Quest'opera è stata sostenuta dal Ministero della scienza e tecnologia garantisce a MOST104-2311-B-010-010-MY3, MOST106-2321-B-010-012, gli istituti di ricerca nazionali di salute concede vi-EX106-10429NI e il programma di centro di ricerca aree consigliati sovvenzione da il Ministero dell'istruzione attraverso Brain Research Center, National Yang-Ming University di Taiwan, e Postdoctoral Fellowship concede MOST106-2811-B-010-031 (S.-Y.C.), MOST105-2811-B-010-036 e MOST106-2811-B-010-030 (H.-Y.K.).

I protocolli degli animali descritti qui sono stati approvati dalla cura degli animali e uso comitati della National Yang-Ming University.
1. preparazione del supporto per cuccioli neonatali nell'apparato stereotassica
<ol><li>Rendere il vassoio testa: tagliare il fondo di una provetta da centrifuga da 1,5 mL (15 mm di lunghezza) nella forma che si adatta alla testa dei cuccioli neonatale rimuovendo 1/5 della parete del tubo.</li>
	<li>Una casella di punta della pipetta con la giusta dimensione che si adatta con il piedistallo dell'apparato stereotassiche e rimuovere il coperchio superiore. Apporre il vassoio testa preparato nel passaggio 1.1 e una cassetta di incorporamento di tessuto sulla base del vassoio di punta con adesivo hot-fusione. L'altezza della cassetta incorporamento del tessuto è di 7 mm, che viene utilizzato per supportare il pup collo e corpo in posizione di testa-fisso.</li>
	<li>Posto l'intero setup apparecchiature stereotassiche.</li>
</ol>2. preparazione di 30g iniezione aghi in acciaio inox
<ol><li>Aghi di siringhe 30g prepulizia immergendo in cloroformio per 3 giorni.</li>
	<li>Utilizzare pinze per lentamente e con cautela estrarre l'ago dal suo hub in polipropilene in una cappa chimica.</li>
	<li>Lavare gli aghi con etanolo assoluto per 20 min seguita da risciacqui di etanolo 70% per 3 × 10 minuti su un agitatore a 50 giri/min. Lasciare che l'aria di aghi asciugare e conservare gli aghi puliti in una scatola pulita a temperatura ambiente (TA) fino all'utilizzo.</li>
</ol>3. preparare un adattatore per tubo rame Microinjection
<ol><li>Collegare la siringa microliter di un ago per iniezione 30G con un tubo di polietilene PE10 (PE10 tubo). Preparare un adattatore per tubo (tubo PE20) polietilene PE20 per colmare l'inserimento dell'ago e la siringa di microliter. L'uso dell'adattatore è necessario, perché il diametro del tubo PE10 è molto più piccolo di quello dell'ago della siringa microliter 26G.</li>
	<li>Preparare la tubatura per microliter siringa: collegare l'ago per iniezione pre-pulito 30 G con 5 cm di tubo PE20 e sigillare la giunzione con colla istantanea. Questo adattatore della tubazione è riutilizzabile. Nota: Se l'ago della siringa di microiniezione è 30G, la preparazione (fase 3.1) e l'utilizzo (punto 3.3) di questo adattatore non è necessario.</li>
	<li>Collegare l'adattatore del tubo (preparata al punto 3.1) con una siringa di microlitro (10 µ l).</li>
	<li>Collegare un'estremità del tubo PE10 (non più di 60 cm) sull'ago 30g dell'adattatore tubo PE20. Montare un nuovo ago per iniezione 30G sull'altra estremità del tubo PE10.</li>
</ol>4. caricare il tubo di microiniezione con acqua distillata in autoclave, tintura e virus
<ol><li>Togliere lo stantuffo della siringa microliter. Utilizzare una siringa di 25G per caricare la siringa microliter e il suo tubo di PE connesso con acqua distillata in autoclave per eliminare l'aria dal tubo.</li>
	<li>Posizionare il pistone torna alla siringa microliter e spingere lo stantuffo fino a 2 µ l di acqua distillata rimane in canna. Non lasciare che il volume di acqua distillata diventano inferiore a 2 µ l.</li>
