Il Wellcome Trust per il finanziamento Open Access all&#39;Università di Oxford. Robert Deacon è un membro del gruppo OXION Oxford, finanziato dal Wellcome Trust concessione WT084655MA.

1. Apparato Provino rovesciata di 1,1 Kondziela La schermata invertita è un quadrato di rete metallica composta da 12 millimetri quadrati da 1 mm filo diametro (Figura 1) 43 cm. E &#39;circondata da una profondità di cm 4 perline di legno (che impedisce il mouse occasionale che cerca di di salire sul l&#39;altro lato) (Figura 2). 1.2 Test Weights Sette pesi costituiscono l&#39;apparato. Ogni alloggio è composto di una palla di filo aggrovigliato multa calibro acciaio inossidabile, un &quot;collettore di scala&quot;, come utilizzato per prevenire la formazione di calcare scala in bollitori domestici. Il peso di questa è piccola (7 g), ma ogni collettore scala è attaccato ad una serie di collegamenti di catena, ciascuno del peso di circa 13 g. Il numero di collegamenti varia da uno a sette. I loro pesi sono quindi: 20, 33, 46, 59, 72, 85 e 98 g (Figure 3 e 4). 2. Proprocedura Per tutti i test, portare i topi alla sala sperimentale 5-20 minuti prima del test per garantire che siano correttamente sveglio. Come regola generale, per consentire il recupero della forza muscolare e di un ritorno ai normali livelli di eccitazione, riposare i topi da un ritorno alla gabbia a casa dopo ogni prova del motore. <ol><li> Provino rovesciata di Kondziela </li><li> Procedimento: Posizionare il mouse al centro della schermata di maglia del filo, avviare un cronometro, ruotare lo schermo in una posizione invertita oltre 2 secondi, con la testa del topo in declino prima. Tenere lo schermo costantemente 40-50 cm al di sopra di una superficie imbottita. Nota del tempo quando il mouse cade, o rimuoverla quando viene raggiunto il criterio di tempo di 60 sec. Volte criterio più lunghi possono essere utili per alcuni esperimenti. </li><li> Segnando la schermata invertita: </li></ol> Caduta tra 1-10 sec = 1 Caduta tra 11-25 sec = 2 Caduta tra 26-60 sec = 3 Caduta dopo 60 sec = 4 Oppure, ad esempio per 2 min: Caduta tra 1-10 sec = 1 Caduta tra 11-25 sec = 2 Caduta tra 26-60 sec = 3 Caduta tra 61-90 sec = 4 Cade dopo 90 secondi = 5 3. Pesi di prova Tenere un mouse dalla base centrale / della coda e abbassarla per permettergli di cogliere il primo peso (20 g), che è disteso sul banco di laboratorio. Come si coglie il collezionista scala fili con le zampe anteriori, avviare un orologio di arresto e sollevare il mouse fino a quando il collegamento è chiaro della panchina. Una sospensione di tre secondi è il criterio. Se il mouse diminuisce il peso in meno di 3 sec, prendere nota del tempo che tiene il peso. Appoggiare il mouse per circa 10 secondi e provarlo sul peso, ancora una volta. Se fallisce tre volte, che termina il processo, e il mouse viene assegnato il tempo / peso massimo raggiunto. Se si tiene per 3 sec poi provare sul prossimo peso più pesante. Se si solleva questo per 3 sec, testarlo sul prossimo più pesante, dopo avertestato tutti i suoi cagemates sul primo peso. Anche in questo caso, si è dato tre possibilità di tenere il peso per 3 sec. Un punteggio totale finale è calcolato come il prodotto del numero di anelli della catena pesante tenuto per l&#39;intero 3 sec, moltiplicata per il tempo (sec) è posseduta. Se il peso più pesante è caduto prima di 3 secondi viene calcolato un valore intermedio appropriato. Così un mouse in possesso di un peso di 5-link per 3 secondi, ma in grado di sollevare un peso di 6-link, viene assegnato un punteggio di (5 x 3) = 15. Se si tiene il peso 6-link per 1 secondo, i punteggi (5 x 3) + (1) = 16. Talvolta topi non possono essere adeguatamente motivati ​​per afferrare l&#39;apparato. Questo si verifica in genere negli animali più vecchi. Questo problema può essere minimizzato tenendo i topi dalla coda per un tempo più lungo prima di portare all&#39;interno della distanza di presa della palla filo.

