Gli autori desiderano ringraziare il signor Akihiro Hirano per la sua assistenza nella produzione dell'apparato su misura. Gli autori vorrei ringraziare il signor Kosuke Takahashi e il signor Shingo Nakajima per la loro assistenza tecnica. Questo lavoro è stato supportato dalla ricerca sul rischio delle sostanze chimiche, salute e assegni di ricerca di laboratorio Scienze, Ministero della salute, del lavoro e Welfare, Giappone (H25-KAGAKU-IPPANN-003) e A Research Project Grant dall'Istituto di scienza e tecnologia Meiji Università, Giappone.

Tutte le procedure sperimentali descritte qui sono state approvate dalla istituzionale Animal Care e uso Comitato di Meiji University (IACUC 14-0002(1)). Animali utilizzati nei risultati rappresentativi sono stati preparati come segue: ratti maschi Sprague-Dawley sono stati acquistati da una società di animali di laboratorio e stabulati in gruppo di 4 animali per gabbia standard del ratto (W200 × D410 × H250 mm) per almeno una settimana prima dell'inizio della esperimento del comportamento. La camera di stabulazione degli animali era mantenuto in condizioni ambientali standard per luce (12:12 orario di chiaro/scuro con luci alle 10:00 h), temperatura (25,0 ± 0,5 ° C), umidità (55 ± 10%) e ventilazione (10 volte / h), e gli animali hanno avuti ad libitum accesso a cibo ( Oriental lievito Co. Ltd., Tokyo, Giappone) e acqua. Gli animali erano tenuti in una gabbia di standard del ratto (W410 x D250 x H200 mm, Toyoriko Co., Ltd., Aichi, Giappone) con carta biancheria da letto (alfa-dri, LSG Corporatin, Tokyo, Giappone).
1. elevato più l'analisi del labirinto
<ol><li>Impostare più elevati labirinto apparato in un contenitore su misura (W1, 500 × D1, 500 × H2, 000mm) (Figura 1A) con un quadro di metallo a forma di più 500 mm sopra il pavimento per supportare l'esecuzione braccia di modo (Figura 1B), illuminazione a soffitto, contenitore per illuminare la superficie del labirinto per l'intensità della luce necessaria (Figura 1) e una videocamera digitale nel soffitto centro per abilitare il monitoraggio dei video dal vivo dei test comportamentali (Figura 1).</li>
	<li>Fissare i bracci (x W100 L500 mm) sul quadro a forma di più e quindi fissare la piattaforma centrale quadrata (W100 x D100 mm) al centro dei quattro bracci (Figura 1 -F). Nota: Nel nostro laboratorio, abbiamo due tipi di braccia aperte (x W100 L500 mm) e due tipi di bracciolo chiuso (L500 x W100 x H450 mm) (Figura 1). Il bracciolo chiuso hanno pareti trasparente o opache (Figura 1), e le braccia aperte sono progettate con o senza una breve cengia (H5 mm, Figura 1E). La piattaforma centrale quadrata (W100 × D100 mm) è posto al centro dei quattro bracci (Figura 1 -F). Così, le seguenti quattro combinazioni di armi possono essere allestite secondo scopo sperimentale: open arms con sporgenze + bracciolo chiuso con pareti trasparenti (sporgenze/trasparente), braccia aperte con sporgenze + bracciolo chiuso con pareti opache (sporgenze/opaco), a braccia aperte senza sporgenze + bracciolo chiuso con pareti trasparenti (No-sporgenze/trasparente) e le braccia aperte senza sporgenze + bracciolo chiuso con opaco pareti (No-sporgenze/opaco). La superficie della pista braccio è nera, per consentire il migliore animale traccia dal software di analisi di comportamento automatizzato, come descritto nella sezione 2, analisi comportamentale.</li>
	<li>Regolare l'intensità di illuminazione sulla superficie della parte distale di ogni braccio e la piattaforma centrale per circa 100 Lux.</li>
	<li>Prima di ogni prova, pulire l'intero apparato con soluzione di etanolo 70% e pulire con acqua distillata.</li>
	<li>Fare clic sul pulsante"record" sul registratore su disco rigido per avviare la videocamera digitale che registra comportamento del ratto per la video analisi descritta in sezione 2, analisi comportamentale di imaging.</li>
	<li>Posizionare un animale sulla piattaforma centrale rivolto verso un braccio aperto e consentire la libera esplorazione sull'apparecchio per 5 min.</li>
	<li>Fare clic sul pulsante"stop" sul registratore su disco rigido per completare la registrazione.</li>
	<li>Contare il numero di feci e le minzioni sono dopo il ritorno l'animale sottoposto a test per la camera di stabulazione degli animali.</li>
	<li>Ripetere dal passo 1.4 fino alla fine dell'esperimento. Nota: Esecuzione di un test a secco viene sempre effettuata prima di iniziare ogni esperimento per verificare che tutte le impostazioni sperimentali sono impostate correttamente prima di eventuali animali da esperimento sono esposti a condizioni sperimentali. In caso contrario, alcuni animali, soprattutto il primo animale potrebbe verificarsi diverse condizioni ambientali (ad es., rumori possibilmente indotti dallo sperimentatore durante la manipolazione e/o animale spunti eventualmente lasciati dall'animale precedentemente testato). Nota: Quando un animale è in fase di test, gli sperimentatori sono vicino al contenitore. Così, anche se gli sperimentatori non sono visibili il ratto può ancora essere in grado di percepire loro via odore e/o suono.</li>
</ol>2. behavioral Analysis
Nota: Analisi comportamentale viene eseguita tramite l'osservazione manuale e software di analisi automatico.
<ol><li>
Osservazione manuale
	<ol>
<li>Dopo che l'animale è posto sul davanzale, osservare le seguenti indicazioni: numero delle voci (una voce su un braccio è definita come qualsiasi istanza quando tutti i 4 zampe sono sul braccio), il tempo trascorso su ciascun braccio, e numero di frequentanti allungato posture un braccio aperto di fronte , mentre tirando indietro la piattaforma centrale verso un braccio chiuso.</li>
		<li>Misurare la durata e la frequenza dei comportamenti sopra definito da cronometro e conteggio per 5 min, a partire da quando sono chiuse le porte del contenitore.</li>
	</ol>
</li>
	<li>
Analisi automatizzata
	<ol>
<li>Utilizzando il programma di software disponibile, registrare i seguenti: distanza percorsa, il tempi trascorso in diverse posizioni su braccia aperte (segmenti prossimali, medio e distale dalla piattaforma centrale), e un minuto per minuto analisi del tempo trascorso su aperto e chiuso braccia.</li>
		<li>Fare clic sul pulsante"start" del software di analisi automatizzati allo stesso tempo come l'osservazione manuale inizia (la registrazione si ferma automaticamente se è impostata la durata della registrazione). Nota: Il software di analisi comportamentale utilizzato in questo studio tracce dell'animale tramite il contrasto con il campo di sfondo; l'animale, che viene assegnata una dimensione fissa, viene identificato come l'oggetto più luminoso e quindi utilizzabile per la tracciabilità degli animali la locomozione del suo punto centrale.</li>
	</ol>
</li>
</ol>