	<li>Montare con cura siringa microliter la pompa a siringa micro portata.</li>
	<li>Pipettare piccole quantità di colorante 0,1% veloce verde (preparato in soluzione fisiologica allo 0,9% e filtrato con filtro di 0,22 µm) e i liquidi di virus a un pezzo di parafilm.</li>
	<li>Prelevare una piccola quantità di aria per rendere visibile una bolla d'aria all'incrocio tra l'ago per iniezione 30g e PE10 tubo seguita da 0,7 µ l di filtrato verde veloce di carico nel tubo per verificare il flusso dei liquidi nelle tubazioni microiniezione.</li>
	<li>Ritirare un'altra piccola quantità di aria per rendere una bolla d'aria seconda seguita caricando i liquidi di virus nella tubazione microiniezione.</li>
	<li>Collegare e fissare l'ago per microiniezione 30g al braccio dell'apparecchiatura stereotassica.</li>
</ol>5. anestesia di topi neonatali di ipotermia
<ol><li>Collocare il cucciolo in un manicotto di guanto di lattice e immergerlo nel ghiaccio tritato fino al collo per 5 min.</li>
	<li>Un pizzico di piedi di pup con pinze per non assicurarsi che nessuna risposta di ritiro dei suoi piedi.</li>
	<li>Collocare il cucciolo con manica guanto di lattice nel vassoio di testa e metti del ghiaccio schiacciato attorno al manicotto in lattice per mantenere il freddo per anestesia di ipotermia.</li>
	<li>Applicare unguento veterinario sugli occhi del cucciolo per prevenire la secchezza mentre nell'ambito dell'anestesia se possibile.</li>
</ol>6. microiniezione
<ol><li>Preparare chirurgia sterile pulendo lo strumento stereotassica accuratamente con etanolo al 70%. Sterilizzare lo strumento chirurgico immergendole in etanolo al 70%.</li>
	<li>Strofinare la testa di pup con etanolo al 70%. Individuare la lambda pietra miliare sul cranio e contrassegnare la lambda con un pennarello. Dirigere la punta dell'ago per la lambda e impostare l'antero-posteriore (AP) e mediale-laterale (ML) Coordinate come zero.</li>
	<li>Spostare il braccio di iniezione al sito di destinazione, secondo le coordinate X e Y del sito di destinazione. Per il corpo striato di giorno postnatale (P) 2 cuccioli, le coordinate sono: AP, +2,4 mm in avanti facendo la lambda; ML, ± 1,0 mm laterale dalla linea mediana; dorso-ventrale (DV), −1.7 mm dal cranio. Segnare la posizione della tintura veloce verde in PE10 tubo con una penna.</li>
	<li>Portare giù l'ago per iniezione 30g lentamente a penetrare attraverso la pelle e il cranio e quindi portare la punta dell'ago finché non si ferma alla superficie del cranio. Impostare la coordinata DV come zero.</li>
	<li>Far cadere l'ago per iniezione 30g lentamente fino a raggiungere la coordinata DV del sito di destinazione. Attendere 1 minuto consentire il parenchima riprendendo la sua forma normale. Eseguire il programma di Microiniezione (100 nL/min).</li>
	<li>Assicurarsi che il marchio della tintura veloce verde si muove nel tubo PE affinché che il liquido di virus è iniettato nel cervello.</li>
	<li>Attendere 1 minuto dopo la cessazione della microiniezione e poi lentamente e progressivamente portare l'ago all'altezza di 1/2 di profondità DV entro 30 s. Dopo 30 s, estrarre lentamente l'ago dalla testa di pup.</li>
	<li>Ripetere il passaggio 6.2 a 6.7 finché non vengono completate le microiniezioni di tutti i siti mirati.</li>
</ol>7. post-chirurgica di recupero del cucciolo
<ol><li>Scaldare il pup per 20 min in un incubatore a 33 ° C. Controllare il recupero del cucciolo dall'ipotermia anestesia ogni 5 min fino a quando il cucciolo ha ripreso conoscenza sufficiente per mantenere decubito sternale.</li>
	<li>Riportare il cucciolo alla diga dopo il cucciolo è completamente recuperato.</li>
</ol>

