Gli autori desiderano ringraziare il seguente: Dr. Giuseppe Bronzino, Dr. Khamis Abu-Hassaballah, signor RJ Austin-LaFrance, e la signora Jessica Koranda.

Questo protocollo è appropriato per i topi di 3 e 18 mesi di età e peso approssimativo corpo di 30-50 g). I topi possono essere ottenute presso il Jackson Laboratory (Bar Harbor, ME). Tutti i protocolli chirurgici e sperimentali sono stati approvati dalla cura degli animali ed uso commissione Trinity College ed erano in conformità con la guida NIH per la cura e l&#39;uso di animali da laboratorio. 1. Preparazione degli animali e procedure chirurgiche <ol><li> Preparare cocktail anestesia contenente ketamina (25 mg / ml), xilazina (2,5 mg / ml) e acepromazina (0,5 mg / ml). Iniettare 1 ml / kg di peso corporeo nel quadrante inferiore destro dell&#39;addome completata da iniezioni 0,2 ml / kg ogni 45 min successivamente mantenere una profondità stabile dell&#39;anestesia usando l&#39;ritiro riflesso pedale. </li><li> Preparare topo anestetizzato per la chirurgia con la rasatura del pelo sul suo cranio con un rasoio elettrico. L&#39;area rasata dovrebbe includere mezzo degli occhi per mezzo delle orecchie. Assicurarsi di non radersi la whiskers in quanto fanno parte del sistema sensoriale barile del mouse. </li><li> Usare tamponi di cotone per applicare alcool isopropilico seguita da Betadine alla zona rasata sulla testa. Quindi, anche utilizzando tamponi di cotone, applicare una piccola quantità di olio minerale sugli occhi per evitare i bulbi oculari di asciugatura. </li><li> Utilizzare infantili polsini ratto orecchio invece di barre orecchio regolari per montare la testa dell&#39;animale sull&#39;apparato telaio stereotassico. Per fare questo, prima montare l&#39;orecchio sinistro sul polsino dell&#39;orecchio sinistro. Poi facilitare delicatamente l&#39;orecchio destro sulla cuffia destra appoggiando delicatamente la testa dell&#39;animale con una mano e portare avanti il ​​polsino dell&#39;orecchio con l&#39;altra mano. Quindi, posizionare una piastra elettrica sotto il corpo dell&#39;animale e impostarlo a 86 ° F a mantenere la temperatura corporea. </li><li> Quindi, verificare la presenza di rigidità bilaterale tentando di muovere la testa da un lato. L&#39;animale è correttamente montato sul telaio stereotassico quando la testa è rigido e non può essere spostata lateralmente ma può facilmente ruotare su e giù. </li><li> Riposare delicatamente ilmuso del mouse sulla barra del naso / dente assemblaggio assicurandosi che gli incisivi siano appoggiati delicatamente ma saldamente dentro l&#39;apertura dente della barra naso / dente. </li><li> Usando un bisturi sterile, praticare un&#39;incisione mediana partire dalla metà degli occhi per mezzo delle orecchie. Assicurarsi che il bisturi sia essere tenuto ad un angolo di 45 ° e applicare una pressione sufficiente a tagliare la fascia sottostante, ma non attraverso il cranio come che causare sanguinamento eccessivo. </li><li> Usare tamponi di cotone per separare la fascia ed esporre il cranio. Skull attrazioni bregma e lambda deve essere chiaramente visibile (Figura 1A). Assicurarsi che l&#39;animale è in posizione cranio piatto regolando la barra naso / dente tale che bregma e lambda punti di riferimento sono allo stesso la dorsoventral posizione (DV) (+0,1 mm). </li><li> Applicare una piccola quantità di soluzione fisiologica sterile per l&#39;area esposta e utilizzare tamponi di cotone per pulire delicatamente il cranio. Poi aspettare 2-3 minuti per il cranio completamente aria seccaprima di procedere. </li><li> Montare un ago sul braccio stereotassico sinistra per misurare la posizione di DV bregma e lambda. Il posizionamento DV di questi due punti di riferimento dovrebbe essere di 0,1 mm tra loro. In caso contrario, la barra naso del telaio stereotassico può essere regolata su e giù per raggiungere questo obiettivo. </li><li> Posizionare l&#39;ago sulla bregma per registrare il suo antero-posteriore (AP), laterale (LAT) e dorsoventrale (DV) misurazioni. Assicurarsi che l&#39;ago tocchi appena il cranio e non penetra esso. </li><li> Utilizzare un mouse atlante del cervello, come ad esempio &quot;The Brain Mouse in Stereotassica Coordinate&quot; 1, per determinare le coordinate per le strutture di destinazione: mediale via perforante (MPP) in bundle angolare e giro dentato (DG) dell&#39;ippocampo, relativo alla lambda e bregma, rispettivamente (vedi anche tabella 1). Quindi, utilizzare una penna a punta fine o una matita per segnare questi punti sul cranio. </li><li> Inoltre, segnare altri due punti sul lato controlaterale del cranio. Questi punti which servirà da terra (GND) e di riferimento (REF) dovrebbe essere circa 3 mm dalla linea mediana e posizionato longitudinalmente rispetto all&#39;altro (Figura 1A, anche Tabella 1). </li><li> Rimuovere il marcatore ago dal braccio stereotassico sinistra e sostituirlo con un trapano dentale elettrico dotato di un supporto stereotassico. Posizionare il trapano sopra ogni punto segnato e fare piccoli fori radica di circa 0,5 mm di diametro. Quando foratura, utilizzare un movimento su e giù ripetitivo e controllare frequentemente se il trapano è penetrato il cranio per esporre la superficie del cervello. </li><li> Delicatamente ma con fermezza guidare un elettrodo vite (# 0-80 1/8 in macchina viti in acciaio inox, intaglio cilindrica testa) in ciascuno dei fori controlaterale (GND e REF) in modo tale che esse tocchino appena la superficie corticale senza penetrare (Figura 1A ). Questi due elettrodi a vite fungono da terra e di riferimento. </li><li> Mount stimolanti e registrazione elettrodi in elettrode titolari sulla sinistra e braccio destro stereotassica, rispettivamente. </li><li> Collegare i terminali degli elettrodi stimolanti ad uno stimolatore elettrofisiologico con attuale isolamento e il terminale di elettrodo di registrazione di un amplificatore differenziale elettrofisiologico (guadagno = 1.000, filtro passabanda = 1 Hz-3 kHz) e poi ad un oscilloscopio digitale per l&#39;ispezione visiva di risposte evocate. Inoltre, collegare GND e terminali di elettrodo REF all&#39;amplificatore differenziale. </li><li> Delicatamente e lentamente inferiore stimolante ed elettrodi di registrazione con incrementi di 0,5 millimetri, mentre il monitoraggio visivamente la risposta evocata ad uno shock stimolo di 600-800 uA. Continuare ad abbassare ciascun elettrodo fino alla loro rispettiva posizione DV obiettivo e un segnale stereotipo si osserva l&#39;oscilloscopio (Figura 1B). </li><li> In seguito, utilizzare cemento acrilico dentale per fare un tappo per contenere i terminali degli elettrodi in luogo, qualsiasi cemento dentale che tocca la pelle deve essere cancellatoimmediatamente. Una volta che il cemento dentale è completamente guarito trasferire l&#39;animale dal telaio stereotassico ad una gabbia roditori pulito. Utilizzare una lampada riscaldante o pad per mantenere la temperatura interna. </li><li> Monitorare l&#39;animale ogni ora fino a quando non riprende conoscenza. Un&#39;iniezione di flunixin può essere somministrato come analgesico. </li></ol> 2. LTP induzione <ol><li> Permettere all&#39;animale 5-7 giorni per recuperare da un intervento chirurgico. Posto l&#39;animale in ambiente di registrazione costituito da una gabbia di Faraday (122 centimetri x 43 centimetri x 43 cm) dotato di materiale fonoassorbente e un commutatore rotante 5-canale che collega l&#39;elettrodo porta alla configurazione stimolante / registrazione. </li><li> Lasciare che l&#39;animale si adatti per 1-2 ore in ambiente di registrazione prima di collegare gli elettrodi agli strumenti stimolanti e registrazione (fare riferimento al punto 1.17). </li><li> Impostare i controlli stimolatore di uscita 400 uA e registrare l&#39;ampiezza di una media del 10 evocato risposte assicurandosi thad almeno 10 sec trascorrere tra stimoli. Utilizzare il metodo illustrato nella Figura 1C per quantificare la risposta evocata. Ripetere questa procedura per 600, 800, 1.000, 1.200, e 1.400 uA. </li><li> Costruire una curva di ingresso / uscita riportando l&#39;ampiezza media della risposta evocata contro intensità dello stimolo. Da questo grafico determinare l&#39;intensità dello stimolo che corrisponde al 50% dell&#39;ampiezza massima misurata. Utilizzare l&#39;intensità del 50% per il resto dell&#39;esperimento. </li><li> Poi, usando l&#39;intensità dello stimolo 50%, ottenere una linea di base registrando l&#39;ampiezza media di 5 risposte evocate ogni minuto per 15 min. Anche in questo caso assicurarsi che almeno 10 sec trascorrere tra stimoli. </li><li> Successivamente consegnare la stimolazione tetanica composta da 10 raffiche di 10 impulsi erogati a 400 Hz con una velocità di raffica di 5 Hz per la via perforante mediale. Monitorare l&#39;animale attentamente per i segni di sequestro, tra cui frullati di cane bagnato. Se l&#39;animale ha un sequestro della speriment deve essere chiuso e tutti i dati da tale animale deve essere escluso dai risultati dello studio. </li><li> Quindi, continuare a registrare l&#39;ampiezza media di 5 risposte evocate ogni minuto per 30 minuti posttetanization. Dopo di che, confrontare questa ampiezza all&#39;ampiezza basale ottenuto nella fase 2.5 calcolando la variazione percentuale rispetto al basale (Figura 2). </li><li> A seguito della conclusione degli esperimenti, l&#39;animale è eutanasia mediante inalazione di isoflurane, un metodo che è coerente con gli orientamenti in materia di eutanasia della American Veterinary Medical Association. </li></ol>

