La ricerca sostenuta da un finanziamento della Midwestern University Ufficio di programmi di ricerca e sponsorizzati. Grazie anche al Fondo Midwestern University animali e Erik Warren.

<ol>
	<li>Butler, P. J., Jones, D. R., Lowenstein, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advances in Comparative Physiology and Biochemistry. 8, 179-364 (1982).</li><li>Butler, P. J., Jones, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiology+of+diving+birds+and+mammals).">Physiology of diving birds and mammals).</a> Physiol. Rev. 77, 837-899 (1997).</li><li>Butler, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+regulation+in+diving+birds+and+mammals.">Metabolic regulation in diving birds and mammals.</a> Resp. Physiol. Neurobiol. 141, 297-315 (2004).</li><li>Foster, G. E., Sheel, A. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+human+diving+response,+its+function,+and+its+control.">The human diving response, its function, and its control.</a> Scand. J. Med. Sci. Sports. 15, 3-12 (2005).</li><li>Lindholm, P., Lundgren, C. E. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+physiology+and+pathophysiology+of+human+breath-hold+diving.">The physiology and pathophysiology of human breath-hold diving.</a> J. Appl. Physiol. 106, 284-292 (2009).</li><li>McCulloch, P. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+for+investigating+the+central+control+of+the+mammalian+diving+response.">Animal models for investigating the central control of the mammalian diving response.</a> Front. Physiol. 3, 1-16 (2012).</li><li>Krogh, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+progress+of+physiology.">The progress of physiology.</a> Am. J. Physiol. 90, 243-251 (1929).</li><li>Panneton, W. M., Gan, Q., Juric, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+rat:+a+laboratory+model+for+studies+of+the+diving+response.">The rat: a laboratory model for studies of the diving response.</a> J. Appl. Physiol. 108, 811-820 (2010).</li><li>Lin, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autonomic+nervous+control+of+cardiovascular+responses+during+diving+in+the+rat.">Autonomic nervous control of cardiovascular responses during diving in the rat.</a> Am. J. Physiol. 227, 601-605 (1974).</li><li>Lin, Y. C., Baker, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+output+and+its+distribution+during+diving+in+the+rat.">Cardiac output and its distribution during diving in the rat.</a> Am. J. Physiol. 228, 733-737 (1975).</li><li>Huang, T. F., Peng, Y. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+the+chemoreceptors+in+diving+bradycardia+in+the+rat.">Role of the chemoreceptors in diving bradycardia in the rat.</a> Jap. J. Physiol. 26, 395-401 (1976).</li><li>Fahlman, A., Bostrom, B. L., Dillon, K. H., Jones, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+genetic+component+of+the+forced+diving+bradycardia+response+in+mammals.">The genetic component of the forced diving bradycardia response in mammals.</a> Front. Physiol. 2, 1-7 (2011).</li><li>Blix, A. S., Folkow, B., Shepher, J. T., Abboud, F. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of Physiology. , 917-944 (1984).</li><li>Kooyman, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diverse+Divers.">Diverse Divers.</a> 200, (1989).</li><li>MacArthur, R. A., Karpan, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+rates+of+muskrats+diving+under+simulated+field+conditions:+persistence+of+the+bradycardia+response+and+factors+modifying+its+expression.">Heart rates of muskrats diving under simulated field conditions: persistence of the bradycardia response and factors modifying its expression.</a> Can. J. Zool. 67, 1783-1792 (1989).</li><li>McCulloch, P. F., Jones, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+influences+on+diving+bradycardia+in+muskrats+(Ondatra+zibethicus).">Cortical influences on diving bradycardia in muskrats (Ondatra zibethicus).</a> Physiol. Zool. 63, 1098-1117 (1990).</li><li>McCulloch, P. F., Dinovo, K. M., Connolly, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cardiovascular+and+endocrine+responses+to+voluntary+and+forced+diving+in+trained+and+untrained+rats.">The cardiovascular and endocrine responses to voluntary and forced diving in trained and untrained rats.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 298, 224-234 (2010).</li><li>Panneton, W. M., Gan, Q., Dahms, T. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiorespiratory+and+neural+consequences+of+rats+brought+past+their+aerobic+dive+limit.">Cardiorespiratory and neural consequences of rats brought past their aerobic dive limit.</a> J. Appl. Physiol. 109, 1256-1269 (2010).</li><li>Chotiyanonta, J. S., DiNovo, K. M., McCulloch, P. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bilateral+sectioning+of+the+anterior+ethmoidal+nerves+does+not+eliminate+the+diving+response+in+voluntarily+diving+rats.">Bilateral sectioning of the anterior ethmoidal nerves does not eliminate the diving response in voluntarily diving rats.</a> Physiol. Reports. 1, (2013).</li><li>Panneton, W. M., Anch, A. M., Panneton, W. M., Gan, Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parasympathetic+preganglionic+cardiac+motoneurons+labeled+after+voluntary+diving.">Parasympathetic preganglionic cardiac motoneurons labeled after voluntary diving.</a> Front. Physiol. 5, 1-10 (2014).</li><li>McCulloch, P. F., Ollenberger, G. P., Bekar, L. K., West, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trigeminal+and+chemoreceptor+contributions+to+bradycardia+during+voluntary+dives+in+rats.">Trigeminal and chemoreceptor contributions to bradycardia during voluntary dives in rats.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 273, 814-822 (1997).</li><li>Ollenberger, G. P., Matte, G., Wilkinson, A. A., West, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relative+distribution+of+blood+flow+in+rats+during+surface+and+submerged+swimming.">Relative distribution of blood flow in rats during surface and submerged swimming.</a> Comp. Biochem. Physiol. A. 119, 271-277 (1998).</li><li>Ollenberger, G. P., West, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distribution+of+regional+cerebral+blood+flow+in+voluntarily+diving+rats.">Distribution of regional cerebral blood flow in voluntarily diving rats.</a> J. Exp. Biol. 201, 549-558 (1998).</li><li>McCulloch, P. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activation+of+the+trigeminal+medullary+dorsal+horn+during+voluntary+diving+in+rats.">Activation of the trigeminal medullary dorsal horn during voluntary diving in rats.</a> Brain Res. 1051, 194-198 (2005).</li><li>Panneton, W. M., 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=Activation+of+brainstem+neurons+by+underwater+diving+in+the+rat.">Activation of brainstem neurons by underwater diving in the rat.</a> Front. Physiol. 3, 1-13 (2012).</li><li>McCulloch, P. F., Panneton, W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activation+of+brainstem+catecholaminergic+neurons+during+voluntary+diving+in+rats.">Activation of brainstem catecholaminergic neurons during voluntary diving in rats.</a> Brain Res. 984, 42-53 (2003).</li><li>McCulloch, P. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Globosa+neurons:+a+distinct+subgroup+of+noradrenergic+neurons+in+the+caudal+pons+of+rats.">Globosa neurons: a distinct subgroup of noradrenergic neurons in the caudal pons of rats.</a> Brain Res. 964, 164-167 (2003).</li><li>Panneton, W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mammalian+diving+response:+an+enigmatic+reflex+to+preserve+life.">The mammalian diving response: an enigmatic reflex to preserve life.</a> Physiology. 28, 284-297 (2013).</li></ol>