<ol>
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Nello studio presente, dimostriamo un metodo semplice e affidabile stereotassica per iniettare il virus AAV nello striato del cervello di topo neonatale. Abbiamo microiniettati virus AAV-eGFP-Cre nello striato di topi reporter Ai14 a P2 e poi analizzata l'espressione del gene reporter presso P14. Abbiamo trovato che AAV trasdotte cellule GFP-positive in tutto il corpo striato a rostrocaudal livelli. Inoltre, quasi tutte le cellule GFP-positive co-espressi il gene reporter di tdTomato in cellule striatali, suggerendo una ...

Moderni studi sulla struttura e funzione del cervello di solito richiedono manipolazione genetica di specifici geni nelle cellule neuronali. Per sondare le funzioni dei geni differenti, topi transgenici portatori di alleli mutanti, tra cui knockout e knock-in alleli sono stati generati regolarmente. Chirurgia stereotassica cerebrale per roditori adulti è un metodo standard per fornire localmente farmaci, virus, traccianti e altri reagenti a specifiche regioni del cervello del roditore1,2. Applicando la chirurgia stereotassica cervello di topi transgenici permette di manipolare geneticamente la funzione del gene e l'attività neuronale in specifiche popolazioni neuronali del cervello del mouse. La manipolazione di specifici del tipo di cella fornisce un approccio potente per decifrare funzioni neuronali nei complessi circuiti neurali del cervello3,4,5.
Sviluppo neurale del sistema nervoso comincia alle prime fasi embrionali, e continuano i processi di sviluppo dopo la nascita fino al periodo giovanile. Postnatale maturazione del sistema nervoso include il cablaggio sinaptico preciso dei circuiti neurali, che è essenziale per le funzioni fisiologiche e cognitive del cervello6. Pertanto, è importante non solo per comprendere lo sviluppo neurale normale studiare eventi inerenti allo sviluppo che si verificano in finestre temporali neonatale, ma può anche fornire comprensioni nella patogenesi di neurodevelopmental ed i disordini neuropsichiatrici7 ,8. Sebbene i metodi di chirurgia stereotassica cerebrale per roditori adulti sono prontamente disponibili2,9, alcuni protocolli sono disponibili su internet per chirurgia stereotassica cerebrale in topi neonatali10,11. Infatti, microiniezioni stereotassiche dei reagenti nei cervelli dei cuccioli del mouse neonatale sono difficili, perché la testa di pup neonatale è troppo fragile per essere fissato nell'apparato stereotassica standard. Tuttavia, l'applicazione della chirurgia stereotassica cerebrale di topi transgenici è fattibile per topi neonatali12. Qui, descriviamo un metodo semplice con un setup fatti in casa per eseguire chirurgia stereotassica cerebrale nei cuccioli di neonato mouse. Dimostriamo che questa tecnica permette di eliminare condizionalmente floxed geni di microinjecting ricombinasi AAV-esprimendo Cre DNA nello striato di topi gene reporter e condizionalmente floxed topi transgenici. Questa tecnica è anche applicabile per fornire reagenti nello striato neonatale di topi wild-type.

<table border="0" cellpadding="0" cellspacing="0" width="1134">
	<tbody>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">30G PrecisionGlide Needle</td>
			<td style="width:273px;">Becton Dickinson</td>
			<td style="width:199px;">REF 305106</td>
			<td style="width:395px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Chloroform</td>
			<td style="width:273px;">JT Baker</td>
			<td style="width:199px;">9180-03</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Hamilton MICROLITER Syringe</td>
			<td style="width:273px;">Hamilton&#160;</td>
			<td style="width:199px;">80300</td>
			<td style="width:395px;">30G needle fit for PE10 tube; 26G needle needs a PE20 adaptor</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Polyethylene tubing PE20</td>
			<td style="width:273px;">Becton Dickinson</td>
			<td style="width:199px;">427406</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Polyethylene tubing PE10</td>
			<td style="width:273px;">Becton Dickinson</td>
			<td style="width:199px;">427401</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Micro Flow Rate Syringe Pump</td>
			<td style="width:273px;">Longer Precision Pump Co.</td>
			<td style="width:199px;">TJ-2A (Controller) and L0107-2A (Drive Unit)</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">25G syringe</td>
			<td style="width:273px;">Becton Dickinson</td>
			<td style="width:199px;">REF 302105</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Fast green</td>
			<td style="width:273px;">Sigma-Aldrich</td>
			<td style="width:199px;">F-7252</td>
			<td style="width:395px;">0.1%</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Standard Stereotaxic Instruments</td>
			<td style="width:273px;">RWD Life Science</td>
			<td style="width:199px;">68037</td>
			<td style="width:395px;">Without using 68030 Mouse/Neonatal Rat Adaptor</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Anti-FOXP2 antibody</td>
			<td style="width:273px;">Abcam</td>
			<td style="width:199px;">ab16046</td>
			<td style="width:395px;">Rabbit polyclonal to FOXP2, 1:4K</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Anti-RFP antibody</td>
			<td style="width:273px;">Abcam</td>
			<td style="width:199px;">ab65856</td>
			<td style="width:395px;">Mouse monoclonal to RFP, 1:1K</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">BX63 microscope</td>
			<td style="width:273px;">Olympus</td>
			<td style="width:199px;">BX63</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">LSM 880 confocal microscope</td>
			<td style="width:273px;">Zeiss</td>
			<td style="width:199px;">LSM 880</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Goat anti-rabbit conjugated Alexa fluor594</td>
			<td style="width:273px;">Jackson lmmunoReserch Laboratories Inc.</td>
			<td style="width:199px;">111-585-003</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">AAV9.hSynapsin.HI.eGFP-Cre.WPRE.SV40</td>
			<td style="width:273px;">Penn Vector Core</td>
			<td style="width:199px;">AV-9-PV1848</td>
			<td style="width:395px;">Lot # CS0987, 5.506x1013 (GC/mL)</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">AAV9.chicken actin-eGFP</td>
			<td style="width:273px;">AAV core, Institute of Biomedical Sciences, Academia Sinica, Taiwan</td>
			<td style="width:199px;">N/A</td>
			<td style="width:395px;">1x1014 (GC/ml)</td>
		</tr>
		<tr height="58">
			<td height="58" style="height:59px;width:269px;">B6.Cg-Gt(ROSA)26Sortm14(CAG-tdTomato)Hze/J</td>
			<td style="width:273px;">The Jackson Labtorary&#160;</td>
			<td style="width:199px;">007914</td>
			<td>Ai14</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">B6(Cg)-Foxp2tm1.1Sfis/CfreJ</td>
			<td style="width:273px;">The Jackson Labtorary&#160;</td>
			<td style="width:199px;">026259</td>
			<td style="width:395px;">Foxp2fl/fl</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:269px;">Dulbecco&#8217;s phosphate buffered saline</td>
			<td style="width:273px;">Corning&#160;cellgro</td>
			<td style="width:199px;">21-030-CVR</td>
			<td></td>
		</tr>
	</tbody>
</table>