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	<li>Paxinos, G., Franklin, K. B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The mouse brain in stereotaxic coordinates. , (2004).</li><li>Bliss, T. V. P., Lomo, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-lasting+potentiation+of+synaptic+transmission+in+the+dentate+area+of+the+anesthetized+rabbit+following+stimulation+of+the+perforant+path.">Long-lasting potentiation of synaptic transmission in the dentate area of the anesthetized rabbit following stimulation of the perforant path.</a> J. Physiol. 232, 331-356 (1973).</li><li>Blaise, J. H., Bronzino, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+stimulus+frequency+and+age+on+bidirectional+synaptic+plasticity+in+the+dentate+gyrus+of+freely+moving+rats.">Effects of stimulus frequency and age on bidirectional synaptic plasticity in the dentate gyrus of freely moving rats.</a> Exp. Neurol. 182, 497-506 (2003).</li><li>Blaise, J. H., Koranda, J. L., Chow, U., Haines, K. E., Dorward, E. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neonatal+isolation+stress+alters+bidirectional+long-term+synaptic+plasticity+in+amygdalo-hippocampal+synapses+in+freely+behaving+adult+rats.">Neonatal isolation stress alters bidirectional long-term synaptic plasticity in amygdalo-hippocampal synapses in freely behaving adult rats.</a> Brain Res. 1193, 25-33 (2008).</li><li>Koranda, J. L., Masino, S. A., Blaise, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bidirectional+synaptic+plasticity+in+the+dentate+gyrus+of+the+awake+freely+behaving+mouse.">Bidirectional synaptic plasticity in the dentate gyrus of the awake freely behaving mouse.</a> J. Neurosci. Methods. 167, 160-166 (2008).</li><li>Cooke, S. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autophosphorylation+of+alphaCaMKII+is+not+a+general+requirement+for+NMDA+receptor-dependent+LTP+in+the+adult+mouse.">Autophosphorylation of alphaCaMKII is not a general requirement for NMDA receptor-dependent LTP in the adult mouse.</a> J. Physiol. 574, 805-818 (2006).</li><li>Davis, S., Bliss, T. V., Dutrieux, G., Laroche, S., Errington, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+and+duration+of+long-term+potentiation+in+the+hippocampus+of+the+freely+moving+mouse.">Induction and duration of long-term potentiation in the hippocampus of the freely moving mouse.</a> J. Neurosci. Methods. 75, 75-80 (1997).</li><li>Jones, M. W., Peckham, H. M., Errington, M. L., Bliss, T. V., Routtenberg, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synaptic+plasticity+in+the+hippocampus+of+awake+C57BL/6+and+DBA/2+mice:+interstrain+differences+and+parallels+with+behavior.">Synaptic plasticity in the hippocampus of awake C57BL/6 and DBA/2 mice: interstrain differences and parallels with behavior.</a> Hippocampus. 11, 391-396 (2001).</li><li>Zhang, T. A., Tang, J., Pidoplichko, V. I., Dani, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Addictive+nicotine+alters+local+circuit+inhibition+during+the+induction+of+in+vivo+hippocampal+synaptic+potentiation.">Addictive nicotine alters local circuit inhibition during the induction of in vivo hippocampal synaptic potentiation.</a> J. Neurosci. 30, 6443-6453 (2010).</li><li>Tang, J., Dani, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dopamine+enables+in+vivo+synaptic+plasticity+associated+with+the+addictive+drug+nicotine.">Dopamine enables in vivo synaptic plasticity associated with the addictive drug nicotine.</a> Neuron. 63, 673-682 (2009).</li></ol>

Gli autori non hanno nulla da rivelare.

In questo protocollo, abbiamo dimostrato un metodo affidabile e semplice per lo studio LTP in DG nei topi banche si comportano. Mentre molti studi di LTP in ratti svegli sono stati effettuati 3,4, pochissimi sono stati condotti in topi svegli dovuto principalmente alla complessità tecnica rappresentata dalla limitata cranica immobiliare in topi e il peso di headstages elettrodi relativi al peso medio di 5 topi. I pochi studi che hanno dimostrato LTP in DG in banche comportarsi topi utilizzati sia ...