L&#39;autore è un consulente per Stoelting Società, e ha fornito la progettazione e le specifiche del McCulloch Dive serbatoio Maze complessiva a loro per fini commerciali.

Ratti nella loro forma selvatici possono e sfruttare gli ambienti semi-acquatici, e spesso tuffarsi sott&#39;acqua, mentre alla ricerca di cibo 6. Così non è troppo sorprendente che i ratti possono essere facilmente addestrati a tuffarsi volontariamente sott&#39;acqua. Le procedure di formazione descritte possono durare fino a 6 settimane, che porteranno i ratti appena svezzati ad una dimensione del corpo utilizzato nella maggior parte atlanti del cervello di ratto adulto (~ 300 g). Così i cervelli di questi animali addestrati saranno più facilmente comparabili alle strutture anatomiche identificati in questi atlanti. Dopo essere stato collocato nella zona di partenza la maggior parte dei ratti inizieranno la loro nuotata sott&#39;acqua entro 20 sec. Tuttavia, di tanto in tanto un topo si richiedere fino a 5 minuti o più prima di iniziare la sua immersione volontaria. Mentre può essere tentati in questa fase di forzare i ratti nel tunnel subacqueo, questo genere deve essere evitata per evitare che i ratti di associare l&#39;acqua con una esperienza negativa. I roditori possono essere testardi e possono initirifiutano alleato per immergersi durante le sessioni di allenamento, ma una volta che si rendono conto l&#39;unico modo per uscire l&#39;acqua è completando l&#39;immersione attraverso il labirinto, di solito iniziano le loro immersioni subito dopo essere stati posti in zona partenza. Un aspetto critico delle procedure di formazione ripetitive e metodiche è che sono condotte in modo tale da ridurre lo stress vissuta dai topi. Lasciando ratti esplorano il loro ambiente, in particolare mentre nella zona finitura tra la prova, sembra ridurre ulteriormente lo stress. I ratti spesso ri-entrare in acqua per nuotare, e / o immergere la testa sott&#39;acqua, mentre ancora seduto sulla piattaforma zona d&#39;arrivo. Questo suggerisce che i ratti non sono intrinsecamente acqua avversione. Inoltre, mentre non è raro per i ratti per la produzione di pellet fecali durante il nuoto o le immersioni, o quando in attesa nella zona d&#39;arrivo, risultati della formazione quotidiane in un minor numero di pellet fecali 17. In generale, il meno stressati i ratti sono durante l&#39;allenamento, il meno pefiletti produrranno. Eventuali pellet fecali che sono prodotte vengono rimossi dalla zona acqua o finitura più presto possibile mantenere l&#39;acqua relativamente pulita. I ratti possono occasionalmente avere nasi sanguinanti durante il nuoto e le immersioni, che possono essere il risultato di insufflazione d&#39;acqua nei passaggi nasali. La comparsa di sangue può essere dovuto a sollecitazioni osmotiche all&#39;interno della mucosa nasale. Mentre in zona arrivo tra studi i ratti saranno pulirsi. Di conseguenza, il sangue dal naso può ottenere ridistribuito sulla testa ratti e muso, dando ai ratti una leggera sfumatura rossastra, soprattutto intorno agli occhi, nel corso di una seduta di allenamento. Inoltre, un ratto occasionale può trovare stressante immersioni e / o avere esperienze subacquee negative (ad esempio, girando intorno e perdersi sott&#39;acqua immersione (vedi nota dopo 5.4.3. Su come evitare che ciò accada)). In questi ratti porfirina può apparire agli angoli dei loro occhi, segnalando uno stress response. La dimensione del serbatoio di immersione sarà in qualche misura determinare i requisiti delle camere. Il serbatoio descritto è progettato per avere ratti nuotare 2-3 cm sotto la superficie dell&#39;acqua tramite un 5 m di lunghezza plexiglas labirinto invia una durata nuoto subacqueo di 10-15 sec 17,19,24,26,27. Qualora un esperimento essere progettato per misurare risposte da una durata dell&#39;immersione più lunga, o da un&#39;immersione profonda subacquea, il serbatoio può essere necessario ri-progettato. I requisiti di camera potrebbero quindi anche cambiare per adattarsi alle dimensioni di una vasca immersione ri-progettato. Se non c&#39;è scarico disponibili pavimento della stanza procedimento, l&#39;acqua dal serbatoio può essere raccolto in un contenitore di grandi dimensioni, come ad esempio un bidone 60 gal può, che possono poi essere svuotato altrove in modo conveniente. La tecnica Fos può essere utilizzato con altri metodi di rilevazione neuronale per identificare e caratterizzare ulteriormente neuroni che fanno parte della circuiteria tronco della risposta immersioni. Per esempio,Fos rilevamento in combinazione con tirosina idrossilasi colorazione ha identificato neuroni catecolaminergici in A1, C1, A2, A5 e aree sub-coeruleus (Figura 6; 26), e neuroni globosa all&#39;interno della zona laterale A7 26,27, che vengono attivati ​​durante volontaria immersioni. Inoltre, Fos rilevamento in combinazione con il tracciante retrogrado tossina colerica ha identificato i corpi cellulari dei motoneuroni vagali cardiaci all&#39;interno della formazione esterna del nucleo ambiguo che vengono attivati ​​durante l&#39;immersione volontaria 20. Indagare l&#39;integrazione nervoso centrale delle risposte cardiorespiratorie a immersione è importante per una serie di ragioni 6,8,28. La risposta immersioni consente animali, compreso l&#39;uomo, di rimanere sott&#39;acqua sommerso