<ol><li>Bulfield, G., Siller, W. G., Wight, P. A., Moore, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((K.J.X+chromosome-linked+muscular+dystrophy+%28mdx%29+in+the+mouse%5BTitle%5D)+AND+%22Proc.+Natl.+Acad.+Sci.+U.S.A%22%5BJournal%5D)">K.J.X chromosome-linked muscular dystrophy (mdx) in the mouse.</a> Proc. Natl. Acad. Sci. U.S.A. 81, 1189-1192 (1984).</li>
<li>Contet, C., Rawlins, J. N. P., Deacon, R. M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+comparison+of+129S2%2FSvHsd+and+C57BL%2F6JOlaHsd+mice+on+a+test+battery+assessing+sensorimotor%2C+affective+and+cognitive+behaviours%3A+implications+for+the+study+of+genetically+modified+mice%5BTitle%5D)+AND+%22Behavioural+Brain+Research%22%5BJournal%5D)">A comparison of 129S2/SvHsd and C57BL/6JOlaHsd mice on a test battery assessing sensorimotor, affective and cognitive behaviours: implications for the study of genetically modified mice.</a> Behavioural Brain Research. 124, 33-46 (2001).</li>
<li>Deacon, R. M. J., Brook, R. C., Meyer, D., Haeckel, O., Ashcroft, F. M., Miki, T., Seino, S., Liss, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Behavioral+phenotyping+of+mice+lacking+the+KATP+channel+subunit+Kir6.2%5BTitle%5D)+AND+%22Physiol.+Behav%22%5BJournal%5D)">Behavioral phenotyping of mice lacking the KATP channel subunit Kir6.2.</a> Physiol. Behav. 87, 723-733 (2006).</li>
<li>Deacon, R. M. J., Croucher, A., Rawlins, J. N. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hippocampal+cytotoxic+lesion+effects+on+species-typical+behaviors+in+mice%5BTitle%5D)+AND+%22Behav.+Brain+Res%22%5BJournal%5D)">Hippocampal cytotoxic lesion effects on species-typical behaviors in mice.</a> Behav. Brain Res. 132, 203-213 (2002).</li>
<li>Rawlins, J. N. P., Morley, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+comparison+of+the+behavior+of+C57BL%2F6+and+C57BL%2F10+mice%5BTitle%5D)+AND+%22Behav.+Brain+Res%22%5BJournal%5D)">A comparison of the behavior of C57BL/6 and C57BL/10 mice.</a> Behav. Brain Res. 179, 239-247 (2007).</li>
<li>Guenther, K., Deacon, R. M. J., Perry, V. H., Rawlins, J. N. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Early+behavioural+changes+in+scrapie-affected+mice+and+the+influence+of+dapsone%5BTitle%5D)+AND+%22Eur.+J.+Neurosci%22%5BJournal%5D)">Early behavioural changes in scrapie-affected mice and the influence of dapsone.</a> Eur. J. Neurosci. 14, 401-409 (2001).</li>
<li>Kondziela, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Eine+neue+method+zur+messung+der+muskularen+relaxation+bei+weissen+mausen%5BTitle%5D)+AND+%22Arch.+Int.+Pharmacodyn%22%5BJournal%5D)">Eine neue method zur messung der muskularen relaxation bei weissen mausen.</a> Arch. Int. Pharmacodyn. 152, 277-284 (1964).</li>
</ol>

Nessun conflitto di interessi dichiarati.

Modelli murini delle molte malattie che colpiscono i sistemi motori umani sono in costante sviluppo, quindi buoni saggi di resistenza nei topi sono essenziali. Alcuni esempi sono le molte forme di distrofia muscolare, morbo di Parkinson e la corea di Huntington. Saggi di Forza inoltre trovare impiego in modelli di rigenerazione dei nervi dopo danno del nervo spinale o periferico. Industriale e incidenti automobilistici continuano a causare notevoli disabilità per gli esseri umani, ma molto lavoro preclinico è attualmente indagando le possibili vie di trattamento basate su fattori di crescita nervosi. I muscoli non lavorano individualmente. Essi vengono attivati ​​dal cervello, locale o superiori riflessi spinali, attraverso le giunzioni neuromuscolari e di lavoro all&#39;interno dei vincoli di altri muscoli e del sistema scheletrico. Pertanto, la complessità del sistema significa Prove in vivo di forza muscolare nel animale sveglio sono essenziali nella valutazione della sua condizione attuale e la effects di eventuali trattamenti putativi. I topi istintivamente aggrapparsi a materiali con una presa forte, così Mus musculus è un animale modello ideale per valutare disturbi della forza muscolare e possibili trattamenti.