Lo sviluppo della tecnologia per manipolare i geni ha prodotto transgenici e knockout modelli murini di quasi tutte le malattie neurodegenerative e neurologiche. Ciò ha reso necessaria definizione di tecniche di ricerca elettrofisiologiche precedentemente utilizzati nelle più grandi specie di roditori al modello animale del mouse. Una di queste tecniche di indagine neurofisiologica è l&#39;uso potenziamento a lungo termine (LTP) per testare l&#39;efficacia di connessioni sinaptiche all&#39;interno delle reti neuronali coinvolti in vari disturbi neuropatologici. Questo protocollo descrive le tecniche per affidabile indagine elettrofisiologica della LTP in banche comportarsi topi. Il vantaggio di questo protocollo sugli altri è che è semplice e facile da implementare, ma è anche piuttosto meno costoso in quanto non richiede né l&#39;uso di costosi sistemi microdrive controllati dal computer nè effetto campo headstages transistor e, a nostra conoscenza, è il primo protocollo video di registrazioni elettrofisiologiche croniche to studiare LTP in banche comportarsi topi. A tal fine, descriviamo in questo articolo metodologie semplici per studiare potenziamento a lungo termine in topi banche si comportano. Queste metodologie possono essere facilmente tradotti in modelli murini transgenici e knockout di disturbi neuropatologici.

<table border="0" cellpadding="0" cellspacing="0" width="514">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Ketamine (100 mg/ml)</td>
			<td style="width:104px;">Henry Schein</td>
			<td style="width:137px;">10177</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Xylazine (20 mg/ml)</td>
			<td style="width:104px;">Henry Schein</td>
			<td style="width:137px;">33197</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Acepromazine (10 mg/ml)</td>
			<td style="width:104px;">Henry Schein</td>
			<td style="width:137px;">2177</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Dental acrylic powder</td>
			<td style="width:104px;">Lang Dental Manufacturing Co.</td>
			<td style="width:137px;">1330CLR</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Dental acrylic liquid</td>
			<td style="width:104px;">Lang Dental Manufacturing Co.</td>
			<td style="width:137px;">1306CLR</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Tungsten wire (0.127 mm)</td>
			<td style="width:104px;">World Precision Instruments</td>
			<td style="width:137px;">TGW0515</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Stainless Steel Hypodermic Tubing (0.286 mm)</td>
			<td style="width:104px;">World Precision Instruments</td>
			<td style="width:137px;">832400</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Flunixin (50 mg/ml)</td>
			<td style="width:104px;">Henry Schein</td>
			<td style="width:137px;">14165</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Epoxilyte</td>
			<td style="width:104px;">Superior Essex</td>
			<td style="width:137px;">EP 6001-M</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Stainless steel wire insert (0.2 mm)</td>
			<td style="width:104px;">World Precision Instruments</td>
			<td>792900</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:195px;">Stereotaxic frame apparatus</td>
			<td style="width:95px;">Kopf Instruments</td>
			<td style="width:137px;">Model 902</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:195px;">Ear cuffs (ear cups)</td>
			<td style="width:95px;">Kopf Instruments</td>
			<td style="width:137px;">Model 921&#160;</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:195px;">Electrophysiological stimulator</td>
			<td style="width:95px;">Astro-Med, Inc.</td>
			<td style="width:137px;">S88</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:195px;">Digital oscilloscope</td>
			<td style="width:95px;">B &#38; K Precision Corp.</td>
			<td style="width:137px;">2542</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:195px;">Current isolation unit</td>
			<td style="width:95px;">Astro-Med, Inc.</td>
			<td style="width:137px;">PSIU-6</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:195px;">Differential amplifier</td>
			<td style="width:95px;">World Precision Instruments, Inc.</td>
			<td style="width:137px;">DAM-50</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Commutator</td>
			<td style="width:95px;">Plastics One</td>
			<td style="width:137px;">SLC6</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:195px;">Dental drill</td>
			<td style="width:95px;">Stoelting</td>
			<td style="width:137px;">58650</td>
			<td style="width:79px;"></td>
		</tr>
	</tbody>
</table>

long-term potentiation of perforant pathway-dentate gyrus synapse in freely behaving mice

Studi di potenziamento a lungo termine dell&#39;efficacia sinaptica, un fenomeno sinaptica attività-dipendente avente proprietà che lo rendono interessante come potenziale meccanismo cellulare sottostante apprendimento e di memorizzazione, sono da tempo utilizzati per chiarire la fisiologia dei vari circuiti neuronali nell&#39;ippocampo, amigdala , e altre strutture limbiche e corticali. Con questo in mente, modelli transgenici murini di malattie neurologiche rappresentano piattaforme utili per condurre potenziamento a lungo termine (LTP) studi per sviluppare una maggiore comprensione del ruolo dei geni nella comunicazione sinaptica normale e anormale nelle reti neuronali coinvolti nell&#39;apprendimento, emozioni e informazioni trasformazione. Questo articolo descrive metodologie di affidabilità indurre LTP nel topo liberamente comportarsi. Queste metodologie possono essere utilizzate in studi di transgenici e knockout banche comportarsi modelli murini di malattie neurodegenerative.