senza respirare per periodi di tempo prolungati. La risposta di immersione rappresenta una riorganizzazione funzionale del tronco encefalico controllo omeostatico, e dimostra uno dei più potenti patterns di riflessi autonomi osservati negli animali. La risposta di immersione può anche essere importante clinicamente negli esseri umani come parte del riflesso trigemino-cardiaco, reflex nasofaringeo, e / o di sindrome della morte improvvisa infantile. Infine, la comprensione dei circuiti neuronali che esiste all&#39;interno del tronco cerebrale di ratti vi aiuterà a determinare come corticale segnali afferenti possono modificare tronco cerebrale di base riflessi autonomi. Tutte queste considerazioni rendono studio degli aspetti centrali della risposta immersioni mammiferi intrinsecamente utile e interessante. Usando le procedure descritte per la formazione ratti tuffarsi volontariamente sott&#39;acqua permetterà una migliore indagine degli aspetti centrali della risposta immersione dei mammiferi che sarà l&#39;uso degli animali tuffato forzati. Questo perché le procedure di formazione come descritto 1) ridurre l&#39;attivazione dei circuiti di stress del sistema nervoso centrale, e 2) non attivano CNS circuiti di ricompensa perché ricompense esterne non vengono utilizzati.

The diving response consists of a suite of autonomic reflexes seen in animals of all vertebrate classes 1. In response to submersion under water, this reflexly-induced response consists of apnea, bradycardia and an alteration of blood flow that maintains flow to the heart, brain and exercising muscles while limiting flow to viscera and non-exercising muscles 2. Many of the metabolic and cardiorespiratory aspects of the mammalian diving response have been well investigated 2,3, including those in humans 4,5. However, what has been relatively lacking, until recently, is investigation of the central integrative aspects of the diving response. What happens within the brainstem, and what is the neuronal step-by-step pathway, that connects afferent inputs to efferent outputs during this autonomic reflex? Answering these questions will require an appropriate animal model 6. An adage in comparative physiology, the Krogh principle 7, is that for every research question there is some animal of choice on which the problem can be most conveniently studied. A most appropriate animal for studying the central aspects of the diving response is the rat 6,8. In large part this is due to the fact that the brains of rats have been very well characterized, both anatomically and functionally, and many rat brain atlases are available 6. Additionally the rat is particularly useful in cardiorespiratory research, because the physiology of the rat is well known across all major organ systems, and the rat is well regarded as an animal model in systems biology 6. Finally, the laboratory rat is the domesticated version of the wild Rattus norvegicus, an animal that routinely swims and dives underwater 6. Based on these considerations, the rat is a good choice for studies investigating the central aspects of the mammalian diving response. In comparison, using marine animals to investigate the central aspects of the mammalian diving response would be much more difficult. This is due in large part to marine animals having comparatively large and non-uniformly sized brains, and the relative difficulty and high cost of housing these animals.
Rats have previously been used to investigate many aspects of the mammalian diving response, primarily in situations involving forced underwater submergence 9-12. However many studies in marine and aquatic animals have shown that there can be a differential response to diving based upon whether the submergence was forced or voluntary 2,13. Diving animals may show an extremely intense bradycardia during forced diving but a much less intense bradycardia during voluntary diving. The &#8220;stress&#8221; of forced submergence can significantly change the cardiovascular responses of diving in many animals 14. Small rodents such as muskrats also show a more intense diving response during forced submergence than during voluntary diving 15,16. Thus, if rats are to be used to investigate the central aspects of the mammalian diving response, investigators should be aware that a rat forcibly submerged underwater may produce a response different from that of a voluntarily diving rat. 
The goal of this article is to provide detailed instructions on how to train rats to voluntarily dive underwater. These procedures are not technically difficult, but can be time-consuming. The training is conducted in such a way as to reduce the stressfulness that could otherwise be associated with forced underwater submergence. This voluntary diving technique should minimize activation of central stress pathways and thus better allow investigation of the central aspects of the diving response. By itself, training rats to voluntarily dive underwater generates no data that can be used to investigate the central aspects of the mammalian diving response. Therefore examples of how voluntarily diving rats have been used in conjunction with other physiological and neuroanatomical research techniques, and how the basic dive training may need to be modified to accommodate theses other techniques, are also provided.