stereotaxic surgery for genetic manipulation in striatal cells of neonatal mouse brains

Molti geni sono espressi nel cervello embrionale, e alcuni di loro sono continuamente espresso nel cervello dopo la nascita. Per tali geni espressi in modo persistente, possono funzionare per regolare il processo di sviluppo e/o funzione fisiologica nel cervello neonatale. Per indagare le funzioni neurobiologiche di specifici geni nel cervello, è essenziale che inattivano geni nel cervello. Qui, descriviamo un semplice metodo stereotassica per inattivare l'espressione genica nel corpo striato di topi transgenici alle finestre temporali neonatale. AAV-eGFP-Cre virus erano microiniettati nello striato di topi Ai14 reporter gene al giorno postnatale (P) 2 di chirurgia stereotassica cerebrale. L'espressione di gene reporter tdTomato è stata rilevata nello striatum P14, suggerendo che un successo Cre-loxP mediato ricombinazione del DNA in cellule trasdotte AAV striatali. Abbiamo validato ulteriormente questa tecnica da microinjecting virus AAV-eGFP-Cre nei topi P2Foxp2fl/fl . Doppia etichettatura di GFP e Foxp2 ha mostrato che le cellule GFP-positive mancavano immunoreactivity Foxp2 nello striatum P9, suggerendo la perdita della proteina Foxp2 in cellule striatali AAV-eGFP-Cre trasformata. Presi insieme, questi risultati dimostrano un'efficace eliminazione genetica da stereotassicamente iniettati virus AAV-eGFP-Cre in specifiche popolazioni neuronali nel cervello neonatale di topi transgenici floxed. In conclusione, la nostra tecnica stereotassica fornisce una piattaforma facile e semplice per manipolazione genetica in cervelli di topo neonatale. La tecnica non può essere utilizzata solo per eliminare geni in regioni specifiche del cervello neonatale, ma può essere utilizzato anche per iniettare droghe farmacologiche, traccianti neuronali, geneticamente optogenetica e proteine chemogenetics, indicatori di attività neuronale e altri reagenti nello striato del cervello neonatale del mouse.

Per il primo set di esperimento, abbiamo microiniettati 200 nL di AAV9.hSynapsin.HI.eGFP-Cre.WPRE.SV40 virus (AAV-eGFP-Cre, diluizione 1: 10 in soluzione salina tamponata con fosfato di Dulbecco) che esprimono la ricombinasi Cre DNA fusi con GFP in P2 striato di topi Ai14. I topi Ai14 rapidi tdTomato gene reporter all'omissione Cre-mediata di loxP-fiancheggiato (floxed) fermata cassetta (Figura 2F). I cervelli sono stati raccolti presso P14 per immunostaining...

Watch this Scientific Journal Video about Stereotaxic Surgery for Genetic Manipulation in Striatal Cells of Neonatal Mouse Brains at JoVE.com

Stereotaxic Surgery for Genetic Manipulation in Striatal Cells of Neonatal Mouse Brains

Chirurgia stereotassica per la manipolazione genetica in cellule striatali di cervelli di topo neonatale

Descriviamo un protocollo di chirurgia stereotassica con un dispositivo fisso testa fatti in casa per microinjecting reagenti nello striato del cervello neonatale del mouse. Questa tecnica permette la manipolazione genetica in cellule neuronali di specifiche regioni del cervello di topo neonatale.

Many genes are expressed in embryonic brains, and some of them are continuously expressed in the brain after birth. For such persistently expressed genes, ...

stereotaxic-surgery-for-genetic-manipulation-striatal-cells-neonatal

Research

JoVE Journal

Neuroscience

14.8K Views.  National Yang-Ming University. Descriviamo un protocollo di chirurgia stereotassica con un dispositivo fisso testa fatti in casa per microinjecting reagenti nello striato del cervello neonatale del mouse. Questa tecnica permette la manipolazione genetica in cellule neuronali di specifiche regioni del cervello di topo neonatale.