La tabella 1 mostra le coordinate per la DG e mpp fini del presente protocollo figura 1A mostra i contrassegni per le strutture di destinazione sul cranio.. Mostrato anche sono la posizione degli elettrodi di terra e di riferimento Figura 1B illustra rappresentante risposta evocata traccia sia pre- e posttetanization nello stesso animale. Si noti che il posttetanization risposta evocata è maggiore della risposta pretetanization che è indicativo di LTP induzione 2...

Watch this Scientific Journal Video about Long-term Potentiation of Perforant Pathway-dentate Gyrus Synapse in Freely Behaving Mice at JoVE.com

Long-term Potentiation of Perforant Pathway-dentate Gyrus Synapse in Freely Behaving Mice

Transgenici e knockout modelli murini di malattie neurologiche sono utili per studiare il ruolo dei geni in neurofisiologia normale e anormale. Questo articolo descrive metodologie che possono essere utilizzati per studiare potenziamento a lungo termine, un meccanismo cellulare che può essere alla base dell&#39;apprendimento e della memoria, in transgenici e knockout banche comportarsi modelli murini di neuropatologia.

Potenziamento a lungo termine di perforant Pathway-giro dentato Synapse in Liberamente Comportarsi Mice

Studies of long-term potentiation of synaptic efficacy, an activity-dependent synaptic phenomenon having properties that make it attractive as a potential ...

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14.0K Views.  Trinity College.  Transgenici e knockout modelli murini di malattie neurologiche sono utili per studiare il ruolo dei geni in neurofisiologia normale e anormale. Questo articolo descrive metodologie che possono essere utilizzati per studiare potenziamento a lungo termine, un meccanismo cellulare che può essere alla base dell'apprendimento e della memoria, in transgenici e knockout banche comportarsi modelli murini di neuropatologia. 

Video: Long-term Potentiation of Perforant Pathway-dentate Gyrus Synapse in Freely Behaving Mice

Mouse Short- and Long-term Locomotor Activity Analyzed by Video Tracking Software

Locomotor activity (LMA) is a simple and easily performed measurement of behavior in mice and other rodents. Improvements in video tracking software (VTS) have allowed it to be coupled to LMA testing, dramatically improving specificity and sensitivity when compared to the line crossings method with manual scoring. In addition, VTS enables high-throughput experimentation. While similar to automated video tracking used for the open field test (OFT), LMA testing is unique in that it allows mice to remain in their home cage and does not utilize the anxiogenic stimulus of bright lighting during the active phase of the light-dark cycle. Traditionally, LMA has been used for short periods of time (mins), while longer movement studies (hrs-days) have often used implanted transmitters and biotelemetry. With the option of real-time tracking, long-, like short-term LMA testing, can now be conducted using videography. Long-term LMA testing requires a specialized, but easily constructed, cage so that food and water (which is usually positioned on the cage top) does not obstruct videography. Importantly, videography and VTS allows for the quantification of parameters, such as path of mouse movement, that are difficult or unfeasible to measure with line crossing and/or biotelemetry. In sum, LMA testing coupled to VTS affords a more complete description of mouse movement and the ability to examine locomotion over an extended period of time.

Locomotor activity (LMA) is a simple and easily performed measurement of behavior in mice. Coupling of video tracking software (VTS) and LMA allows for the improvement of specificity and sensitivity, especially when compared with the manual, line crossing method of LMA analysis. Additionally VTS allows long-term tracking of mouse LMA.

Mouse a breve e lungo termine di attività locomotoria analizzati da Tracking Software Video

Locomotor  activity (LMA) is a simple and easily performed measurement of behavior in mice  and other rodents. Improvements in video tracking software ...

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Construction of Microdrive Arrays for Chronic Neural Recordings in Awake Behaving Mice

State-of-the-art electrophysiological recordings from the brains of freely behaving animals allow researchers to simultaneously examine local field potentials (LFPs) from populations of neurons and action potentials from individual cells, as the animal engages in experimentally relevant tasks. Chronically implanted microdrives allow for brain recordings to last over periods of several weeks. Miniaturized drives and lightweight components allow for these long-term recordings to occur in small mammals, such as mice. By using tetrodes, which consist of tightly braided bundles of four electrodes in which each wire has a diameter of 12.5 &mu;m, it is possible to isolate physiologically active neurons in superficial brain regions such as the cerebral cortex, dorsal hippocampus, and subiculum, as well as deeper regions such as the striatum and the amygdala. Moreover, this technique insures stable, high-fidelity neural recordings as the animal is challenged with a variety of behavioral tasks. This manuscript describes several techniques that have been optimized to record from the mouse brain. First, we show how to fabricate tetrodes, load them into driveable tubes, and gold-plate their tips in order to reduce their impedance from M&Omega; to K&Omega; range. Second, we show how to construct a custom microdrive assembly for carrying and moving the tetrodes vertically, with the use of inexpensive materials. Third, we show the steps for assembling a commercially available microdrive (Neuralynx VersaDrive) that is designed to carry independently movable tetrodes. Finally, we present representative results of local field potentials and single-unit signals obtained in the dorsal subiculum of mice. These techniques can be easily modified to accommodate different types of electrode arrays and recording schemes in the mouse brain.