<ol><li>Nestler, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Role+of+the+Brain%27s+Reward+Circuitry+in+Depression%3A+Transcriptional+Mechanisms%5BTitle%5D)+AND+%22Int+Rev+Neurobiol%22%5BJournal%5D)">Role of the Brain's Reward Circuitry in Depression: Transcriptional Mechanisms.</a> Int Rev Neurobiol. 124, 151-170 (2015).</li>
<li>Crabbe, J. C., Wahlsten, D., Dudek, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Genetics+of+mouse+behavior%3A+interactions+with+laboratory+environment%5BTitle%5D)+AND+%22Science%22%5BJournal%5D)">Genetics of mouse behavior: interactions with laboratory environment.</a> Science. 284 (5420), 1670-1672 (1999).</li>
<li>Handley, S. L., Mithani, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Effects+of+alpha-adrenoceptor+agonists+and+antagonists+in+a+maze-exploration+model+of+%27fear%27-motivated+behaviour%5BTitle%5D)+AND+%22Naunyn+Schmiedebergs+Arch+Pharmacol%22%5BJournal%5D)">Effects of alpha-adrenoceptor agonists and antagonists in a maze-exploration model of 'fear'-motivated behaviour.</a> Naunyn Schmiedebergs Arch Pharmacol. 327 (1), 1-5 (1984).</li>
<li>Pellow, S., Chopin, P., File, S. E., Briley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Validation+of+open%3Aclosed+arm+entries+in+an+elevated+plus-maze+as+a+measure+of+anxiety+in+the+rat%5BTitle%5D)+AND+%22J+Neurosci+Methods%22%5BJournal%5D)">Validation of open:closed arm entries in an elevated plus-maze as a measure of anxiety in the rat.</a> J Neurosci Methods. 14 (3), 149-167 (1985).</li>
<li>Violle, N., Balandras, F., Le Roux, Y., Desor, D., Schroeder, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Variations+in+illumination%2C+closed+wall+transparency+and%2For+extramaze+space+influence+both+baseline+anxiety+and+response+to+diazepam+in+the+rat+elevated+plus-maze%5BTitle%5D)+AND+%22Behav+Brain+Res%22%5BJournal%5D)">Variations in illumination, closed wall transparency and/or extramaze space influence both baseline anxiety and response to diazepam in the rat elevated plus-maze.</a> Behav Brain Res. 203 (1), 35-42 (2009).</li>
<li>Hogg, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+review+of+the+validity+and+variability+of+the+elevated+plus-maze+as+an+animal+model+of+anxiety%5BTitle%5D)+AND+%22Pharmacol+Biochem+Behav%22%5BJournal%5D)">A review of the validity and variability of the elevated plus-maze as an animal model of anxiety.</a> Pharmacol Biochem Behav. 54 (1), 21-30 (1996).</li>
<li>Martinez, J. C., Cardenas, F., Lamprea, M., Morato, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+role+of+vision+and+proprioception+in+the+aversion+of+rats+to+the+open+arms+of+an+elevated+plus-maze%5BTitle%5D)+AND+%22Behav+Processes%22%5BJournal%5D)">The role of vision and proprioception in the aversion of rats to the open arms of an elevated plus-maze.</a> Behav Processes. 60 (1), 15-26 (2002).</li>
<li>Anseloni, V. Z., Brandao, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Ethopharmacological+analysis+of+behaviour+of+rats+using+variations+of+the+elevated+plus-maze%5BTitle%5D)+AND+%22Behav+Pharmacol%22%5BJournal%5D)">Ethopharmacological analysis of behaviour of rats using variations of the elevated plus-maze.</a> Behav Pharmacol. 8 (6-7), 533-540 (1997).</li>
<li>Anseloni, V. Z., Motta, V., Lima, G., Brandao, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Behavioral+and+pharmacological+validation+of+the+elevated+plus+maze+constructed+with+transparent+walls%5BTitle%5D)+AND+%22Braz+J+Med+Biol+Res%22%5BJournal%5D)">Behavioral and pharmacological validation of the elevated plus maze constructed with transparent walls.</a> Braz J Med Biol Res. 28 (5), 597-601 (1995).</li>
