mouse

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated ...

Diffusion Tensor Magnetic Resonance Imaging in Chronic Spinal Cord Compression

Chronic spinal cord compression is the most common cause of spinal cord impairment in patients with nontraumatic spinal cord damage. Conventional magnetic resonance imaging (MRI) plays an important role in both confirming the diagnosis and evaluating the degree of compression. However, the anatomical detail provided by conventional MRI is not sufficient to accurately estimate neuronal damage and/or assess the possibility of neuronal recovery in chronic spinal cord compression patients. In contrast, diffusion tensor imaging (DTI) can provide quantitative results according to the detection of water molecule diffusion in tissues. In the present study, we develop a methodological framework to illustrate the application of DTI in chronic spinal cord compression disease. DTI fractional anisotropy (FA), apparent diffusion coefficients (ADCs), and eigenvector values are useful for visualizing microstructural pathological changes in the spinal cord. Decreased FA and increases in ADCs and eigenvector values were observed in chronic spinal cord compression patients compared to healthy controls. DTI could help surgeons understand spinal cord injury severity and provide important information regarding prognosis and neural functional recovery. In conclusion, this protocol provides a sensitive, detailed, and noninvasive tool to evaluate spinal cord compression.

Here, we present a protocol for the application of diffusion tensor imaging parameters to evaluate spinal cord compression.

Imaging a risonanza magnetica con Tensor di diffusione nella compressione del midollo spinale cronico

Chronic spinal cord compression is the most common cause of spinal cord impairment in patients with nontraumatic spinal cord damage. Conventional magnetic ...

Intra-Arterial Delivery of Neural Stem Cells to the Rat and Mouse Brain: Application to Cerebral Ischemia

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to intracranial delivery, intra-arterial administration of NSCs is less invasive and produces a more diffuse distribution of NSCs within the brain parenchyma. Further, intra-arterial delivery allows the first-pass effect in the brain circulation, lessening the potential for trapping of cells in peripheral organs, such as liver and spleen, a complication associated with peripheral injections. Here, we detail the methodology, in both mice and rats, for delivery of NSCs through the common carotid artery (mouse) or external carotid artery (rat) to the ipsilateral hemisphere after an ischemic stroke. Using GFP-labeled NSCs, we illustrate the widespread distribution achieved throughout the rodent ipsilateral hemisphere at 1 d, 1 week and 4 weeks after postischemic delivery, with a higher density in or near the ischemic injury site. In addition to long-term survival, we show evidence of differentiation of GFP-labeled cells at 4 weeks. The intra-arterial delivery approach described here for NSCs can also be used for administration of therapeutic compounds, and thus has broad applicability to varied CNS injury and disease models across multiple species.

A method for delivering neural stem cells, adaptable for injecting solutions or suspensions, through the common carotid artery (mouse) or external carotid artery (rat) after ischemic stroke is reported. Injected cells are distributed broadly throughout the brain parenchyma and can be detected up to 30 d after delivery.

Consegna intra-arteriosa di cellule staminali neurali al cervello di ratto e topo: applicazione all'ischemia cerebrale

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to ...