The design and assembly of microdrives for in vivo electrophysiological recordings of brain signals from the mouse is described. By attaching microelectrode bundles to sturdy driveable carriers, these techniques allow for long-term and stable neural recordings. The lightweight design allows for unrestricted behavioral performance by the animal following drive implantation.

Costruzione di matrici Microdrive per cronici Recordings neurali in topi Comportarsi Awake

State-of-the-art electrophysiological recordings from the brains of freely behaving animals allow researchers to simultaneously examine local field ...

Trace Fear Conditioning in Mice

In this experiment we present a technique to measure learning and memory. In the trace fear conditioning protocol presented here there are five pairings between a neutral stimulus and an unconditioned stimulus. There is a 20 sec trace period that separates each conditioning trial. On the following day freezing is measured during presentation of the conditioned stimulus (CS) and trace period. On the third day there is an 8 min test to measure contextual memory. The representative results are from mice that were presented with the aversive unconditioned stimulus (shock) compared to mice that received the tone presentations without the unconditioned stimulus. Trace fear conditioning has been successfully used to detect subtle learning and memory deficits and enhancements in mice that are not found with other fear conditioning methods. This type of fear conditioning is believed to be dependent upon connections between the medial prefrontal cortex and the hippocampus. One current controversy is whether this method is believed to be amygdala-independent. Therefore, other fear conditioning testing is needed to examine amygdala-dependent learning and memory effects, such as through the delay fear conditioning.

In the following experiment we describe a protocol for trace fear conditioning in mice. This type of associative memory includes a trace period that separates the neutral stimulus and the unconditioned stimulus.

Trace paura condizionata in topi

In this experiment we present a technique to measure learning and memory. In the trace fear conditioning protocol presented here there are five pairings ...

The Modified Hole Board - Measuring Behavior, Cognition and Social Interaction in Mice and Rats

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure multiple dimensions of unconditioned behavior in small laboratory mammals (e.g., mice, rats, tree shrews and small primates). This paradigm is a valuable alternative for the use of a behavioral test battery, since a broad behavioral spectrum of an animal&#8217;s behavioral profile can be investigated in one single test.
The apparatus consists of a box, representing the &#8216;protected&#8217; area, separated from a group compartment. A board, on which small cylinders are staggered in three lines, is placed in the center of the box, representing the &#8216;unprotected&#8217; area of the set-up. The cognitive abilities of the animals can be measured by baiting some cylinders on the board and measuring the working and reference memory. Other unconditioned behavior, such as activity-related-, anxiety-related- and social behavior, can be observed using this paradigm. Behavioral flexibility and the ability to habituate to a novel environment can additionally be observed by subjecting the animals to multiple trials in the mHB, revealing insight into the animals&#8217; adaptive capacities.
Due to testing order effects in a behavioral test battery, na&#239;ve animals should be used for each individual experiment. By testing multiple behavioral dimensions in a single paradigm and thereby circumventing this issue, the number of experimental animals used is reduced. Furthermore, by avoiding social isolation during testing and without the need to food deprive the animals, the mHB represents a behavioral test system, inducing if any, very low amount of stress.

This protocol describes the modified hole board, which is a behavioral test set-up that comprises the characteristics of an open field and a traditional hole board. This set-up enables the differential analysis of unconditioned behavior of small laboratory mammals as well as the analysis of cognitive abilities.

The Hole Consiglio Modified - Behavior, Cognition e l&#39;interazione sociale in topi e ratti di misura

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure ...

A Novel Experimental and Analytical Approach to the Multimodal Neural Decoding of Intent During Social Interaction in Freely-behaving Human Infants

Understanding typical and atypical development remains one of the fundamental questions in developmental human neuroscience. Traditionally, experimental paradigms and analysis tools have been limited to constrained laboratory tasks and contexts due to technical limitations imposed by the available set of measuring and analysis techniques and the age of the subjects. These limitations severely limit the study of developmental neural dynamics and associated neural networks engaged in cognition, perception and action in infants performing &#8220;in action and in context&#8221;. This protocol presents a novel approach to study infants and young children as they freely organize their own behavior, and its consequences in a complex, partly unpredictable and highly dynamic environment. The proposed methodology integrates synchronized high-density active scalp electroencephalography (EEG), inertial measurement units (IMUs), video recording and behavioral analysis to capture brain activity and movement non-invasively in freely-behaving infants. This setup allows for the study of neural network dynamics in the developing brain, in action and context, as these networks are recruited during goal-oriented, exploration and social interaction tasks.