<li>Hagenbuch, N., Feldon, J., Yee, B. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Use+of+the+elevated+plus-maze+test+with+opaque+or+transparent+walls+in+the+detection+of+mouse+strain+differences+and+the+anxiolytic+effects+of+diazepam%5BTitle%5D)+AND+%22Behav+Pharmacol%22%5BJournal%5D)">Use of the elevated plus-maze test with opaque or transparent walls in the detection of mouse strain differences and the anxiolytic effects of diazepam.</a> Behav Pharmacol. 17 (1), 31-41 (2006).</li>
<li>Fernandes, C., File, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+influence+of+open+arm+ledges+and+maze+experience+in+the+elevated+plus-maze%5BTitle%5D)+AND+%22Pharmacol+Biochem+Behav%22%5BJournal%5D)">The influence of open arm ledges and maze experience in the elevated plus-maze.</a> Pharmacol Biochem Behav. 54 (1), 31-40 (1996).</li>
<li>Horii, Y., Kawaguchi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Higher+detection+sensitivity+of+anxiolytic+effects+of+diazepam+by+ledge-free+open+arm+with+opaque+walled+closed+arm+elevated+plus+maze+in+male+rats%5BTitle%5D)+AND+%22Behav+Brain+Res%22%5BJournal%5D)">Higher detection sensitivity of anxiolytic effects of diazepam by ledge-free open arm with opaque walled closed arm elevated plus maze in male rats.</a> Behav Brain Res. 294, 131-140 (2015).</li>
<li>Santos, R. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Evaluation+of+the+effect+of+acute+sibutramine+in+female+rats+in+the+elevated+T-maze+and+elevated+plus-maze+tests%5BTitle%5D)+AND+%22Basic+Clin+Pharmacol+Toxicol%22%5BJournal%5D)">Evaluation of the effect of acute sibutramine in female rats in the elevated T-maze and elevated plus-maze tests.</a> Basic Clin Pharmacol Toxicol. 114 (2), 181-187 (2014).</li>
<li>Lynn, D. A., Brown, G. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+ontogeny+of+anxiety-like+behavior+in+rats+from+adolescence+to+adulthood%5BTitle%5D)+AND+%22Dev+Psychobiol%22%5BJournal%5D)">The ontogeny of anxiety-like behavior in rats from adolescence to adulthood.</a> Dev Psychobiol. 52 (8), 731-739 (2010).</li>
<li>Horii, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Male+Hatano+high-avoidance+rats+show+high+avoidance+and+high+anxiety-like+behaviors+as+compared+with+male+low-avoidance+rats%5BTitle%5D)+AND+%22Exp+Anim%22%5BJournal%5D)">Male Hatano high-avoidance rats show high avoidance and high anxiety-like behaviors as compared with male low-avoidance rats.</a> Exp Anim. 61 (5), 517-524 (2012).</li>
<li>Walf, A. A., Frye, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+use+of+the+elevated+plus+maze+as+an+assay+of+anxiety-related+behavior+in+rodents%5BTitle%5D)+AND+%22Nat+Protoc%22%5BJournal%5D)">The use of the elevated plus maze as an assay of anxiety-related behavior in rodents.</a> Nat Protoc. 2 (2), 322-328 (2007).</li>
<li>Yang, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Behavioral+and+pharmacological+investigation+of+anxiety+and+maternal+responsiveness+of+postpartum+female+rats+in+a+pup+elevated+plus+maze%5BTitle%5D)+AND+%22Behav+Brain+Res%22%5BJournal%5D)">Behavioral and pharmacological investigation of anxiety and maternal responsiveness of postpartum female rats in a pup elevated plus maze.</a> Behav Brain Res. 292, 414-427 (2015).</li>
<li>Albani, S. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Behavior+in+the+elevated+plus+maze+is+differentially+affected+by+testing+conditions+in+rats+under+and+over+three+weeks+of+age%5BTitle%5D)+AND+%22Front+Behav+Neurosci%22%5BJournal%5D)">Behavior in the elevated plus maze is differentially affected by testing conditions in rats under and over three weeks of age.</a> Front Behav Neurosci. 9, 31(2015).</li>
</ol>

