El Wellcome Trust para proporcionar financiación de Acceso Abierto a la Universidad de Oxford. Robert Diácono es un miembro del grupo OXION Oxford, financiado por el Wellcome Trust subvención WT084655MA.

1. Aparato Prueba de pantalla invertida de 1,1 Kondziela La pantalla invertida es de 43 cm cuadrados de malla de alambre que consiste en 12 cuadrados de 1 mm de alambre de diámetro mm (Figura 1). Está rodeado por un cm abalorios de madera profundo 4 (que evita el ratón ocasional que intenta de escalada en el otro lado) (Figura 2). 1.2 Pesas Siete pesos constituyen el aparato. Cada uno consiste en una bola de hilo enredado calibre fino de acero inoxidable, un &quot;cobrador de escala&quot;, como se usa para prevenir la formación de piedra caliza escala en calderas domésticas. El peso de este es pequeño (7 g), pero cada colector escala está unido a una serie de eslabones de cadena de acero, cada uno de un peso aproximado de 13 g. El número de enlaces va de uno a siete. Sus pesos son por lo tanto: 20, 33, 46, 59, 72, 85 y 98 g (Figuras 3 y 4). 2. Proprocedimiento Para todas las pruebas, poner a los ratones a la sala experimental 5-20 min antes de la prueba para asegurarse de que estén bien despiertos. Como regla general, para permitir la recuperación de la fuerza muscular y el retorno a los niveles normales de la excitación, el resto de los ratones por un retorno a la jaula después de cada prueba del motor. <ol><li> Prueba de pantalla invertida de Kondziela </li><li> Procedimiento: Coloque el ratón en el centro de la pantalla de malla de alambre, iniciar un cronómetro, gire la pantalla a una posición invertida durante 2 segundos, con la cabeza del ratón de la disminución de primera. Mantenga la pantalla de manera constante 40-50 cm sobre una superficie acolchada. Tenga en cuenta el momento en que el ratón se cae, o retirarlo cuando se alcanza el criterio de tiempo de 60 seg. Criterio veces más largos pueden ser útiles para algunos experimentos. </li><li> Clasificación de la pantalla invertida: </li></ol> La caída de entre 1 a 10 seg = 1 La caída de entre 11 a 25 segundos = 2 La caída de entre 26 a 60 segundos = 3 La caída después de 60 segundos = 4 O, por ejemplo, durante 2 minutos: La caída de entre 1 a 10 seg = 1 La caída de entre 11 a 25 segundos = 2 La caída de entre 26 a 60 segundos = 3 La caída de entre 61 a 90 segundos = 4 La caída después de 90 segundos = 5 3. Los pesos de prueba Mantenga el ratón por la base central / de la cola y lo baja para que pueda captar el primer peso (20 g), que está tumbado en la mesa de laboratorio. Como se agarra el colector escala de alambre con sus patas delanteras, iniciar un cronómetro y elevar el ratón hasta que el enlace quede fuera del banco. A espera de los tres segundos es el criterio. Si el ratón deja caer el peso en menos de 3 segundos, tenga en cuenta el tiempo que se mantuvo el peso. Apoye el mouse por alrededor de 10 segundos y probarlo en el peso de nuevo. Si falla tres veces, que termina el juicio, y el ratón se asigna el tiempo máximo / peso conseguida. Si se mantiene durante 3 segundos y luego probarlo en el siguiente peso más pesado. Si se levanta este durante 3 segundos, prueba en la siguiente peso pesado, después de haberprobado todos sus compañeros de jaula en el primer peso. Una vez más, se le da tres oportunidades para mantener el peso durante 3 segundos. Una puntuación total final se calcula como el producto del número de eslabones de la cadena pesada se celebró por completo 3 segundos, multiplicado por el tiempo (segundos) que se lleva a cabo. Si el peso más pesado se cae antes de 3 segundos se calcula un valor intermedio adecuado. Así, un ratón que sostiene un peso de 5 enlaces por 3 segundos, pero incapaz de levantar un peso 6-link, se le asigna una puntuación de (5 x 3) = 15. Si se mantiene el peso 6-link por 1 segundo, se apunta (5 x 3) + (1) = 16. A veces, los ratones no pueden ser debidamente motivados para agarrar el aparato. Esto ocurre generalmente en los animales más viejos. Este problema puede ser minimizado mediante la celebración de los ratones por la cola durante un tiempo más largo antes de llevarlo dentro de la distancia de agarre de la bola de alambre.