<table><tbody><tr><td>McCulloch Diving Tank Maze</td><td>Stoelting Company</td><td>60139</td><td></td></tr><tr><td>1 inch internal diameter tubing&amp;nbsp;</td><td>Fisher</td><td>14-169-63</td><td>Used to fill or drain tank</td></tr><tr><td>Plexiglas rodent restraint device (Economy flat bottomed restrainer)</td><td>Braintree</td><td>FB-M/L&amp;nbsp;</td><td>For forced dives</td></tr><tr><td>Telemetric transmitters&amp;nbsp;</td><td>DSI</td><td>Model PA-C40 (270-0040-008)</td><td>Used to transmit pulsatile arterial blood pressure</td></tr><tr><td>Hand-held antenna wand</td><td>DSI</td><td>Model RLA 3000 (272-5007)</td><td>Used to ensure radio antenna is near to transmitter while rat is negotiating underwater maze</td></tr><tr><td>Intramedic PE50, 0.023&quot; ID</td><td>Fisher</td><td>14-170-12B</td><td>Used as trailing arterial cannula</td></tr><tr><td>N95 mask - Moldex #2300N Series</td><td>Fisher</td><td>19-003-246D</td><td>Used to limit inhalation of rat allergens</td></tr></tbody></table>

training rats to voluntarily dive underwater: investigations of the mammalian diving response

Underwater submergence produces autonomic changes that are observed in virtually all diving animals. This reflexly-induced response consists of apnea, a parasympathetically-induced bradycardia and a sympathetically-induced alteration of vascular resistance that maintains blood flow to the heart, brain and exercising muscles. While many of the metabolic and cardiorespiratory aspects of the diving response have been studied in marine animals, investigations of the central integrative aspects of this brainstem reflex have been relatively lacking. Because the physiology and neuroanatomy of the rat are well characterized, the rat can be used to help ascertain the central pathways of the mammalian diving response. Detailed instructions are provided on how to train rats to swim and voluntarily dive underwater through a 5 m long Plexiglas maze. Considerations regarding tank design and procedure room requirements are also given. The behavioral training is conducted in such a way as to reduce the stressfulness that could otherwise be associated with forced underwater submergence, thus minimizing activation of central stress pathways. The training procedures are not technically difficult, but they can be time-consuming. Since behavioral training of animals can only provide a model to be used with other experimental techniques, examples of how voluntarily diving rats have been used in conjunction with other physiological and neuroanatomical research techniques, and how the basic training procedures may need to be modified to accommodate these techniques, are also provided. These experiments show that voluntarily diving rats exhibit the same cardiorespiratory changes typically seen in other diving animals. The ease with which rats can be trained to voluntarily dive underwater, and the already available data from rats collected in other neurophysiological studies, makes voluntarily diving rats a good behavioral model to be used in studies investigating the central aspects of the mammalian diving response.