Per un laico, l&#39;idea di misurare la forza nei topi potrebbe apparire assurdo, anche qualcosa di un ossimoro. Tuttavia, non è senza ragione che casa / laboratorio topi sono chiamati Mus musculus. In realtà hanno un elevato rapporto robustezza / peso, maggiore di quella dei ratti. Per esempio, topi adulti possono facilmente sostenere il proprio peso corporeo, anche utilizzando solo la prua o zampe posteriori; pochissimi topi da laboratorio per adulti possono fare questo. I topi stanno giocando un ruolo sempre più importante nella ricerca biomedica. Essi possono essere utilizzati per modellare molti disturbi motori, sia somatiche umane e del sistema nervoso centrale in origine. I primi includono i più di trenta forme di distrofia muscolare ereditaria 1 e miastenia gravis, mentre esempi di quest&#39;ultimo caso sono sclerosi multipla, atrofia muscolare spinale, morbo di Parkinson, morbo di Huntington e la sclerosi laterale amiotrofica. Per tutti questi modelli, una valutazione completa dei loro deficit motori deve includere test specificidi forza.

measuring the strength of mice

Kondziela 7 ideato il provino invertito e lo pubblicò nel 1964. Si tratta di una prova di forza muscolare utilizzando tutti e quattro gli arti. Topi più normale facilmente punteggio massimo in questo compito, è una schermata lordo veloce ma insensibile, e la prova di pesi descritto in questo articolo fornisce una misura più fine della forza muscolare. Ci sono anche diversi pezzi indicatore a base di deformazione di apparecchi disponibili in commercio in grado di fornire dati più graduali rispetto al provino rovesciata, ma il loro costo può metterli fuori dalla portata di molti laboratori che non si specializzano in prove di resistenza. Quindi nel 2000 un apparato economico e semplice è stato ideato dall&#39;autore. Si compone di una serie di maglie della catena di lunghezza crescente, allegata ad un &quot;collettore pelliccia&quot; una palla di finissima rete metallica venduto per prevenire la formazione di calcare in zone con acqua dura. Un&#39;osservazione casuale ha rivelato che i topi potevano afferrare questi molto stretto, in modo che si è rivelato ideale come poin presat per un apparecchio di sollevamento pesi. Un errore comune con metri forza commerciale è che il bar o altro grip non è abbastanza sottile per i topi di esercitare un grip massimo. Come regola generale, più sottile è il filo o barra, meglio un mouse può afferrare con i suoi piccoli artigli. Questa è una prova di forza pura, anche se come per qualsiasi prova fattori motivazionali potrebbero svolgere un ruolo. L&#39;uso di collettori di scala, tuttavia, sembra per minimizzare i problemi motivazionali come la motivazione sembra essere molto elevato per la maggior parte giovani topi adulti normali.

Risultati attesi Contet et al. 2 dimostrarono che 129S2/sv topi prestazioni simili al test pesi di C57BL / 6 topi. Femmina C57BL / 6 topi ha segnato circa 15, 129 topi 17, il che significa che potrebbero sollevare circa 5 maglie della catena, circa 70 g. Si tratta di un valore elevato; normalmente 2-3 maglie della catena (punteggio di 6-9, 33-46 g) sono sollevati da topi C57BL / 6 5. Queste differenze sono probabilmente legati a fattori quali la quantità di maneggiare i topi hanno ricevuto ed i dettagli della tecnica dello sperimentatore. Lesioni dell&#39;ippocampo non ha influenzato la forza misurata mediante il test di pesi o il 4 schermata invertita. Prioni (scrapie) topi malati hanno perso di valore sullo schermo invertita da 18 settimane dopo l&#39;infezione 6. Anche se in qualche modo compromessa sulla barra orizzontale e rotarod relativo C57BL / 6 topi, C57BL/10 topi non hanno perso di valore sul sollevamento pesi 5. Topi knockout per tegli KATP canale subunità Kir6.2 non hanno perso di valore sullo schermo invertita o prove di sollevamento pesi, anche se le femmine ottenuto un punteggio superiore rispetto ai maschi in questi ultimi 3. Questo era insolito; normalmente i maschi più pesanti mostrano una maggiore resistenza delle femmine. <img alt="Figura 1" src="/files/ftp_upload/2610/2610fig1.jpg" /> Figura 1. La schermata invertita. <img alt="Figura 2" src="/files/ftp_upload/2610/2610fig2.jpg" /> Figura 2. Chiudere la visualizzazione di un mouse sullo schermo invertita. <img alt="Figura 3" src="/files/ftp_upload/2610/2610fig3.jpg" /> Figura 3. Pesi, che vanno da 20 ga 98 g. <img alt="Figura 4" src="/files/ftp_upload/2610/2610fig4.jpg" /> <strong&gt; Figura 4. Un sollevamento pesi mouse.