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Aumenta il numero di pazienti affetti da disturbi psichiatrici, tra cui il disturbo d'ansia, è importante sviluppare studi all'avanguardia per migliorare la comprensione del meccanismo di base di ansia. Per raggiungere questo obiettivo, è anche importante ottimizzare le procedure sperimentali. Di conseguenza, per migliorare l'applicazione di elevato più la prova del labirinto, abbiamo dimostrato l'effetto delle caratteristiche di braccio sui risultati sperimentali utilizzando ratti.
L'eleva...

Il numero di pazienti affetti da disturbi dell'umore, tra cui disturbi di ansia e depressione, è in aumento. Anche se lo sviluppo di questi disturbi coinvolge fattori sia genetici che ambientali, i meccanismi patogeni dettagliati non sono ancora pienamente compreso1. Pertanto, la ricerca ha bisogno di concentrarsi su scoprendo i meccanismi di fondo dei disturbi dell'umore, come pure lo sviluppo di farmaci efficaci che hanno meno effetti collaterali.
Test comportamentali per animali da laboratorio sono utili per indagare la funzione superiore del cervello, tra cui emozione. Come comportamento animale è altamente variabile, risultati sperimentali spesso differiscono tra laboratori, anche se era un ceppo inbred identico utilizzati2. Così, i ricercatori devono anche comprendere le caratteristiche di base dei dispositivi sperimentali adottate al fine di fornire risultati affidabili, precisi nel laboratorio.
L'elevato più prova del labirinto è stata istituita per esaminare la reattività emozionale in roditori3,4. L'intero apparato è solitamente situato 500 mm sopra il pavimento e si compone di due aperte e due braccia chiuse che fanno una forma plus. Misurazioni di esplorazione di braccio (compresa la durata e la frequenza delle voci su ciascun braccio), passi comportamenti viaggiati e specificati come frequentanti allungato postura degli animali sottoposti sono registrate durante i periodi d'osservazioni. Da queste misure, animale ansia è stimato come un risultato sperimentale.
L'elevato plus prova del labirinto è utilizzato in tutto il mondo, ma non tutti i laboratori utilizzano la stessa apparecchiatura design5,6, e queste differenze possono influenzare i risultati sperimentali. Ad esempio, le differenze includono la presenza o l'assenza di sporgenze lungo le braccia aperte e/o l'utilizzo di pareti trasparenti o opache per bracciolo chiuso5,6. Le sporgenze lungo a braccia aperte e l'uso di pareti trasparenti per bracciolo chiuso sono stati sviluppati per evitare gli animali cadere l' apparato7e per facilitare le osservazioni comportamentali all'interno dei bracci chiusi, rispettivamente8,9. Anche se ci sono stati alcuni studi che hanno esaminato come i singoli differenze nella struttura del braccio possono influenzare la capacità di rilevare animale ansia1,2,5,10,11 , gli effetti combinati di open (con/senza sporgenza breve) e chiuso (trasparente/opaco pareti) braccio caratteristiche il comportamento animale non è stato ancora studiato.
In un recente rapporto, abbiamo discusso l'effetto di queste combinazioni di disegni di braccio sul comportamento del tipo di ansia in ratti12. In breve, sporgenze braccio aperto aumentato significativamente l'ansia-come comportamento in ratti, mentre le braccia trasparenti possono inoltre sono diminuite questo comportamento. Inoltre, abbiamo verificato più alta sensibilità di rilevazione dell'effetto di un farmaco ansiolitico in una combinazione di braccio aperto no-coralline + braccio chiusa murata opaco rispetto con una combinazione di coralline braccio aperto + braccio chiusa murata trasparente. In questo rapporto, sarà a introdurre il nostro protocollo per l'elevato oltre a labirinto prova, insieme con la discussione dei risultati chiave dalla relazione precedente. Riteniamo che questa relazione fornirà informazioni utili per coloro che sono impiegati o che prevede di utilizzare l'elevato più labirinto nei loro studi.

<table><tbody><tr><td>Customized container (W1500 &amp;times; D1500 &amp;times; H2000 mm)</td><td>NA</td><td>NA</td><td>Handmade by Mr. Akihiro Hirano</td></tr><tr><td>Lighting</td><td>NA</td><td>NA</td><td>Handmade by Mr. Akihiro Hirano</td></tr><tr><td>Elevated plus maze apparatus</td><td>NA</td><td>NA</td><td>Handmade by Mr. Akihiro Hirano</td></tr><tr><td>Digital video camera</td><td>Watec</td><td>WAT-250D2</td><td>Any suitable video camera can be attached to a hard disk recorder for recording tracking profiles.</td></tr><tr><td>Hard disk recorder</td><td>TOSHIBA</td><td>RD-R200</td><td>Any suitable hard disk recorder can be attached to the digital video camera.</td></tr><tr><td>Sprague-Dawley rats</td><td>Charles River Laboratories Japan, Inc.</td><td>NA</td><td>Any suitable rats can be used for your study</td></tr><tr><td>Standard rat cage</td><td>Toyoriko</td><td>TP-105</td><td>Any suitable rat cage be used for your study</td></tr><tr><td>Instrument to measure light intensity</td><td>AS ONE</td><td>1-5818-02</td><td>Any suitable instrument to measure light intensity</td></tr><tr><td>EthoVision XT version 8.0</td><td>Noldus</td><td>NA</td><td>Any suitable software to measure animal behavior</td></tr><tr><td>Diazepam</td><td>Taiyo Pharmaceutical Industry</td><td>1124402A2061</td><td>Any suitable drug can be used for your study</td></tr><tr><td>Tween 80</td><td>Wako Pure Chemical Industries</td><td>9005-65-6</td><td>Any suitable drug can be used for your study</td></tr></tbody></table>

testing animal anxiety in rats: effects of open arm ledges and closed arm wall transparency in elevated plus maze test