Il completamento delle procedure di formazione di nuoto e le immersioni descritte può diminuire lo stress sperimentato da ratti durante le immersioni sott&#39;acqua. I livelli di corticosterone nel sangue indicano che l&#39;allenamento quotidiano ripetitivo diminuisce la stressanti associati alle immersioni volontaria, e ratti addestrati a trovare le immersioni più stressante che essere gestito giornalmente da un essere umano (figura 2; 17). Al contrario, i ratti non addestrati nel protocollo di immersione subacquea trovano volontaria stressante (figura 2; 17). Inoltre, entrambi i ratti allenati e non allenati trovare costretti immersioni la più stressante (figura 2; 17). Le risposte cardiovascolari di nuoto, immersioni volontaria e ratti immersioni forzate sono stati registrati con dispositivi impiantati di telemetria (Figura 3; 8,17-20) e cannule di uscita (Figura 4, 21-23). Subito dopo volontariasommersione, e all&#39;interno di un unico battito, diminuisce la frequenza cardiaca del 78% e la riduzione media della pressione arteriosa del 25% 17. Questi risultati indicano che i ratti spontaneamente immersione presentano le stesse modifiche cardiorespiratori tipicamente osservati in altri animali immersione. Trailing cannule arteriose sono stati utilizzati per iniettare l&#39;atropina antagonista muscarinico, che elimina la bradicardia associati alle immersioni volontaria (figura 4; 21), e per determinare la distribuzione della gittata cardiaca 22, comprese flusso sanguigno cerebrale 23, durante l&#39;immersione volontaria. Cannule finali sono stati utilizzati anche per dimostrare che i ratti ignorano l&#39;aumento ipossiemia arteriosa e ipercapnia mentre sono sommersi 18, e che il pre-esistente unità chemoreceptor non ha alcun effetto sulle risposte cardiovascolari alle immersioni volontaria 21. I neuroni all&#39;interno lamine I e II del corno dorsale midollare ventrale (MDH) esprimere Fos During immersioni volontaria, e questi neuroni possono costituire il primo relè tronco afferente della risposta immersione (figura 5; 24). Tronco encefalico importanti aree di controllo cardiorespiratorio, come ad esempio l&#39;area compressore caudale (CPA), solitari nucleo del tratto (NTS), rostrale midollo ventrolaterale (RVLM), e le regioni peribrachial, tutti mostrano un aumento etichettatura Fos durante l&#39;immersione volontaria rispetto al nuoto 25. I neuroni in regioni chemiosensibili del tronco encefalico esprimono Fos dopo lunga durata costretto immersioni 18. <img alt="Figura 1" fo:content-width="4in" src="/files/ftp_upload/52093/52093fig1highres.jpg" width="400" /> Figura 1:. Schema di Diving Serbatoio Un serbatoio di plexiglas (100 x 60 x 15 cm) è stato utilizzato per creare un labirinto semplice che consiste di cinque canali lunghi 1 m. Il serbatoio è stato riempito con 30 ° C l&#39;acqua di rubinetto, e ratti sono stati inizialmente addestrato a negotiate il labirinto nuotando sulla superficie dell&#39;acqua, Dall&#39;area di avvio (in alto a sinistra) alla zona arrivo (in basso a destra). I ratti sono stati poi addestrati a tuffarsi attraverso il labirinto, tenuto sott&#39;acqua da pezzi di plexiglas orizzontali posti 2-3 cm sotto la superficie dell&#39;acqua. [Questa cifra è stata modificata dal 26] <img alt="Figura 2" fo:content-width="5in" src="/files/ftp_upload/52093/52093fig2highres.jpg" width="500" /> Figura 2: misurazioni corticosterone. I prelievi di sangue dalle vene della coda di ratto sono stati utilizzati per misurare le concentrazioni di corticosterone (media ± SE) da ratti lasciati nelle gabbie (mai trattati in precedenza), i ratti trattati per 10 min / giorno (gestito), ratti addestrati a nuotare e tuffarsi (qualificati), e ratti che ha ricevuto non nuotare o immergersi formazione (inesperti). Corticosterone è stata misurata dopo ratti addestrati avevano completato la loro formazione di nuoto (a sinistra insieme di barre), ratti addestrati dopo aver completato il loro div volontariae formazione (Centro set di barre), e dopo i ratti addestrati avevano completato la loro formazione immersione forzata (giusto insieme di barre). 1 indica il valore è significativamente maggiore di Naïve; 2 indica il valore è significativamente maggiore di trattati; 3 indica il valore è significativamente maggiore rispetto addestrato; * Indica che in Formatosi valore ratti durante l&#39;immersione forzata è significativamente superiore durante l&#39;immersione volontaria. [Questa cifra è stata modificata dal 17] <img alt="Figura 3" fo:content-width="5in" src="/files/ftp_upload/52093/52093fig3highres.jpg" width="500" /> Figura 3: tracce pressione arteriosa da trasmettitori telemetrici tracce di dati grezzi mostrano pulsatile della pressione arteriosa durante il nuoto (colonna di sinistra), immersioni volontaria (colonna centrale), e le immersioni forzata (colonna di destra) da ratti addestrati a nuotare e immergersi nel labirinto. (fila in basso) e da ratti che non avevano avuto il traiprocedura ning (riga in alto). Immersione subacquea (sia volontaria e sommersione forzata) produsse un bradicardia immediata e più lento aumento insorgenza della pressione arteriosa, che nuoto sulla superficie dell&#39;acqua non ha causato tali cambiamenti cardiovascolari. Aperitivo sotto le tracce indicano periodi di sommersione. Le interruzioni di traccia periodi indicano quando il segnale telemetrico è stato perso. [Questa cifra è stata modificata dal 17] <img alt="Figura 4" fo:content-width="5in" src="/files/ftp_upload/52093/52093fig4highres.jpg" width="500" /> Figura 4: Atropina elimina bradicardia immersioni. Le registrazioni originali di pulsatile pressione arteriosa dei ratti volontariamente di immersione (a) prima e (B) dopo atropina pre-trattamento. Tracce sono stati ottenuti utilizzando una cannula arteriosa trascinamento. Prima di atropina pre-trattamento, la pressione arteriosa è diminuito leggermente su di sommersione, ma tgallina aumentata a maggiore di pre-immersione per il resto dell&#39;immersione. La frequenza cardiaca è stata determinata da intervalli di pressione impulsi adiacenti. Dopo l&#39;immersione c&#39;era una bradicardia immediata e sostanziale che è stata mantenuta per tutta la durata dell&#39;immersione. Dopo il blocco parasimpatico da atropina pretrattamento la bradicardia è stato eliminato. C&#39;è stato anche un aumento della pressione arteriosa durante l&#39;immersione. Il bar sotto la traccia indica il periodo di sommersione. [McCulloch, inedito] <img alt="Figura 5" fo:content-width="6in" src="/files/ftp_upload/52093/52093fig5highres.jpg" width="600" /> Figura 5: etichettatura Fos all&#39;interno della MDH. Microfotografie del corno trigemino midollare dorsale (MDH) e il tratto spinale del trigemino (SP5) nei ratti addestrati a tuffarsi sott&#39;acqua. (A) In un ratto di controllo che non ha ripetutamente immergersi non vi è alcuna etichettatura Fos. (B) In un ratto piscina vi è molto accesotle Fos etichetta nella MDH (grande punta di freccia) o nucleo paratrigeminal (piccola freccia) all&#39;interno SP5. (C) In un ratto immersioni c&#39;è più etichettatura Fos ventrale sia nella MDH (grande punta di freccia) e il nucleo paratrigeminal (piccole frecce) rispetto al il ratto di nuoto e di controllo. Inserire nel pannello (A) indica la posizione rostrale-caudale di pannelli AC. Barra di scala nel pannello C è di 100 micron. [Questa cifra è stata modificata dal 24] <img alt="Figura 6" fo:content-width="5in" src="/files/ftp_upload/52093/52093fig6highres.jpg" width="500" /> Figura 6: Attivato catecolaminergici neuroni di ratti di immersione. Microfotografie mostrano il midollo di un topo non immersione di controllo (A, C ed E) e un ratto volontariamente immersione (B, D e F). Il tessuto cerebrale è stata immunoistologico elaborato sia per un Fosd tirosina idrossilasi (TH), che produce marrone somas TH e nuclei Fos nero. Punte di freccia aperte identificano con etichetta singola neuroni TH-positivi, mentre le frecce solidi identificare Fos + neuroni TH doppio marcato. Neuroni A1 sono identificati nei neuroni A e B. C1 sono identificati in C e D. neuroni A5 sono identificati in E e F. Più Fos e TH doppio etichettati sono visti in A1, C1, e le regioni A5 del ratto immersione di nel ratto controllo non immersioni. Barra di calibrazione in E è per i pannelli AF, ed è di 250 micron. Barra di calibrazione in inserto in F è per tutti inserti, ed è di 50 micron. [Questa cifra è stata modificata dal 26]