<ol>
	<li>Bulfield, G., Siller, W. G., Wight, P. A., Moore, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=K.J.X+chromosome-linked+muscular+dystrophy+(mdx)+in+the+mouse.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=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 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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+phenotyping+of+mice+lacking+the+KATP+channel+subunit+Kir6.2.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hippocampal+cytotoxic+lesion+effects+on+species-typical+behaviors+in+mice.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+the+behavior+of+C57BL/6+and+C57BL/10+mice.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+behavioural+changes+in+scrapie-affected+mice+and+the+influence+of+dapsone.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eine+neue+method+zur+messung+der+muskularen+relaxation+bei+weissen+mausen.">Eine neue method zur messung der muskularen relaxation bei weissen mausen.</a> Arch. Int. Pharmacodyn. 152, 277-284 (1964).</li></ol>

No hay conflictos de interés declarado.

Se están desarrollando modelos de ratón de las muchas enfermedades que afectan a los sistemas de motor humanos, por lo tanto, buenos ensayos de resistencia en los ratones son esenciales. Algunos ejemplos son las muchas formas de distrofia muscular, enfermedad de Parkinson y la corea de Huntington. Ensayos de fuerza también encuentran su uso en modelos de regeneración de los nervios después de una lesión del nervio espinal o periférico. Industrial y accidentes automovilísticos siguen causando considerable discapacidad a los humanos, pero mucho trabajo preclínico está investigando actualmente las posibles vías de trato basadas en factores de crecimiento nervioso. Los músculos no trabajan individualmente. Son activados por el cerebro, local o mayores reflejos espinales, a través de las uniones neuromusculares y trabajar dentro de las limitaciones de otros músculos y el sistema esquelético. Por lo tanto, la complejidad del sistema significa en ensayos in vivo de la fuerza muscular en el animal despierto son esenciales en la evaluación de su estado actual y el efects de cualquier tratamiento putativo. Ratones instintivamente se aferran a materiales con un agarre fuerte, por lo tanto Mus musculus es un animal modelo ideal en el que para evaluar los trastornos de la fuerza muscular y posibles tratamientos.

Para una persona común, la idea de medir la fuerza en ratones podría parecer absurdo, incluso algo así como un oxímoron. Sin embargo, no es sin razón que ratones de casa / laboratorio se nombran Mus musculus. De hecho, tienen una muy alta resistencia / peso, mayor que el de las ratas. Por ejemplo, los ratones adultos pueden apoyar fácilmente su propio peso corporal, incluso utilizando sólo un primer plano o las patas traseras, muy pocas ratas de laboratorio adultos pueden hacer esto. Los ratones están desempeñando un papel cada vez más importante en la investigación biomédica. Pueden ser utilizados para modelar muchos trastornos motores humanos, tanto somáticos y del sistema nervioso central en origen. Los primeros incluyen los más de treinta formas de distrofia muscular heredada 1 y la miastenia grave, mientras que los ejemplos de estos últimos son la esclerosis múltiple, atrofia muscular espinal, la enfermedad de Parkinson, enfermedad de Huntington y la esclerosis lateral amiotrófica. Para todos estos modelos, una evaluación completa de sus déficits motores debe incluir pruebas específicasde fuerza.

measuring the strength of mice

Kondziela 7 ideó la prueba de pantalla invertida y lo publicó en 1964. Es una prueba de la fuerza muscular usando las cuatro extremidades. Mayoría de los ratones normales con facilidad puntuación máxima en esta tarea, sino que es una pantalla bruta rápido pero insensible, y la prueba de peso se describe en este artículo se proporcionará una medida más fina de la fuerza muscular. También hay varias piezas de calibre basados ​​en la cepa de aparatos disponibles en el mercado que proporcionen datos más graduales que la prueba de pantalla invertida, pero su costo puede ponerlos fuera del alcance de muchos laboratorios que no se especializan en pruebas de fuerza. De ahí que en 2000 un aparato barato y sencillo fue ideado por el autor. Se compone de una serie de eslabones de cadena de longitud creciente, que se adjunta a un &quot;colector de piel&quot; una bola de malla de alambre fino se vende para la prevención de la acumulación de cal en zonas de agua dura. Una observación accidental reveló que los ratones podían agarrar estas muy bien, por lo que resultó ser ideal como poin gript para un aparato de levantamiento de pesas. Un fallo común con medidores de comerciales es que la barra o cualquier otro elemento de agarre no es lo suficientemente delgada como para los ratones de ejercer un control máximo. Como regla general, el más fino es el alambre o barra, la mejor un ratón puede agarrar con sus pequeñas garras. Esta es una prueba pura de la fuerza, a pesar de que para cualquier prueba de factores motivacionales potencialmente podrían desempeñar un papel. El uso de colectores de escala, sin embargo, parece minimizar problemas de motivación como la motivación parece ser muy alta para la mayoría de los ratones adultos jóvenes normales.