L'elevato più prova del labirinto è un test comportamento per la valutazione animale ansia nei roditori. Anche se questo test è ampiamente applicato nel campo della scienza del comportamento, risultati contraddittori sono spesso forniti da diversi laboratori. Per identificare i motivi per i diversi risultati, precedentemente ci siamo concentrati sulle caratteristiche di braccio, che differiscono tra i laboratori, la maggior parte in particolare la presenza/assenza di sporgenze ai lati delle braccia aperte e la trasparenza/opacità delle pareti braccio chiuso. In un rapporto precedente, abbiamo utilizzato un contenitore personalizzato progettato per confrontare il comportamento di ratto su diverse combinazioni di disegni di braccio aperto e chiuso in condizioni sperimentali altrimenti identiche e ha mostrato che le differenze nelle funzionalità di braccio interferiscano con sperimentale risultati. In breve, sporgenze braccio aperto aumentato significativamente l'ansia-come comportamento in ratti, mentre le braccia trasparenti possono inoltre sono diminuite questo comportamento. Inoltre, abbiamo verificato una maggiore sensibilità di rilevazione dell'effetto di un farmaco ansiolitico in una combinazione di braccio aperto no-coralline + braccio chiusa murata opaco rispetto con una combinazione di coralline braccio aperto + braccio chiusa murata trasparente. In questo rapporto, presentiamo il nostro protocollo per l'elevato più la prova del labirinto, con discussione dei risultati chiavi dalla precedente relazione e la nostra esperienza sperimentale. Riteniamo che questa relazione fornirà informazioni utili per i ricercatori che hanno impiegato o che prevede di utilizzare l'elevato più labirinto nei loro studi.

Nello studio precedente, abbiamo confrontato gli effetti combinati di sporgenze braccio aperto e trasparenza delle pareti braccio chiuso sui comportamenti esplorativi sul labirinto12. Ratti significativamente speso molto meno tempo a braccia aperte senza sporgenze rispetto su braccia aperte con sporgenze (F [1, 60] = 13,49, P = 0,0005) (Figura 2A). Risultati simili inoltre sono stati trovati per il numero di voci in braccia ap...

Watch this Scientific Journal Video about Testing Animal Anxiety in Rats: Effects of Open Arm Ledges and Closed Arm Wall Transparency in Elevated Plus Maze Test at JoVE.com

Testing Animal Anxiety in Rats: Effects of Open Arm Ledges and Closed Arm Wall Transparency in Elevated Plus Maze Test

Sperimentazione animale ansia in ratti: effetti di sporgenze braccio aperto e chiuso braccio parete trasparenza in Elevated Plus Maze Test

Comportamento del tipo di ansia dei ratti testati da elevato più labirinto varia molto a seconda dell'ambiente di test. Qui vi mostriamo come impostazioni di apparato, particolare struttura a braccio, influenzano il comportamento sul labirinto, e spieghiamo un protocollo affidabile per rilevare gli effetti di farmaci ansiolitici. Questa relazione contribuirà alla ricerca di ansia.

The elevated plus maze test is a behavioral test for assessing animal anxiety in rodents. Although this test is widely applied in the field of behavioral ...

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13.5K Views.  Meiji University. Comportamento del tipo di ansia dei ratti testati da elevato più labirinto varia molto a seconda dell'ambiente di test. Qui vi mostriamo come impostazioni di apparato, particolare struttura a braccio, influenzano il comportamento sul labirinto, e spieghiamo un protocollo affidabile per rilevare gli effetti di farmaci ansiolitici. Questa relazione contribuirà alla ricerca di ansia.

Video: Testing Animal Anxiety in Rats: Effects of Open Arm Ledges and Closed Arm Wall Transparency in Elevated Plus Maze Test

The Successive Alleys Test of Anxiety in Mice and Rats

The plus-maze was derived from the early work of Montgomery. He observed that rats tended to avoid the open arms of a maze, preferring the enclosed ones. Handley, Mithani and File et al. performed the first studies on the plus-maze design we use today, and in 1987 Lister published a design for use with mice. 
Time spent on, and entries into, the open arms are an index of anxiety; the lower these indices, the more anxious the mouse is. Alternatively, a mouse that spends most of its time in the closed arms is classed as anxious. 
One of the problems of the plus-maze is that, while time spent on, and entries into, the open arms is a fairly unambiguous measure of anxiety, time in the central area is more difficult to interpret, although time spent here has been classified as &#x201C;decision making&#x201D;. In many tests central area time is a considerable part of the total test time.
Shepherd et al. produced an ingenious design to eliminate the central area, which they called the &#x201C;zero maze&#x201D;. However, although used by several groups, it has never been as widely adopted as the plus-maze. 
In the present article I describe a modification of the plus-maze design that not only eliminates the central area but also incorporates elements from other anxiety tests, such as the light-dark box and emergence tests. It is a linear series of four alleys, each having increasing anxiogenic properties. It has given similar results to the plus-maze in general. Although it may not be more sensitive than the plus-maze (more data is needed before a firm conclusion can be reached on this point), it provides a useful confirmation of plus-maze results which would be useful when, for example, only a single example of a mutant mouse was available, as, for example, in ENU-based mutagenesis programs.