Watch this Scientific Journal Video about Training Rats to Voluntarily Dive Underwater: Investigations of the Mammalian Diving Response at JoVE.com

Training Rats to Voluntarily Dive Underwater: Investigations of the Mammalian Diving Response

Detailed instructions are provided on how to train rats to voluntarily dive underwater through a 5 m long Plexiglas maze. Because the brains of rats have been very well characterized, voluntarily diving rats may help elucidate the central pathways of the mammalian diving response.

I ratti di formazione per immersione subacquea volontariamente: Indagini della risposta Diving mammiferi

Underwater submergence produces autonomic changes that are observed in virtually all diving animals. This reflexly-induced response consists of apnea, a ...

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12.2K Views.  Midwestern University. Detailed instructions are provided on how to train rats to voluntarily dive underwater through a 5 m long Plexiglas maze. Because the brains of rats have been very well characterized, voluntarily diving rats may help elucidate the central pathways of the mammalian diving response.

Video: Training Rats to Voluntarily Dive Underwater: Investigations of the Mammalian Diving Response

Shallow Water (Paddling) Variants of Water Maze Tests in Mice

When Richard Morris devised his water maze in 19817, most behavioral work was done in rats. However, the greater understanding of mouse genetics led to the mouse becoming increasingly important. But researchers found that some strains of mutant mice were prone to problems like passively floating or diving when they were tested in the Morris water maze11. This was unsurprising considering their natural habitat; rats swim naturally (classically, the "sewer rat"), whereas mice evolved in the dry areas of central Asia.
To overcome these problems, it was considered whether shallow water would be a sufficient stimulus to provide escape motivation for mice. This would also avoid the problems of drying the small creatures with a towel and then putting them in a heated recovery chamber to avoid hypothermia, which is a much more serious problem than with rats; the large ratio of surface area to volume of a mouse makes it particularly vulnerable to rapid heat loss.
Another consideration was whether a more natural escape strategy could be used, to facilitate learning. Since animals that fall into water and swim away from the safety of the shore are unlikely to pass on their genes, animals have evolved a natural tendency to swim to the edge of a body of water. The Morris water maze, however, requires them to swim to a hidden platform towards the center of the maze - exactly opposite to their evolved behavior. Therefore the paddling maze should incorporate escape to the edge of the apparatus. This feature, coupled with the use of relatively non-aversive shallow water, embodies the "Refinement" aspect of the "3 Rs" of Russell and Burch8.
Various types of maze design were tried; the common feature was that the water was always shallow (2 cm deep) and escape was via a tube piercing the transparent wall of the apparatus. Other tubes ("false exits") were also placed around the walls but these were blocked off. From the inside of the maze all false exits and the single true exit looked the same. Currently a dodecagonal (12-sided) maze is in use in Oxford, with 12 true/false exits set in the corners. In a recent development a transparent paddling Y-maze has been tested successfully.