Resultados Esperados Contet et al. 2 demostraron que los ratones 129S2/sv realizaron de manera similar en la prueba de pesos a ratones C57BL / 6. Mujeres C57BL / 6 ratones obtuvo aproximadamente 15, 129 17 ratones, lo que significa que podrían levantar aproximadamente 5 eslabones de la cadena, en torno a 70 g. Esto es un gran valor, normalmente 2-3 eslabones de la cadena (puntuación 6-9, 33-46 g) se levantan por ratones C57BL / 6 5. Estas diferencias están probablemente relacionados con factores tales como la cantidad de manejo han recibido los ratones y los detalles de la técnica del experimentador. Las lesiones del hipocampo no afectaron a la fuerza tal como se mide ya sea por la prueba de pesos o la pantalla invertida 4. Priones (scrapie) ratones enfermos fueron perjudicados en la pantalla invertida por 18 semanas después de la infección 6. Aunque un poco deteriorado en la barra horizontal y rotarod relación con los ratones C57BL / 6, C57BL/10 ratones no fueron dañados en el levantamiento de pesas 5. Ratones knockout para tque KATP canal subunidad Kir6.2 no se deterioraron en la pantalla invertida o pruebas de levantamiento de pesas, aunque las mujeres puntuaron más alto que los hombres en estos últimos 3. Esto era inusual, normalmente los machos más pesados ​​muestran una mayor resistencia que las hembras. <img alt="Figura 1" src="/files/ftp_upload/2610/2610fig1.jpg" /> Figura 1. La pantalla invertida. <img alt="La figura 2" src="/files/ftp_upload/2610/2610fig2.jpg" /> Figura 2. Vista cercana de un ratón en la pantalla invertida. <img alt="Figura 3" src="/files/ftp_upload/2610/2610fig3.jpg" /> Figura 3. Pesos, que van desde 20 g hasta 98 g. <img alt="Figura 4" src="/files/ftp_upload/2610/2610fig4.jpg" /> <strong&gt; Figura 4. A pesas ratón.

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

Measuring the Strength of Mice

Los déficits en la fuerza muscular se producen en muchas condiciones clínicas tales como enfermedad de la motoneurona. La pantalla invertida y pruebas de levantamiento de pesas describen aquí la fuerza medida en ratones casi exclusivamente, con una influencia mínima de factores tales como la coordinación.

La medición de la fuerza de ratones

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 ...

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

53.9K vistas.  University of Oxford. Los déficits en la fuerza muscular se producen en muchas condiciones clínicas tales como enfermedad de la motoneurona. La pantalla invertida y pruebas de levantamiento de pesas describen aquí la fuerza medida en ratones casi exclusivamente, con una influencia mínima de factores tales como la coordinación.

Video: Measuring the Strength of Mice

Programmed Electrical Stimulation in Mice

Genetically-modified mice have emerged as a preferable animal model to study the molecular mechanisms underlying conduction abnormalities, atrial and ventricular arrhythmias, and sudden cardiac death.1 Intracardiac pacing studies can be performed in mice using a 1.1F octapolar catheter inserted into the jugular vein, and advanced into the right atrium and ventricle. Here, we illustrate the steps involved in performing programmed electrical stimulation in mice. Surface ECG and intracardiac electrograms are recorded simultaneously in the atria, atrioventricular junction, and ventricular myocardium, whereas intracardiac pacing of the atrium is performed using an external stimulator. Thus, programmed electrical stimulation in mice provides unique opportunities to explore molecular mechanisms underlying conduction defects and cardiac arrhythmias.

Programmed electrical stimulation provides the ability to determine conduction properties of the heart, and the possibility to induce and terminate cardiac arrhythmias using various pacing protocols. Using a transvenous catheter, intracardiac electrogram recordings can be obtained in mice following programmed electrical stimulation protocols to identify arrhythmogenic substrates.

La estimulación eléctrica programada en ratones

Genetically-modified mice have emerged as a preferable animal model to study the molecular mechanisms underlying conduction abnormalities, atrial and ...

Investigación

Medicina

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,6 whereas TDI is used to measure the velocity of myocardial motion.7 Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.

Transthoracic echocardiography offers a noninvasive method for the evaluation of cardiac function in mice. A combination of ultrasound and Doppler imaging modalities can be used to obtain dimensional measurements of the heart and intracardiac blood flow, which together provide an assessment of cardiac systolic and diastolic performance.

Ecocardiografía transtorácica en ratones

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene ...

Manual Muscle Testing:  A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge.1-6 Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. 7, 8 
This video demonstrates a protocol for MMT, which has been taught to &ge;43 research staff who have performed &gt;800 assessments on &gt;280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale.7,9-11 Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. 1,2.