The plus-maze measures anxiety-like behaviour in rodents. There are two opposite closed and two opposite open arms; anxious rodents avoid the open arms. The central area is neither completely open nor closed, so time spent here is ambiguous and difficult to interpret. Here a modification of the plus-maze protocol eliminating this area is described.

Le successive Vicoli test di ansia nei topi e nei ratti

The plus-maze was derived from the early work of Montgomery. He observed that rats tended to avoid the open arms of a maze, preferring the enclosed ones.  ...

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Comportamento

Barnes Maze Testing Strategies with Small and Large Rodent Models

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g.&#160;bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g.&#160;distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e.&#160;random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g.&#160;shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug/ toxicant exposure.

The dry-land Barnes maze is widely used to measure spatial navigation ability in response to mildly aversive stimuli. Over consecutive days, performance (e.g.&#160;latency to locate escape cage) of control subjects improves, indicative of normal learning and memory. Differences between rats and mice necessitate apparatus and methodology changes that are detailed here.

Barnes strategie di sperimentazione Maze con piccole e grandi modelli di roditori

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land ...

Use of the Open Field Maze to Measure Locomotor and Anxiety-like Behavior in Mice

Animal models have proven to be invaluable to researchers trying to answer questions regarding the mechanisms of behavior. The Open Field Maze is one of the most commonly used platforms to measure behaviors in animal models. It is a fast and relatively easy test that provides a variety of behavioral information ranging from general ambulatory ability to data regarding the emotionality of the subject animal. As it relates to rodent models, the procedure allows the study of different strains of mice or rats both laboratory bred and wild-captured. The technique also readily lends itself to the investigation of different pharmacological compounds for anxiolytic or anxiogenic effects. Here, a protocol for use of the open field maze to describe mouse behaviors is detailed and a simple analysis of general locomotor ability and anxiety-related emotional behaviors between two strains of C57BL/6 mice is performed. Briefly, using the described protocol we show Wild Type mice exhibited significantly less anxiety related behaviors than did age-matched Knock Out mice while both strains exhibited similar ambulatory ability.

A protocol is provided to use an Open Field Maze to access general locomotor activity, anxiety and emotionality in a laboratory mouse model.

L&#39;uso del campo aperto Maze misurare Locomotore e ansia-come comportamento nei topi

Animal models have proven to be invaluable to researchers trying to answer questions regarding the mechanisms of behavior. The Open Field Maze is one of ...

The Double-H Maze: A Robust Behavioral Test for Learning and Memory in Rodents

Spatial cognition research in rodents typically employs the use of maze tasks, whose attributes vary from one maze to the next. These tasks vary by their behavioral flexibility and required memory duration, the number of goals and pathways, and also the overall task complexity. A confounding feature in many of these tasks is the lack of control over the strategy employed by the rodents to reach the goal, e.g., allocentric (declarative-like) or egocentric (procedural) based strategies. The double-H maze is a novel water-escape memory task that addresses this issue, by allowing the experimenter to direct the type of strategy learned during the training period. The double-H maze is a transparent device, which consists of a central alleyway with three arms protruding on both sides, along with an escape platform submerged at the extremity of one of these arms.
Rats can be trained using an allocentric strategy by alternating the start position in the maze in an unpredictable manner (see protocol 1; &#167;4.7), thus requiring them to learn the location of the platform based on the available allothetic cues. Alternatively, an egocentric learning strategy (protocol 2; &#167;4.8) can be employed by releasing the rats from the same position during each trial, until they learn the procedural pattern required to reach the goal. This task has been proven to allow for the formation of stable memory traces.
Memory can be probed following the training period in a misleading probe trial, in which the starting position for the rats alternates. Following an egocentric learning paradigm, rats typically resort to an allocentric-based strategy, but only when their initial view on the extra-maze cues differs markedly from their original position. This task is ideally suited to explore the effects of drugs/perturbations on allocentric/egocentric memory performance, as well as the interactions between these two memory systems.

The goal of this protocol is to investigate spatial cognition in rodents. The double-H water maze is a novel test, which is particularly useful to elucidate the different components of learning, consolidation and memory, as well as the interplay of memory systems.

The Double-H labirinto: una prova comportamentale robusto per l&#39;apprendimento e la memoria nei roditori

Spatial cognition research in rodents typically employs the use of maze tasks, whose attributes vary from one maze to the next. These tasks vary by their ...