Video: Stereotaxic Surgery for Genetic Manipulation in Striatal Cells of Neonatal Mouse Brains

Rodent Stereotaxic Surgery and Animal Welfare Outcome Improvements for Behavioral Neuroscience

Stereotaxic surgery for the implantation of cannulae into specific brain regions has for many decades been a very successful experimental technique to investigate the effects of locally manipulated neurotransmitter and signaling pathways in awake, behaving animals. Moreover, the stereotaxic implantation of electrodes for electrophysiological stimulation and recording studies has been instrumental to our current understanding of neuroplasticity and brain networks in behaving animals. Ever-increasing knowledge about optimizing surgical techniques in rodents1-4, public awareness concerning animal welfare issues and stringent legislation (e.g., the 2010 European Union Directive on the use of laboratory animals5) prompted us to refine these surgical procedures, particularly with respect to implementing new procedures for oxygen supplementation and the continuous monitoring of blood oxygenation and heart rate levels during the surgery as well as introducing a standardized protocol for post-surgical care. Our observations indicate that these modifications resulted in an increased survival rate and an improvement in the general condition of the animals after surgery (e.g. less weight loss and a more active animal). This video presentation will show the general procedures involved in this type of stereotaxic surgery with special attention to our several modifications. We will illustrate these surgical procedures in rats, but it is also possible to perform this type of surgery in mice or other small laboratory animals by using special adaptors for the stereotaxic apparatus6.

Stereotaxic surgery on rodents allows for targeted administration of drugs or electrical stimulation and recordings in awake, behaving animals. In this video presentation we will demonstrate recent procedural refinements to this long-standing procedure that successfully improved survival rate and reduced post-surgical weight loss.

Chirurgia Stereotassica roditori e animali Miglioramenti Esito di assistenza sociale per Behavioral Neuroscience

Stereotaxic surgery for the implantation of cannulae into specific brain regions has for many decades been a very successful experimental technique to ...

Ricerca

Neuroscienze

Dissection and Culture of Mouse Dopaminergic and Striatal Explants in Three-Dimensional Collagen Matrix Assays

Midbrain dopamine (mdDA) neurons project via the medial forebrain bundle towards several areas in the telencephalon, including the striatum1. Reciprocally, medium spiny neurons in the striatum that give rise to the striatonigral (direct) pathway innervate the substantia nigra2. The development of these axon tracts is dependent upon the combinatorial actions of a plethora of axon growth and guidance cues including molecules that are released by neurites or by (intermediate) target regions3,4. These soluble factors can be studied in vitro by culturing mdDA and/or striatal explants in a collagen matrix which provides a three-dimensional substrate for the axons mimicking the extracellular environment. In addition, the collagen matrix allows for the formation of relatively stable gradients of proteins released by other explants or cells placed in the vicinity (e.g. see references 5 and 6). Here we describe methods for the purification of rat tail collagen, microdissection of dopaminergic and striatal explants, their culture in collagen gels and subsequent immunohistochemical and quantitative analysis. First, the brains of E14.5 mouse embryos are isolated and dopaminergic and striatal explants are microdissected. These explants are then (co)cultured in collagen gels on coverslips for 48 to 72 hours in vitro. Subsequently, axonal projections are visualized using neuronal markers (e.g. tyrosine hydroxylase, DARPP32, or &beta;III tubulin) and axon growth and attractive or repulsive axon responses are quantified. This neuronal preparation is a useful tool for in vitro studies of the cellular and molecular mechanisms of mesostriatal and striatonigral axon growth and guidance during development. Using this assay, it is also possible to assess other (intermediate) targets for dopaminergic and striatal axons or to test specific molecular cues.

Explants from the midbrain dopamine system and striatum are used in a collagen matrix assay for the in vitro analysis of mesostriatal and striatonigral pathway development. In this assay axonal outgrowth and guidance can be manipulated and quantified. It can also be modified for assessing other regions or molecular cues.

Dissezione e Cultura del mouse dopaminergici e striatali Espianti di saggi di collagene matrice tridimensionale

Midbrain dopamine (mdDA) neurons project via the medial forebrain bundle towards several areas in the telencephalon, including the striatum1. ...

Stereotaxic Surgery for Excitotoxic Lesion of Specific Brain Areas in the Adult Rat

Many behavioral functions in mammals, including rodents and humans, are mediated principally by discrete brain regions. A common method for discerning the function of various brain regions for behavior or other experimental outcomes is to implement a localized ablation of function. In humans, patient populations with localized brain lesions are often studied for deficits, in hopes of revealing the underlying function of the damaged area. In rodents, one can experimentally induce lesions of specific brain regions.
Lesion can be accomplished in several ways. Electrolytic lesions can cause localized damage but will damage a variety of cell types as well as traversing fibers from other brain regions that happen to be near the lesion site. Inducible genetic techniques using cell-type specific promoters may also enable site-specific targeting. These techniques are complex and not always practical depending on the target brain area. Excitotoxic lesion using stereotaxic surgery, by contrast, is one of the most reliable and practical methods of lesioning excitatory neurons without damaging local glial cells or traversing fibers.
Here, we present a protocol for stereotaxic infusion of the excitotoxin, N-methyl-D-aspartate (NMDA), into the basolateral amygdala complex. Using anatomical indications, we apply stereotaxic coordinates to determine the location of our target brain region and lower an injection needle in place just above the target. We then infuse our excitotoxin into the brain, resulting in excitotoxic death of nearby neurons. While our experimental subject of choice is a rat, the same methods can be applied to other mammals, with the appropriate adjustments in equipment and coordinates.
This method can be used on a variety of brain regions, including the basolateral amygdala1-6, other amygdala nuclei6, 7, hippocampus8, entorhinal cortex9 and prefrontal cortex10. It can also be used to infuse biological compounds such as viral vectors1, 11. The basic stereotaxic technique could also be adapted for implantation of more permanent osmotic pumps, allowing more prolonged exposure to a compound of interest.