Watch this Scientific Journal Video about Measuring the Strength of Mice at JoVE.com

Measuring the Strength of Mice

I deficit di forza muscolare si verificano in molte condizioni cliniche, come la malattia del motoneurone. La schermata invertita e prove di sollevamento pesi qui descritti forza provvedimento nei topi quasi esclusivamente, con minima influenza di fattori quali il coordinamento.

Misurare la forza della Mice

Kondziela7 devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score ...

Research

JoVE Journal

Medicine

54.1K Views.  University of Oxford. I deficit di forza muscolare si verificano in molte condizioni cliniche, come la malattia del motoneurone. La schermata invertita e prove di sollevamento pesi qui descritti forza provvedimento nei topi quasi esclusivamente, con minima influenza di fattori quali il coordinamento.

Video: Measuring the Strength of Mice

Assessing Functional Performance in the Mdx Mouse Model

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder for which no cure is available. Nevertheless, several potential pharmaceutical compounds and gene therapy approaches have progressed into clinical trials. With improvement in muscle function being the most important end point in these trials, a lot of emphasis has been placed on setting up reliable, reproducible, and easy to perform functional tests to pre clinically assess muscle function, strength, condition, and coordination in the mdx mouse model for DMD. Both invasive and noninvasive tests are available. Tests that do not exacerbate the disease can be used to determine the natural history of the disease and the effects of therapeutic interventions (e.g. forelimb grip strength test, two different hanging tests using either a wire or a grid and rotarod running). Alternatively, forced treadmill running can be used to enhance disease progression and/or assess protective effects of therapeutic interventions on disease pathology. We here describe how to perform these most commonly used functional tests in a reliable and reproducible manner. Using these protocols based on standard operating procedures enables comparison of data between different laboratories.

Assessing Functional Performance in the Mdx Mouse Model

The primary outcome measure in clinical trials for neuromuscular disorders is generally improved muscle function. Therefore, assessing the effect of potential therapeutic compounds on muscle performance pre clinically in mouse models is of great importance. We here describe several functional tests to address this.

Valutare prestazioni funzionali nel<em&gt; Mdx</em&gt; Mouse Model

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder for which no cure is available. Nevertheless, several potential ...

Ricerca

Comportamento

Measuring Motor Coordination in Mice

Mice are increasingly being used in behavioral neuroscience, largely replacing rats as the behaviorist's animal of choice. Before aspects of behavior such as emotionality or cognition can be assessed, however, it is vital to determine whether the motor capabilities of e.g. a mutant or lesioned mouse allow such an assessment. Performance on a maze task requiring strength and coordination, such as the Morris water maze, might well be impaired in a mouse by motor, rather than cognitive, impairments, so it is essential to selectively dissect the latter from the former. For example, sensorimotor impairments caused by NMDA antagonists have been shown to impair water maze performance2. 
Motor coordination has traditionally been assessed in mice and rats by the rotarod test, in which the animal is placed on a horizontal rod that rotates about its long axis; the animal must walk forwards to remain upright and not fall off. Both set speed and accelerating versions of the rotarod are available.
The other three tests described in this article (horizontal bar, static rods and parallel bars) all measure coordination on static apparatus. The horizontal bar also requires strength for adequate performance, particularly of the forelimbs as the mouse initially grips the bar just with the front paws. 
Adult rats do not perform well on tests such as the static rods and parallel bars (personal observations); they appear less well coordinated than mice. I have only tested male rats, however, and male mice seem generally less well coordinated than females. Mice appear to have a higher strength:weight ratio than rats; the Latin name, Mus musculus, seems entirely appropriate. The rotarod, the variations of the foot fault test12 or the Catwalk (Noldus)15 apparatus are generally used to assess motor coordination in rats.