Quantifying Cognitive Decrements Caused by Cranial Radiotherapy

With the exception of survival, cognitive impairment stemming from the clinical management of cancer is a major factor dictating therapeutic outcome. For many patients afflicted with CNS and non-CNS malignancies, radiotherapy and chemotherapy offer the best options for disease control. These treatments however come at a cost, and nearly all cancer survivors (~11 million in the US alone as of 2006) incur some risk for developing cognitive dysfunction, with the most severe cases found in patients subjected to cranial radiotherapy (~200,000/yr) for the control of primary and metastatic brain tumors1. Particularly problematic are pediatric cases, whose long-term survival plagued with marked cognitive decrements results in significant socioeconomic burdens2. To date, there are still no satisfactory solutions to this significant clinical problem.
We have addressed this serious health concern using transplanted stem cells to combat radiation-induced cognitive decline in athymic rats subjected to cranial irradiation3. Details of the stereotaxic irradiation and the in vitro culturing and transplantation of human neural stem cells (hNSCs) can be found in our companion paper (Acharya et al., JoVE reference). Following irradiation and transplantation surgery, rats are then assessed for changes in cognition, grafted cell survival and expression of differentiation-specific markers 1 and 4-months after irradiation. To critically evaluate the success or failure of any potential intervention designed to ameliorate radiation-induced cognitive sequelae, a rigorous series of quantitative cognitive tasks must be performed. To accomplish this, we subject our animals to a suite of cognitive testing paradigms including novel place recognition, water maze, elevated plus maze and fear conditioning, in order to quantify hippocampal and non-hippocampal learning and memory. We have demonstrated the utility of these tests for quantifying specific types of cognitive decrements in irradiated animals, and used them to show that animals engrafted with hNSCs exhibit significant improvements in cognitive function3.
The cognitive benefits derived from engrafted human stem cells suggest that similar strategies may one day provide much needed clinical recourse to cancer survivors suffering from impaired cognition. Accordingly, we have provided written and visual documentation of the critical steps used in our cognitive testing paradigms to facilitate the translation of our promising results into the clinic.

Cognitive impairment resulting from the radiotherapeutic management of brain tumors represents a clinically intractable condition that adversely impacts quality of life. The capability to critically evaluate potential interventions for ameliorating radiation-induced cognitive decrements ultimately depends on the capability to undertake rigorous quantitative assessments of cognition.

Quantificare Decrementa cognitivi causati da radioterapia craniale

With the exception of survival, cognitive impairment stemming from the clinical management of cancer is a major factor dictating therapeutic outcome. For ...

Medicina

Utilizing the Modified T-Maze to Assess Functional Memory Outcomes After Cardiac Arrest

Background: Evaluating mild to moderate cognitive impairment in a global cerebral ischemia (i.e. cardiac arrest) model can be difficult due to poor locomotion after surgery. For example, rats who undergo surgical procedures and are subjected to the Morris water maze may not be able to swim, thus voiding the experiment.
New Method: We established a modified behavioral spontaneous alternation T-maze test. The major advantage of the modified T-maze protocol is its relatively simple design that is powerful enough to assess functional learning/memory after ischemia. Additionally, the data analysis is simple and straightforward. We used the T-maze to determine the rats&#39; learning/memory deficits both in the presence or absence of mild to moderate (6 min) asphyxial cardiac arrest (ACA). Rats have a natural tendency for exploration and will explore the alternate arms in the T-maze, whereas hippocampal-lesioned rats tend to adopt a side-preference resulting in decreased spontaneous alternation ratios, revealing the hippocampal-related functional learning/memory in the presence or absence of ACA.
Results: ACA groups have higher side-preference ratios and lower alternations as compared to control.
Comparison with Existing Method(s): The Morris water and Barnes maze are more prominent for assessing learning/memory function. However, the Morris water maze is more stressful than other mazes. The Barnes maze is widely used to measure reference (long-term) memory, while ACA-induced neurocognitive deficits are more closely related to working (short-term) memory.
Conclusions: We have developed a simple, yet effective strategy to delineate working (short-term) memory via the T-maze in our global cerebral ischemia model (ACA).

This protocol describes the use of a modified T-maze to evaluate functional learning/memory in asphyxia cardiac arrest-induced cerebral ischemia.

Utilizzando il t-labirinto modificate per valutare i risultati funzionali di memoria dopo arresto cardiaco

Background: Evaluating mild to moderate cognitive impairment in a global cerebral ischemia (i.e. cardiac arrest) model can be difficult due to poor ...

Elevated Plus Maze for Mice

Although the mouse genome is now completely sequenced, the functions of most of the genes expressed in the brain are not known. The influence of a given gene on a specific behavior can be determined by behavioral analysis of mutant mice. If a target gene is expressed in the brain, behavioral phenotype of the mutant mice could elucidate the genetic mechanism of normal behaviors. The elevated plus maze test is one of the most widely used tests for measuring anxiety-like behavior. The test is based on the natural aversion of mice for open and elevated areas, as well as on their natural spontaneous exploratory behavior in novel environments. The apparatus consists of open arms and closed arms, crossed in the middle perpendicularly to each other, and a center area. Mice are given access to all of the arms and are allowed to move freely between them. The number of entries into the open arms and the time spent in the open arms are used as indices of open space-induced anxiety in mice. Unfortunately, the procedural differences that exist between laboratories make it difficult to duplicate and compare results among laboratories. Here, we present a detailed movie demonstrating our protocol for the elevated plus maze test. In our laboratory, we have assessed more than 90 strains of mutant mice using the protocol shown in the movie. These data will be disclosed as a part of a public database that we are now constructing.
Visualization of the protocol will promote better understanding of the details of the entire experimental procedure, allowing for standardization of the protocols used in different laboratories and comparisons of the behavioral phenotypes of various strains of mutant mice assessed using this test. 