Targeted ablation of specific brain region(s) by infusion of an excitotoxin using stereotaxic coordinates is described. This technique could also be adapted for infusion of other chemicals into the rat brain.

La chirurgia stereotassica della lesione eccitotossico di specifiche aree cerebrali nel ratto adulto

Many behavioral functions in mammals, including rodents and humans, are mediated principally by discrete brain regions. A common method for discerning the ...

Visualization and Genetic Manipulation of Dendrites and Spines in the Mouse Cerebral Cortex and Hippocampus using In utero Electroporation

In utero electroporation (IUE) has become a powerful technique to study the development of different regions of the embryonic nervous system 1-5. To date this tool has been widely used to study the regulation of cellular proliferation, differentiation and neuronal migration especially in the developing cerebral cortex 6-8. Here we detail our protocol to electroporate in utero the cerebral cortex and the hippocampus and provide evidence that this approach can be used to study dendrites and spines in these two cerebral regions.
Visualization and manipulation of neurons in primary cultures have contributed to a better understanding of the processes involved in dendrite, spine and synapse development. However neurons growing in vitro are not exposed to all the physiological cues that can affect dendrite and/or spine formation and maintenance during normal development. Our knowledge of dendrite and spine structures in vivo in wild-type or mutant mice comes mostly from observations using the Golgi-Cox method 9. However, Golgi staining is considered to be unpredictable. Indeed, groups of nerve cells and fiber tracts are labeled randomly, with particular areas often appearing completely stained while adjacent areas are devoid of staining. Recent studies have shown that IUE of fluorescent constructs represents an attractive alternative method to study dendrites, spines as well as synapses in mutant / wild-type mice 10-11 (Figure 1A). Moreover in comparison to the generation of mouse knockouts, IUE represents a rapid approach to perform gain and loss of function studies in specific population of cells during a specific time window. In addition, IUE has been successfully used with inducible gene expression or inducible RNAi approaches to refine the temporal control over the expression of a gene or shRNA 12. These advantages of IUE have thus opened new dimensions to study the effect of gene expression/suppression on dendrites and spines not only in specific cerebral structures (Figure 1B) but also at a specific time point of development (Figure 1C).
Finally, IUE provides a useful tool to identify functional interactions between genes involved in dendrite, spine and/or synapse development. Indeed, in contrast to other gene transfer methods such as virus, it is straightforward to combine multiple RNAi or transgenes in the same population of cells. 
In summary, IUE is a powerful method that has already contributed to the characterization of molecular mechanisms underlying brain function and disease and it should also be useful in the study of dendrites and spines.

Visualization and Genetic Manipulation of Dendrites and Spines in the Mouse Cerebral Cortex and Hippocampus using In utero Electroporation

This article describes in detail a protocol to electroporate in utero the cerebral cortex and the hippocampus at E14.5 in mice. We also show that this is a valuable method to study dendrites and spines in these two cerebral regions.

Visualizzazione e manipolazione genetica di dendriti e spine nella corteccia cerebrale e nell&#39;ippocampo mouse utilizzando<em&gt; In utero</em&gt; Elettroporazione

In utero electroporation (IUE) has become a powerful technique to study the development of different regions of the embryonic nervous system 1-5. To date ...

Stereotaxic Injection of a Viral Vector for Conditional Gene Manipulation in the Mouse Spinal Cord

Intraparenchymal injection of a viral vector enables conditional gene manipulation in distinct populations of neurons or particular regions of the central nervous system. We demonstrate a stereotaxic injection technique that allows targeted gene expression or silencing in the dorsal horn of the mouse spinal cord. The surgical procedure is brief. It requires laminectomy of a single vertebra, providing for quick recovery of the animal and unimpaired motility of the spine. Controlled injection of a small vector suspension volume at low speed and use of a microsyringe with beveled glass cannula minimize the tissue lesion. The local immune response to the vector depends on the intrinsic properties of the virus employed; in our experience, it is minor and short-lived when a recombinant adeno-associated virus is used. A reporter gene such as enhanced green fluorescent protein facilitates monitoring spatial distribution of the vector, and the efficacy and cellular specificity of the transfection.