This protocol presents a novel methodology for the neural decoding of intent from freely-behaving infants during unscripted social interaction with an actor. Neural activity is acquired using non-invasive high-density active scalp electroencephalography (EEG). Kinematic data is collected with inertial measurement units and supplemented with synchronized video recording.

Un nuovo approccio sperimentale e analitico al multimodale neurale decodifica di intenti durante l&#39;interazione sociale in Liberamente-comportarsi neonati umani

Understanding typical and atypical development remains one of the fundamental questions in developmental human neuroscience. Traditionally, experimental ...

A Pressure Injection System for Investigating the Neuropharmacology of Information Processing in Awake Behaving Macaque Monkey Cortex

The top-down modulation of feed-forward cortical information processing is functionally important for many cognitive processes, including the modulation of sensory information processing by attention. However, little is known about which neurotransmitter systems are involved in such modulations. A practical way to address this question is to combine single-cell recording with local and temporary neuropharmacological manipulation in a suitable animal model. Here we demonstrate a technique combining acute single-cell recordings with the injection of neuropharmacological agents in the direct vicinity of the recording electrode. The video shows the preparation of the pressure injection/recording system, including preparation of the substance to be injected. We show a rhesus monkey performing a visual attention task and the procedure of single-unit recording with block-wise pharmacological manipulations.

Here, we show the pressure injection of neuropharmacological substances during single-cell recording in an awake, behaving macaque monkey. This procedure allows pharmacological manipulation in the direct vicinity of a cortical recording site.

Un sistema di iniezione di pressione per Indagare la Neurofarmacologia di Information Processing in Svegliatevi Comportarsi Macaco Cortex

The top-down modulation of feed-forward cortical information processing is functionally important for many cognitive processes, including the modulation ...

Multi-layer Cortical Ca2+ Imaging in Freely Moving Mice with Prism Probes and Miniaturized Fluorescence Microscopy

In vivo circuit and cellular level functional imaging is a critical tool for understanding the brain in action. High resolution imaging of mouse cortical neurons with two-photon microscopy has provided unique insights into cortical structure, function and plasticity. However, these studies are limited to head fixed animals, greatly reducing the behavioral complexity available for study. In this paper, we describe a procedure for performing chronic fluorescence microscopy with cellular-resolution across multiple cortical layers in freely behaving mice. We used an integrated miniaturized fluorescence microscope paired with an implanted prism probe to simultaneously visualize and record the calcium dynamics of hundreds of neurons across multiple layers of the somatosensory cortex as the mouse engaged in a novel object exploration task, over several days. This technique can be adapted to other brain regions in different animal species for other behavioral paradigms.

Multi-layer Cortical Ca2+ Imaging in Freely Moving Mice with Prism Probes and Miniaturized Fluorescence Microscopy

Here, we present a procedure for performing large-scale Ca2+ imaging with cellular-resolution across multiple cortical layers in freely moving mice. Hundreds of active cells can be observed simultaneously using a miniature, head-mounted microscope coupled with an implanted prism probe.

Corticale multistrato Ca<sup&gt; 2+</sup&gt; Imaging nei mouse con movimento libero con sonde a prisma e microscopia a fluorescenza miniaturizzata

In vivo circuit and cellular level functional imaging is a critical tool for understanding the brain in action. High resolution imaging of mouse cortical ...

A Wireless, Bidirectional Interface for In Vivo Recording and Stimulation of Neural Activity in Freely Behaving Rats

In vivo electrophysiology is a powerful technique to investigate the relationship between brain activity and behavior at a millisecond and micrometer scale. However, current methods mostly rely on tethered cable recordings or only use unidirectional systems, allowing either recording or stimulation of neural activity, but not at the same time or same target. Here, a new wireless, bidirectional device for simultaneous multichannel recording and stimulation of neural activity in freely behaving rats is described. The system operates through a single portable head stage that both transmits recorded activity and can be targeted in real-time for brain stimulation using a telemetry-based multichannel software. The head stage is equipped with a preamplifier and a rechargeable battery, allowing stable long-term recordings or stimulation for up to 1 h. Importantly, the head stage is compact, weighs 12 g (including battery) and thus has minimal impact on the animal&#180;s behavioral repertoire, making the method applicable to a broad set of behavioral tasks. Moreover, the method has the major advantage that the effect of brain stimulation on neural activity and behavior can be measured simultaneously, providing a tool to assess the causal relationships between specific brain activation patterns and behavior. This feature makes the method particularly valuable for the field of deep brain stimulation, allowing precise assessment, monitoring, and adjustment of stimulation parameters during long-term behavioral experiments. The applicability of the system has been validated using the inferior colliculus as a model structure.