Protocols are presented for two established motor coordination tasks, the accelerating rotarod and horizontal bar, also two tests developed in Oxford recently, the static rods and parallel bars. These tests can detect motor impairments potentially of interest in their own right, as well as being possible variables in tests of other areas of behavior.

Misurare Coordinamento motore in Mouse

Mice are increasingly being used in behavioral neuroscience, largely replacing rats as the behaviorist's animal of choice. Before aspects of behavior such ...

Neuroscienze

Battery of Behavioral Tests Assessing General Locomotion, Muscular Strength, and Coordination in Mice

Behavioral testing is used in pre-clinical trials to assess the phenotypic effects and outcomes that a particular disease or treatment has on the animal&#39;s wellbeing and health. There are numerous behavioral tests that may be applied. We selected a test for general locomotion, the open field test (OFT); a test for muscular strength, the mesh test (MT); and a test for coordination, the rotarod test (RR). Testing can be accomplished on a weekly or monthly basis. As a test for general locomotion, the OFT works by objectively monitoring movement parameters while the mouse is in an open field apparatus. The field is generally a 2&#39; x 2&#39; box, and the movements are recorded through laser sensing or through video capture. The mouse is placed in the center of the open field and allowed to move freely for the test. The MT uses the latency for a mouse to fall off an inverted screen as a measure of muscular strength. A mouse is placed on a screen, which is inverted over a clear box, and is timed for their latency to fall. Three trials are performed, with the best of the three trials scored for that day. A score of 60 s is the maximum time a mouse is left inverted. Mice are given a 5-min rest period between mesh test trials. Lastly, an accelerated protocol on the RR assesses motor coordination and endurance. During a trial, a mouse walks on a rotating rod as it increases in speed from 4 rpm to 40 rpm over 5 min. The trial ends when the mouse touches the magnetized pressure sensor upon falling. Each mouse undergoes three trials, and the best trial is scored for that day. This combined behavioral data allows for the global assessment of mobility, coordination, strength, and movement of the test animals. At least two out of the three behavioral testing measures must show improvement for an animal to qualify as having overall improved motor function.

Behavioral testing is used in pre-clinical trials to assess the phenotypic effects of a disease or treatment on an animal's wellbeing. In order to globally assess motor functioning, we selected tests for general locomotion, muscular strength, and coordination: the open field test, the mesh test, and the rotarod test, respectively.

Batteria di comportamentali test valutazione generale locomozione, forza muscolare e coordinazione in topi

Behavioral testing is used in pre-clinical trials to assess the phenotypic effects and outcomes that a particular disease or treatment has on the ...

Systematic Assessment of Well-Being in Mice for Procedures Using General Anesthesia

In keeping with the 3R Principle (Replacement, Reduction, Refinement) developed by Russel and Burch, scientific research should use alternatives to animal experimentation whenever possible. When there is no alternative to animal experimentation, the total number of laboratory animals used should be the minimum needed to obtain valuable data. Moreover, appropriate refinement measures should be applied to minimize pain, suffering, and distress accompanying the experimental procedure. The categories used to classify the degree of pain, suffering, and distress are non-recovery, mild, moderate, or severe (EU Directive 2010/63). To determine which categories apply in individual cases, it is crucial to use scientifically sound tools.
The well-being-assessment protocol presented here is designed for procedures during which general anesthesia is used. The protocol focuses on home cage activity, the Mouse Grimace Scale, and luxury behaviors such as burrowing and nest building behavior as indicators of well-being. It also uses the free exploratory paradigm for trait anxiety-related behavior. Fecal corticosterone metabolites as indicators of acute stress are measured over the 24-h post-anesthetic period.
The protocol provides scientifically solid information on the well-being of mice following general anesthesia. Due to its simplicity, the protocol can easily be adapted and integrated in a planned study. Although it does not provide a scale to classify distress in categories according to the EU Directive 2010/63, it can help researchers estimate the degree of severity of a procedure using scientifically sound data. It provides a way to improve the assessment of well-being in a scientific, animal-centered manner.

We developed a protocol to assess well-being in mice during procedures using general anesthesia. A series of behavioral parameters indicating levels of well-being as well as glucocorticoid metabolites were analyzed. The protocol can serve as a general aid to estimate the degree of severity in a scientific, animal-centered manner.