The elevated plus maze test is one of the most widely used tests for measuring anxiety-like behavior in mice. Here, we present a movie showing the detailed procedures for conducting the test.

Elevata Maze Plus per topi

Although the mouse genome is now completely sequenced, the functions of most of the genes expressed in the brain are not known. The influence of a given ...

Biologia

Elevated Plus Maze Test Combined with Video Tracking Software to Investigate the Anxiolytic Effect of Exogenous Ketogenic Supplements

The overall goal of this study is to describe the methodology of the elevated plus maze (EPM) test in combination with a video tracking software. The purpose of the method is to document the effect of various potential anxiolytic treatments on laboratory rodent models. The EPM test is based on the rodents&#39; proclivity toward protected, enclosed dark spaces and unconditioned fear of open spaces and heights, and their innate intense motivation to explore novel environments. The EPM test is a widely used behavioral test for investigating the anxiolytic or anxiogenic responses of rodents given drugs that are known to affect behavior. Observation demonstrating a decreased proportion of time spent on closed arms, an increased proportion of time spent on open arms, a reduced number of entries to closed arms, and an elevated number of entries to open arms measured by the EPM test may reflect reduced anxiety levels. Using this method, the effect of exogenous ketone supplements on anxiety-related behavior is tested in Sprague Dawley (SPD) rats. Exogenous ketone supplements are chronically fed to the rats for 83 days or subchronically and acutely orally gavaged, daily for 7 days, before conducting the EPM test. Behavioral data collection is performed using the SMART video tracking system by a blinded observer at the end of the treatments. The main findings indicate that the EPM test is an effective method to detect the ketone supplement-induced anxiolytic effect and can be considered a sensitive measure to assess changes in anxiety behavior associated with drug- or metabolic-based therapies.

Here, we present a protocol to investigate changes in the anxiety level of rodent animal models. The elevated plus maze (EPM) test, used together with a video tracking software, provides a reliable method to document the effect of various potential anxiolytic treatments in preclinical laboratory scenarios.

Elevato oltre a Test combinato con Video Software di monitoraggio per studiare l'effetto ansiolitico dei supplementi chetogenica esogeni del labirinto

The overall goal of this study is to describe the methodology of the elevated plus maze (EPM) test in combination with a video tracking software. The ...

Utilizing a Reconfigurable Maze System to Enhance the Reproducibility of Spatial Navigation Tests in Rodents

Several maze shapes are used to test spatial navigation performance and behavioral phenotypes. Traditionally, each experiment requires a unique maze shape, thus requiring several separate mazes in different configurations. The maze geometry cannot be reconfigured in a single environment to accommodate scalability and reproducibility. The reconfigurable maze is a unique approach to address the limitations, allowing quick and flexible configurations of maze pathways in a repeatable manner. It consists of interlocking pathways and includes feeders, treadmills, movable walls, and shut-off sensors. The current protocol describes how the reconfigurable maze can replicate existing mazes, including the T-shaped, plus-shaped, W-shaped, and figure-eight mazes. Initially, the T-shaped maze was constructed inside a single experimental room, followed by modifications. The rapid and scalable protocol outlined herein demonstrates the flexibility of the reconfigurable maze, achieved through the addition of components and behavioral training phases in a stepwise manner. The reconfigurable maze systematically and precisely assesses the performance of multiple aspects of spatial navigation behavior.

The present protocol describes a reconfigurable maze, a unique system for testing spatial navigation and behavioral phenotypes in rodents. The adaptability of this maze system enables the execution of various experiments in a single physical environment. The ease of structural rearrangement generates reliable and reproducible experimental results.

Utilizzo di un sistema di labirinto riconfigurabile per migliorare la riproducibilità dei test di navigazione spaziale nei roditori

Several maze shapes are used to test spatial navigation performance and behavioral phenotypes. Traditionally, each experiment requires a unique maze ...

Validazione di un modello murino della sindrome di Angelman mediante test comportamentali

Behavioral Characterization of an Angelman Syndrome Mouse Model

This manuscript describes a battery of behavioral tests available to characterize Angelman syndrome (AS)-like phenotypes in an established murine model of AS. We use the rotarod learning paradigm, detailed gait analysis, and nest building test to detect and characterize animal motor impairments. We test animal emotionality in the open field and elevated plus maze tests, as well as the affect in the tail suspension test. When AS mice are tested in the open field test, the results should be interpreted with care, since motor dysfunctions influence mouse behavior in the maze and alter activity scores.
The reproducibility and effectiveness of the presented behavioral tests has already been validated in several independent Uba3a mouse lines with different knockout variants, establishing this set of tests as an excellent validation tool in AS research. Models with the relevant construct and face validity will warrant further investigations to elucidate the pathophysiology of the disease and grant the development of causal treatments.

Autore in primo piano: una batteria di test comportamentali altamente riproducibili per convalidare un modello murino della sindrome di Angelman 

This manuscript presents a set of highly reproducible behavioral tests to validate an Angelman syndrome mouse model.

Caratterizzazione comportamentale di un modello murino con sindrome di Angelman

This manuscript describes a battery of behavioral tests available to characterize Angelman syndrome (AS)-like phenotypes in an established murine model of ...

Sperimentazione animale ansia in ratti: effetti di sporgenze braccio aperto e chiuso braccio parete trasparenza in Elevated Plus Maze Test

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