Viral vectors allow for targeted gene manipulation. We demonstrate a method for conditional gene expression or ablation in the mouse spinal cord, using stereotaxic injection of a viral vector into the dorsal horn, a prominent site of synaptic contact between primary somatosensory afferents and neurons of the central nervous system.

Iniezione stereotassica di un vettore virale per la manipolazione del gene condizionale nel midollo spinale del mouse

Intraparenchymal injection of a viral vector enables conditional gene manipulation in distinct populations of neurons or particular regions of the central ...

Genetic Manipulation of the Mouse Developing Hypothalamus through In utero Electroporation

Genetic modification of specific regions of the developing mammalian brain is a very powerful experimental approach. However, generating novel mouse mutants is often frustratingly slow. It has been shown that access to the mouse brain developing in utero with reasonable post-operatory survival is possible. Still, results with this procedure have been reported almost exclusively for the most superficial and easily accessible part of the developing brain, i.e. the cortex. The thalamus, a narrower and more medial region, has proven more difficult to target. Transfection into deeper nuclei, especially those of the hypothalamus, is perhaps the most challenging and therefore very few results have been reported. Here we demonstrate a procedure to target the entire hypothalamic neuroepithelium or part of it (hypothalamic regions) for transfection through electroporation. The keys to our approach are longer narcosis times, injection in the third ventricle, and appropriate kind and positioning of the electrodes. Additionally, we show results of targeting and subsequent histological analysis of the most recessed hypothalamic nucleus, the mammillary body.

Genetic Manipulation of the Mouse Developing Hypothalamus through In utero Electroporation

Despite the functional and medical importance of the hypothalamus, in utero genetic manipulation of its development has rarely been attempted. We show a detailed procedure for in utero electroporation into the mouse hypothalamus and show representative results of total and partial (regional) hypothalamic transfection.

La manipolazione genetica del topo sviluppo dell&#39;ipotalamo attraverso<em&gt; In utero</em&gt; Elettroporazione

Genetic  modification of specific regions of the developing mammalian brain is a very  powerful experimental approach. However, generating novel mouse ...

Whole Mount Immunofluorescent Staining of the Neonatal Mouse Retina to Investigate Angiogenesis In vivo

Angiogenesis is the complex process of new blood vessel formation defined by the sprouting of new blood vessels from a pre-existing vessel network. Angiogenesis plays a key role not only in normal development of organs and tissues, but also in many diseases in which blood vessel formation is dysregulated, such as cancer, blindness and ischemic diseases. In adult life, blood vessels are generally quiescent so angiogenesis is an important target for novel drug development to try and regulate new vessel formation specifically in disease. In order to better understand angiogenesis and to develop appropriate strategies to regulate it, models are required that accurately reflect the different biological steps that are involved. The mouse neonatal retina provides an excellent model of angiogenesis because arteries, veins and capillaries develop to form a vascular plexus during the first week after birth. This model also has the advantage of having a two-dimensional (2D) structure making analysis straightforward compared with the complex 3D anatomy of other vascular networks. By analyzing the retinal vascular plexus at different times after birth, it is possible to observe the various stages of angiogenesis under the microscope. This article demonstrates a straightforward procedure for analyzing the vasculature of a mouse retina using fluorescent staining with isolectin and vascular specific antibodies.

Whole Mount Immunofluorescent Staining of the Neonatal Mouse Retina to Investigate Angiogenesis In vivo

The neonatal murine retina provides a well characterized physiological model of angiogenesis, which permits investigations of the roles of different genes or drugs that modulate angiogenesis in an in vivo context. Immunofluorescent staining to accurately visualize the vascular plexus is pivotal to the success of these types of studies.

Tutta Monte immunofluorescenza del mouse Retina neonatale per Indagare Angiogenesi<em&gt; In vivo</em

Angiogenesis  is the complex process of new blood vessel formation defined by the sprouting  of new blood vessels from a pre-existing vessel network. ...

Genetic Manipulation of Cerebellar Granule Neurons In Vitro and In Vivo to Study Neuronal Morphology and Migration

Developmental events in the brain including neuronal morphogenesis and migration are highly orchestrated processes. In vitro and in vivo analyses allow for an in-depth characterization to identify pathways involved in these events. Cerebellar granule neurons (CGNs) that are derived from the developing cerebellum are an ideal model system that allows for morphological analyses. Here, we describe a method of how to genetically manipulate CGNs and how to study axono- and dendritogenesis of individual neurons. With this method the effects of RNA interference, overexpression or small molecules can be compared to control neurons. In addition, the rodent cerebellar cortex is an easily accessible in vivo system owing to its predominant postnatal development. We also present an in vivo electroporation technique to genetically manipulate the developing cerebella and describe subsequent cerebellar analyses to assess neuronal morphology and migration.