Valutazione sistematica del benessere nei topi per procedure usando l'anestesia generale

In keeping with the 3R Principle (Replacement, Reduction, Refinement) developed by Russel and Burch, scientific research should use alternatives to animal ...

Measuring Active and Passive Tameness Separately in Mice

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two behavioral components: a reluctance to avoid humans (passive tameness) and a motivation to approach humans (active tameness). To quantify these components in mice, we previously developed behavioral tests for active tameness, passive tameness, and the willingness to stay on a human hand, each designed to be completed within 3 min. The data obtained were used for selective breeding, with a large number of mice analyzed per generation. The active tameness test measures the movement of the mouse toward a human hand and the contact it engages in. The passive tameness test measures the duration of time that a mouse tolerates human touch. In the stay-on-hand test, a mouse is placed on a human hand and touched slowly using the thumb of that hand; the duration of time that the animal remains on the hand is measured. Here, we describe the test set-up and apparatus, explain the procedures, and discuss the appropriate data analysis. Finally, we explain how to interpret the results.

Tameness in animals includes a reduction of avoidance responses to humans (passive tameness) and an increase in active approaches to humans (active tameness). Here, we describe detailed protocols for three behavioral tests (active tameness, passive tameness, and stay-on-hand tests) to separately measure the active and passive tameness of mice.

Attiva e passiva docilità separatamente nei topi di misura

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two ...

Measuring Changes in Tactile Sensitivity in the Hind Paw of Mice Using an Electronic von Frey Apparatus

Measuring inflammation-induced changes in thresholds of hind paw withdrawal from mechanical pressure is a useful technique to assess changes in pain perception in rodents. Withdrawal thresholds can be measured first at baseline and then following drug, venom, injury, allergen,&#160;or otherwise evoked inflammation by applying an accurate force on very specific areas of the skin. An electronic von Frey apparatus allows precise assessment of mouse hind paw withdrawal thresholds that are not limited by the available filament sizes in contrast to classical von Frey measurements. The ease and rapidity of measurements allow for incorporation of assessment of tactile sensitivity outcomes in diverse models of rapid-onset inflammatory and neuropathic pain as multiple measurements can be taken within a short time period. Experimental measurements for individual rodent subjects can be internally controlled against individual baseline responses and exclusion criteria easily established to standardize baseline responses within and across experimental groups. Thus, measurements using an electronic von Frey apparatus represent a useful modification of the well-established classical von Frey filament-based assays for rodent mechanical allodynia that may also be applied to other nonhuman mammalian models.

Electronic von Frey measurements are an effective and improved alternative to classical von Frey filaments, as they allow rapid and precise measurement of changes in rodent mechanical withdrawal thresholds to continuously applied pressure stimuli before and after an inflammatory event.

Measuring inflammation-induced changes in thresholds of hind paw withdrawal from mechanical pressure is a useful technique to assess changes in pain ...

Non-invasive Assessment of Dorsiflexor Muscle Function in Mice

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively affect skeletal muscle. This can result in a loss of muscle mass (atrophy) and/or loss of muscle quality (reduced force per unit of muscle mass), both of which are prevalent in chronic disease, muscle-specific disease, immobilization, and aging (sarcopenia). Skeletal muscle function in animals can be evaluated by a range of different tests. All tests have limitations related to the physiological testing environment, and the selection of a specific test often depends on the nature of the experiments. Here, we describe an in vivo, non-invasive technique involving a helpful and easy assessment of force frequency-curve (FFC) in mice that can be performed on the same animal over time. This permits monitoring of disease progression and/or efficacy&#160;of a potential therapeutic treatment.

Measurement of rodent skeletal muscle contractile function is a useful tool that can be used to track disease progression as well as efficacy of therapeutic intervention. We describe here the non-invasive, in vivo assessment of the dorsiflexor muscles that can be repeated over time in the same mouse.

Valutazione non invasiva della funzione Dorsiflexor muscolare nei topi

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively ...