A Wireless, Bidirectional Interface for In Vivo Recording and Stimulation of Neural Activity in Freely Behaving Rats

A wireless, bidirectional system for multi-channel neural recordings and stimulation in freely behaving rats is introduced. The system is light and compact, thus having minimal impact on the animal&#180;s behavioral repertoire. Moreover, this bidirectional system provides a sophisticated tool to assess causal relationships between brain activation patterns and behavior.

Una connessione Wireless, interfaccia bidirezionale per registrazione In Vivo e la stimolazione dell'attività neurale a comportarsi liberamente ratti

In vivo electrophysiology is a powerful technique to investigate the relationship between brain activity and behavior at a millisecond and micrometer ...

Automated, Long-term Behavioral Assay for Cognitive Functions in Multiple Genetic Models of Alzheimer's Disease, Using IntelliCage

Multiple factors&#8212;such as aging and genes&#8212;are frequently associated with cognitive decline. Genetically modified mouse models of cognitive decline, such as Alzheimer&#39;s disease (AD), have become a promising tool to elucidate the underlying mechanisms and promote the therapeutic advances. An important step is the validation and characterization of expected behavioral abnormality in the models, in the case of AD, cognitive decline. The long-term behavioral investigations of laboratory animals to study the effect of aging demand substantial efforts from researchers. The IntelliCage system is a high-throughput and cost-effective test battery for mice that eliminates the need for daily human handling. Here, we describe how the system is utilized in the long-term phenotyping of a genetic Alzheimer&#39;s disease model, specifically focusing on the cognitive functions. The experiment employs repeated battery of tests that assess spatial learning and executive functions. This cost-effective age-dependent phenotyping allows us to identify the transient and/or permanent effects of genes on various cognitive aspects.

Automated, Long-term Behavioral Assay for Cognitive Functions in Multiple Genetic Models of Alzheimer&#039;s Disease, Using IntelliCage

This paper describes a protocol for cognitive assessments for genetic models of the Alzheimer&#39;s disease using the IntelliCage system, which is a high throughput automated behavioral monitoring system with operant conditioning.

Automatizzato, a lungo termine l'analisi comportamentale per funzioni Cognitive in più modelli di genetici del morbo di Alzheimer, utilizzando IntelliCage

Multiple factors&#8212;such as aging and genes&#8212;are frequently associated with cognitive decline. Genetically modified mouse models of cognitive ...

Simultaneous Recordings of Cortical Local Field Potentials and Electrocorticograms in Response to Nociceptive Laser Stimuli from Freely Moving Rats

Electrocortical responses, elicited by laser heat pulses that selectively activate nociceptive free nerve endings, are widely used in many animal and human studies to investigate the cortical processing of nociceptive information. These laser-evoked brain potentials (LEPs) consist of several transient responses that are time-locked to the onset of laser stimuli. However, the functional properties of the LEP responses are still largely unknown, due to the lack of a sampling technique that can simultaneously record neural activities at the surface of the cortex (i.e., electrocorticogram [ECoG] and scalp electroencephalogram [scalp EEG]) and inside the brain (i.e., local field potential [LFP]). To address this issue, we present here an animal protocol using freely moving rats. This protocol is composed of three main procedures: (1) animal preparation and surgical procedures, (2) a simultaneous recording of ECoG and LFP in response to nociceptive laser stimuli, and (3) data analysis and feature extraction. Specifically, with the help of a 3D-printed protective shell, both ECoG and LFP electrodes implanted on the rat&#39;s skull were securely held together. During data collection, laser pulses were delivered on the rat&#39;s forepaws through gaps in the bottom of the chamber when the animal was in spontaneous stillness. Ongoing white noise was played to avoid the activation of the auditory system by the laser-generated ultrasounds. As a consequence, only nociceptive responses were selectively recorded. Using the standard analytical procedures (e.g., band-pass filtering, epoch extraction, and baseline correction) to extract stimulus-related brain responses, we obtained results showing that LEPs with a high signal-to-noise ratio were simultaneously recorded from ECoG and LFP electrodes. This methodology makes the simultaneous recording of ECoG and LFP activities possible, which provides a bridge of electrocortical signals at the mesoscopic and macroscopic levels, thereby facilitating the investigation of nociceptive information processing in the brain.

We developed a technique that simultaneously records both electrocorticography and local field potentials in response to nociceptive laser stimuli from freely moving rats. This technique helps establish a direct relationship of electrocortical signals at the mesoscopic and macroscopic levels, which facilitates the investigation of nociceptive information processing in the brain.

Registrazioni simultanee di potenziali di campo locale corticale ed Electrocorticograms in risposta a stimoli nocicettivi Laser da liberi di muoversi

Electrocortical responses, elicited by laser heat pulses that selectively activate nociceptive free nerve endings, are widely used in many animal and ...