Genetic Manipulation of Cerebellar Granule Neurons In Vitro and In Vivo to Study Neuronal Morphology and Migration

Neuronal morphogenesis and migration are crucial events underlying proper brain development. Here, we describe methods to genetically manipulate cultured cerebellar granule neurons and the developing cerebellum for the assessment of morphology and migratory characteristics of neurons.

Manipolazione genetica delle cerebellare granuli neuroni<em&gt; In Vitro</em&gt; E<em&gt; In Vivo</em&gt; Per studiare neuronale Morfologia e migrazione

Developmental events in the brain including neuronal morphogenesis and migration are highly orchestrated processes. In vitro and in vivo analyses allow ...

Intracerebroventricular Viral Injection of the Neonatal Mouse Brain for Persistent and Widespread Neuronal Transduction

With the pace of scientific advancement accelerating rapidly, new methods are needed for experimental neuroscience to quickly and easily manipulate gene expression in the mouse brain. Here we describe a technique first introduced by Passini and Wolfe for direct intracranial delivery of virally-encoded transgenes into the neonatal mouse brain. In its most basic form, the procedure requires only an ice bucket and a microliter syringe. However, the protocol can also be adapted for use with stereotaxic frames to improve consistency for researchers new to the technique. The method relies on the ability of adeno-associated virus (AAV) to move freely from the cerebral ventricles into the brain parenchyma while the ependymal lining is still immature during the first 12-24 hr after birth. Intraventricular injection of AAV at this age results in widespread transduction of neurons throughout the brain. Expression begins within days of injection and persists for the lifetime of the animal. Viral titer can be adjusted to control the density of transduced neurons, while co-expression of a fluorescent protein provides a vital label of transduced cells. With the rising availability of viral core facilities to provide both off-the-shelf, pre-packaged reagents and custom viral preparation, this approach offers a timely method for manipulating gene expression in the mouse brain that is fast, easy, and far less expensive than traditional germline engineering.

Here we demonstrate a technique for widespread neuronal transduction by intraventricular injection of adeno-associated virus into the neonatal mouse brain. This method provides a rapid and easy way to attain lifelong expression of virally-delivered transgenes.

Intracerebroventricular Iniezione virale del cervello neonatale mouse per persistente e diffusa trasduzione neuronale

With the pace of scientific advancement accelerating rapidly, new methods are needed for experimental neuroscience to quickly and easily manipulate gene ...

Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo

Structural changes in the retina are common manifestations of ophthalmic diseases. Optical coherence tomography (OCT) enables their identification in vivo&#8212;rapidly, repetitively, and at a high resolution. This protocol describes OCT imaging in the mouse retina as a powerful tool to study optic neuropathies (OPN). The OCT system is an interferometry-based, non-invasive alternative to common post mortem histological assays. It provides a fast and accurate assessment of retinal thickness, allowing the possibility to track changes, such as retinal thinning or thickening. We present the imaging process and analysis with the example of the Opa1delTTAG mouse line. Three types of scans are proposed, with two quantification methods: standard and homemade calipers. The latter is best for use on the peripapillary retina during radial scans; being more precise, is preferable for analyzing thinner structures. All approaches described here are designed for retinal ganglion cells (RGC) but are easily adaptable to other cell populations. In conclusion, OCT is efficient in mouse model phenotyping and has the potential to be used for the reliable evaluation of therapeutic interventions.

Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo

This manuscript describes a protocol for the in vivo imaging of the mouse retina with high-resolution spectral domain optical coherence tomography (SD-OCT). It focuses on retinal ganglion cells (RGC) in the peripapillary region, with several scanning and quantifying approaches described.

Tomografia a coerenza ottica: Imaging Mouse ganglionari cellule In Vivo

Structural changes in the retina are common manifestations of ophthalmic diseases. Optical coherence tomography (OCT) enables their identification in ...

Chirurgia stereotassica per la manipolazione genetica in cellule striatali di cervelli di topo neonatale

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Capitoli in questo video

Chirurgia Stereotassica roditori e animali Miglioramenti Esito di assistenza sociale per Behavioral Neuroscience

Dissezione e Cultura del mouse dopaminergici e striatali Espianti di saggi di collagene matrice tridimensionale

La chirurgia stereotassica della lesione eccitotossico di specifiche aree cerebrali nel ratto adulto

Visualizzazione e manipolazione genetica di dendriti e spine nella corteccia cerebrale e nell'ippocampo mouse utilizzando

Iniezione stereotassica di un vettore virale per la manipolazione del gene condizionale nel midollo spinale del mouse

La manipolazione genetica del topo sviluppo dell'ipotalamo attraverso

Tutta Monte immunofluorescenza del mouse Retina neonatale per Indagare Angiogenesi

Manipolazione genetica delle cerebellare granuli neuroni

Intracerebroventricular Iniezione virale del cervello neonatale mouse per persistente e diffusa trasduzione neuronale

Tomografia a coerenza ottica: Imaging Mouse ganglionari cellule In Vivo