Medicina

Mechanical Conflict-Avoidance Assay to Measure Pain Behavior in Mice

Pain comprises of both sensory (nociceptive) and affective (unpleasant) dimensions. In preclinical models, pain has traditionally been assessed using reflexive tests that allow inferences regarding pain's nociceptive component but provide little information about the affective or motivational component of pain. Developing tests that capture these components of pain are therefore translationally important. Hence, researchers need to use non-reflexive behavioral assays to study pain perception at that level. Mechanical conflict-avoidance (MCA) is an established voluntary non-reflexive behavior assay, for studying motivational responses to a noxious mechanical stimulus in a 3 chamber paradigm. A change in a mouse's location preference, when faced with competing noxious stimuli, is used to infer the perceived unpleasantness of bright light versus tactile stimulation of the paws. This protocol outlines a modified version of the MCA assay which pain researchers can use to understand affective-motivational responses in a variety of mouse pain models. Though not specifically described here, our example MCA data use the intraplantar complete Freund's adjuvant (CFA), spared nerve injury (SNI), and a fracture/casting model as pain models to illustrate the MCA procedure.

The mechanical conflict-avoidance assay is used as a non-reflexive readout of pain sensitivity in mice which can be used to better understand affective-motivational responses in a variety of mouse pain models.

Saggio meccanico di prevenzione dei conflitti per misurare il comportamento del dolore nei topi

Pain comprises of both sensory (nociceptive) and affective (unpleasant) dimensions. In preclinical models, pain has traditionally been assessed using ...

In vivo Measurement of Knee Extensor Muscle Function in Mice

Skeletal muscle plasticity in response to countless conditions and stimuli mediates concurrent functional adaptation, both negative and positive. In the clinic and the research laboratory, maximal muscular strength is widely measured longitudinally in humans, with knee extensor musculature the most reported functional outcome. Pathology of the knee extensor muscle complex is well documented in aging, orthopedic injury, disease, and disuse; knee extensor strength is closely related to functional capacity and injury risk, underscoring the importance of reliable measurement of knee extensor strength. Repeatable, in vivo assessment of knee extensor strength in pre-clinical rodent studies offers valuable functional endpoints for studies exploring osteoarthritis or knee injury. We report an in vivo and non-invasive protocol to repeatedly measure isometric peak tetanic torque of the knee extensors in mice across time. We demonstrate consistency using this novel method to measure knee extensor strength with repeated assessment in multiple mice producing similar results.

Quantification of knee extensor maximal strength is imperative to understand functional adaptations to aging, disease, injury, and rehabilitation. We present a novel method to repeatedly measure in vivo knee extension isometric peak tetanic torque.

Misurazione in vivo della funzione muscolare estensore del ginocchio nei topi

Skeletal muscle plasticity in response to countless conditions and stimuli mediates concurrent functional adaptation, both negative and positive. In the ...

Biologia

Versatility of Protocols for Resistance Training and Assessment Using Static and Dynamic Ladders in Animal Models

Resistance training is a physical exercise model with profound benefits for health throughout life. The use of resistance exercise animal models is a way to gain insight into the underlying molecular mechanisms that orchestrate these adaptations. The aim of this article is to describe exercise models and training protocols designed for strength training and evaluation of resistance in animal models and provide examples. In this article, strength training and resistance evaluation are based on ladder climbing activity, using static and dynamic ladders. These devices allow a variety of training models as well as provide precise control of the main variables which determine resistance exercise: volume, load, velocity, and frequency. Furthermore, unlike resistance exercise in humans, this is a forced exercise. Thus, aversive stimuli must be avoided in this intervention to preserve animal welfare. Prior to implementation, a detailed design is necessary, along with an acclimatization and learning period. Acclimatization to training devices, such as ladders, weights, and clinical tape, as well as to the manipulations required, is necessary to avoid exercise rejection and to minimize stress. At the same time, the animals are taught to climb up the ladder, not down, to the resting area on the top of the ladder. Resistance evaluation can characterize physical strength and permit adjusting and quantifying the training load and the response to training. Furthermore, different types of strength can be evaluated. Regarding training programs, with appropriate design and device use, they can be sufficiently versatile to modulate different types of strength. Furthermore, they should be flexible enough to be modified depending on the adaptive and behavioral response of the animals or the presence of injuries. In conclusion, resistance training and assessment using ladders and weights are versatile methods in animal research.

The present protocol describes resistance training and testing using static and dynamic ladders in animal models.

Versatilità dei protocolli per l'allenamento e la valutazione della resistenza utilizzando scale statiche e dinamiche in modelli animali

Resistance training is a physical exercise model with profound benefits for health throughout life. The use of resistance exercise animal models is a way ...