Shallow Water Paddling Variants of Water Maze Tests in Mice

Mice can swim, but many strains appear to find this activity stressful. To overcome this problem mazes have been devised where escape from shallow water is used to motivate behaviour. These have been demonstrated to support learning at least as good as the traditional and widely used Morris water maze.

Acque poco profonde (Paddling) Varianti di test labirinto d&#39;acqua nei topi

When Richard Morris devised his water maze in 19817, most behavioral work was done in rats. However, the greater understanding of mouse genetics led to ...

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Comportamento

The Forced Swim Test as a Model of Depressive-like Behavior

The goal of the present protocol is to describe the forced swim test (FST), which is one of the most commonly used assays for the study of depressive-like behavior in rodents. The FST is based on the assumption that when placing an animal in a container filled with water, it will first make efforts to escape but eventually will exhibit immobility that may be considered to reflect a measure of behavioral despair. This test has been extensively used because it involves the exposure of the animals to stress, which was shown to have a role in the tendency for major depression. Additionally, the FST has been shown to share some of the factors that are influenced or altered by depression in humans, including changes in food consumption, sleep abnormalities and drug-withdrawal-induced anhedonia. The main advantages of this procedure are that it is relatively easy to perform and that its results are easily and quickly analyzed. Moreover, its sensitivity to a broad range of antidepressant drugs that makes it a suitable screening test is one of the most important features leading to its high predictive validity. Despite its appeal, this model has a number of disadvantages. First, the issue of chronic augmentation is problematic in this test because in real life patients need to be treated for at least several weeks before they experience any relief from their symptoms. Last, due to the aversiveness of the FST, it is important to take into account possible influences it might have on brain structure/function if brain analyses are to be carried out following this procedure.

This protocol describes the forced swim test, which is used for the study of depressive-like behavior in rodents. This procedure involves placing an animal in a container filled with water that eventually will lead to the exhibition of immobility behavior, which is considered to reflect behavioral despair.

Il Swim test forzato come modello di depressione-come Behavior

The goal of the present protocol is to describe the forced swim test (FST), which is one of the most commonly used assays for the study of depressive-like ...

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 ...

A New Method for Inducing a Depression-Like Behavior in Rats

Contagious depression is a phenomenon that is yet to be fully recognized and this stems from insufficient material on the subject. At the moment, there is no existing format for studying the mechanism of action, prevention, containment, and treatment of contagious depression. The purpose of this study, therefore, was to establish the first animal model of contagious depression.
Healthy rats can contract depressive behaviors if exposed to depressed rats. Depression is induced in rats by subjecting them to several manipulations of chronic unpredictable stress (CUS) over 5 weeks, as described in the protocol. A successful sucrose preference test confirmed the development of depression in the rats. The CUS-exposed rats were then caged with na&#239;ve rats from the contagion group (1 na&#239;ve rat/2 depressed rats in a cage) for an additional 5 weeks. 30 social groups were created from the combination of CUS-exposed rats and na&#239;ve rats.
This proposed depression-contagion protocol in animals consists mainly of cohabiting CUS-exposed and healthy rats for 5 weeks. To ensure that this method works, a series of tests are carried out - first, the sucrose preference test upon inducing depression to rats, then, the sucrose preference test, alongside the open field and forced-swim tests at the end of the cohabitation period. Throughout the experiment, rats are given tags and are always returned to their cages after each test.
A few limitations to this method are the weak differences recorded between the experimental and control groups in the sucrose preference test and the irreversible traumatic outcome of the forced swim test. These may be worth considering for suitability before any future application of the protocol. Nonetheless, following the experiment, na&#239;ve rats developed contagion depression after 5 weeks of sharing the same cage with the CUS-exposed rats.

This protocol describes a new model by which healthy rats could contract depression over a given time periodthrough contagion by exposure to chronic unpredictable stressed (CUS) rats.

Un nuovo metodo per indurre un comportamento depressione-come in ratti

Contagious depression is a phenomenon that is yet to be fully recognized and this stems from insufficient material on the subject. At the moment, there is ...

The Dig Task: A Simple Scent Discrimination Reveals Deficits Following Frontal Brain Damage

Cognitive impairment is the most frequent cause of disability in humans following brain damage, yet the behavioral tasks used to assess cognition in rodent models of brain injury is lacking. Borrowing from the operant literature our laboratory utilized a basic scent discrimination paradigm1-4 in order to assess deficits in frontally-injured rats. Previously we have briefly described the Dig task and demonstrated that rats with frontal brain damage show severe deficits across multiple tests within the task5. Here we present a more detailed protocol for this task. Rats are placed into a chamber and allowed to discriminate between two scented sands, one of which contains a reinforcer. The trial ends after the rat either correctly discriminates (defined as digging in the correct scented sand), incorrectly discriminates, or 30 sec elapses. Rats that correctly discriminate are allowed to recover and consume the reinforcer. Rats that discriminate incorrectly are immediately removed from the chamber. This can continue through a variety of reversals and novel scents. The primary analysis is the accuracy for each scent pairing (cumulative proportion correct for each scent). The general findings from the Dig task suggest that it is a simple experimental preparation that can assess deficits in rats with bilateral frontal cortical damage compared to rats with unilateral parietal damage. The Dig task can also be easily incorporated into an existing cognitive test battery. The use of more tasks such as this one can lead to more accurate testing of frontal function following injury, which may lead to therapeutic options for treatment. All animal use was conducted in accordance with protocols approved by the Institutional Animal Care and Use Committee.

In this protocol, a novel application of scent discrimination is described. The Dig task is a reasonably inexpensive task that can be used to assess frontally-mediated cognition following brain damage.

Il compito Dig: Un profumo semplice discriminazione rivela deficit in seguito al danneggiamento frontale del cervello

Cognitive impairment is the most frequent cause of disability in humans following brain damage, yet the behavioral tasks used to assess cognition in ...

Neuroscienze

Automated Rat Single-Pellet Reaching with 3-Dimensional Reconstruction of Paw and Digit Trajectories

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the behavior. Several automated versions of skilled reaching have been developed recently. Here, we describe a version that automatically presents pellets to rats while recording high-definition video from multiple angles at high frame rates (300 fps). The paw and individual digits are tracked with DeepLabCut, a machine learning algorithm for markerless pose estimation. This system can also be synchronized with physiological recordings, or be used to trigger physiologic interventions (e.g., electrical or optical stimulation).

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the behavior. We describe an automated version of skilled reaching with motion tracking and three-dimensional reconstruction of reach trajectories.

Acquisto automatico di ratti a pellet con ricostruzione tridimensionale delle traiettorie di paw e cifre

Rodent skilled reaching is commonly used to study dexterous skills, but requires significant time and effort to implement the task and analyze the ...

A Complex Diving-For-Food Task to Investigate Social Organization and Interactions in Rats

For many species, where status is a vital motivator that can affect health, social hierarchies influence behavior. Social hierarchies that include dominant-submissive relationships are common in both animal and human societies. These relationships can be affected by interactions with others and with their environment, making them difficult to analyze in a controlled study. Rather than a simple dominance hierarchy, this formation has a complicated presentation that allows rats to avoid aggression. Status can be stagnant or mutable, and results in complex societal stratifications. Here we describe a complex diving-for-food task to investigate rodent social hierarchy and behavioral interactions. This animal model may allow us to assess the relationship between a wide range of mental illnesses and social organization, as well as to study the effectiveness of therapy on social dysfunction.

This protocol describes a method of examining social hierarchy in a rat model. Rats perform a complex diving-for-food task in which they form a distinct hierarchy according to their willingness to dive underwater and swim to obtain a food pellet. This method is used to understand decision making and social relationships among highly social animals in small groups.

Un complesso compito subacqueo per il cibo per indagare l'organizzazione sociale e le interazioni nei ratti

For many species, where status is a vital motivator that can affect health, social hierarchies influence behavior. Social hierarchies that include ...

<meta charset="utf8"></head><body>Esplorare l'esercizio materno per il benessere della prole di ratto

Swimming Exercise Protocol and Care Methods for Pregnant Rats

The developmental origins of health and disease concept highlights the impact of early environments on chronic non-communicable diseases like diabetes, cardiovascular disease, and cancer. Studies using animal models have investigated how maternal factors such as undernutrition, overnutrition, obesity, and exposure to chemicals or hypoxia affect fetal development and offspring health, leading to issues like low birth weight, high blood pressure, dyslipidemia, and insulin resistance. Given the increasing prevalence of overweight and obesity among reproductive-age women, effective interventions are critical. Maternal exercise during pregnancy has emerged as a key intervention, benefiting both mother and offspring and reducing the risk of disease. This study compares the differences of three exercise models on pregnant rats: voluntary wheel running, motorized treadmills, and swimming. Swimming is the most beneficial option due to its safe and controlled intensity levels. This protocol details the rat breeding methods, swimming training during pregnancy, and post-breeding nursing protocols. This model, suitable for various rat and mouse species, is useful for studying the benefits of maternal exercise on offspring health and intergenerational wellness.

<meta charset="utf8"></head><body>Autore in primo piano: Migliorare la salute della prole nei ratti con l'esercizio materno durante la gravidanza

Here, we present a protocol to delineate rat breeding methods, swimming training procedures, and post-breeding nursing protocols for pregnant rats after training. This protocol provides an animal model for studying the effects of maternal exercise during pregnancy on offspring and its underlying mechanisms.

Protocollo di esercizio di nuoto e metodi di cura per i ratti gravidi

The developmental origins of health and disease concept highlights the impact of early environments on chronic non-communicable diseases like diabetes, ...

I ratti di formazione per immersione subacquea volontariamente: Indagini della risposta Diving mammiferi

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Acque poco profonde (Paddling) Varianti di test labirinto d'acqua nei topi

Il Swim test forzato come modello di depressione-come Behavior

The Double-H labirinto: una prova comportamentale robusto per l'apprendimento e la memoria nei roditori

Un nuovo metodo per indurre un comportamento depressione-come in ratti

Il compito Dig: Un profumo semplice discriminazione rivela deficit in seguito al danneggiamento frontale del cervello

Acquisto automatico di ratti a pellet con ricostruzione tridimensionale delle traiettorie di paw e cifre

Un complesso compito subacqueo per il cibo per indagare l'organizzazione sociale e le interazioni nei ratti

Protocollo di esercizio di nuoto e metodi di cura per i ratti gravidi

Protocollo di esercizio di nuoto e metodi di cura per i ratti gravidi

Protocollo di esercizio di nuoto e metodi di cura per i ratti gravidi