Survivors of acute respiratory distress syndrome (ARDS) and critical illness frequently develop long-lasting muscle weakness. Manual muscle testing (MMT) is a standardized clinical examination commonly used to measure strength of peripheral skeletal muscle groups. This video demonstrates MMT using the 6-point Medical Research Council scale.

Pruebas musculares manuales: un método para medir fuerza de las extremidades muscular aplicada a los pacientes críticos

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, ...

Orthotopic Aortic Transplantation in Mice for the Study of Vascular Disease

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. This is largely true, but there are a number of important principles that can reduce the difficulty of these procedures and enhance reproducibility. Orthotopic aortic transplantation is an excellent procedure in which to learn these principles because it involves only two end-to-end anastomoses, but requires good suturing technique and handling of the vessels for consistent success. This procedure begins with the procurement of a length of abdominal aorta from a donor animal, followed by division of the native aorta in the recipient. The procured aorta is then placed between the divided ends of the recipient aorta and sutured into place using end-to-end anastomoses. To accomplish this objective successfully requires a high degree of concentration, good tools, a steady hand, and an appreciation of how easily the vasculature of a mouse can be damaged, resulting in thrombosis. Learning these important principles is what occupies most of the beginner's time when learning microsurgery in small rodents. Throughout this protocol, we refer to these important points. This model can be used to study vascular disease in a variety of different experimental systems1-8. In the context shown here, it is most often used for the study of post-transplant vascular disease, a common long-term complication of solid organ transplantation in which intimal hyperplasia occurs within the allograft. The primary advantage of the model is that it facilitates quantitative morphometric analyses and the transplanted vessel lies contiguous to the endogenous vessel, which can serve as an additional control9. The technique shown here is most often used for mice weighing 18-25 grams. We have accumulated most of our experience using the C57BL/6J, BALB/cJ, and C3H/HeJ strains.

We describe a technique in which a section of the abdominal aorta from a mouse is transplanted orthotopically to just below the renal arteries in an allogeneic or syngeneic recipient. This technique can be useful in studies in which transplantation of large arteries of uniform size is deemed advantageous.

El trasplante ortotópico aórtica en los ratones para el Estudio de la Enfermedad Vascular

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. ...

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound and aortic blood pressure is measured invasively with a solid-state pressure catheter. Blood pressure is raised then lowered incrementally by intravenous infusion of vasoactive drugs phenylephrine and sodium nitroprusside. Aortic diameter is measured for each pressure step to characterize the pressure-diameter relationship of the ascending aorta. Stiffness indices derived from the pressure-diameter relationship can be calculated from the data collected. Calculation of arterial compliance is described in this protocol.
This technique can be used to investigate mechanisms underlying increased aortic stiffness associated with cardiovascular disease and aging. The technique produces a physiologically relevant measure of stiffness compared to ex vivo approaches because physiological influences on aortic stiffness are incorporated in the measurement. The primary limitation of this technique is the measurement error introduced from the movement of the aorta during the cardiac cycle. This motion can be compensated by adjusting the location of the probe with the aortic movement as well as making multiple measurements of the aortic pressure-diameter relationship and expanding the experimental group size.

Measuring Ascending Aortic Stiffness In Vivo in Mice Using Ultrasound

We describe a technique for measuring aortic stiffness from its pressure-diameter relationship in vivo in mice. Aortic diameter is recorded by ultrasound and aortic pressure is measured invasively with a solid-state pressure catheter. Blood pressure is changed incrementally and the resulting diameter is measured.

Medición ascendente aórtica Rigidez<em&gt; En Vivo</em&gt; En ratones usando ultrasonido

We present a protocol for measuring in vivo aortic stiffness in mice using high-resolution ultrasound imaging. Aortic diameter is measured by ultrasound ...

Minimally Invasive Transverse Aortic Constriction in Mice

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard open-chest transverse aortic constriction (TAC). Although transverse aortic constriction is a highly functional method for the induction of high pressure in the left ventricle, it is a more difficult and lengthy procedure due to its use of artificial ventilation with tracheal intubation. TAC is oftentimes also less survivable, as the newer method, MTAC, neither requires the cutting of the ribs and intercostal muscles nor tracheal intubation with a ventilation setup. In MTAC, as opposed to a thoracotomy to access to the chest cavity, the aortic arch is reached through a midline incision in the anterior neck. The thyroid is pulled back to reveal the sternal notch. The sternum is subsequently cut down to the second rib level, and the aortic arch is reached simply by separating the connective tissues and thymus. From there, a suture can be wrapped around the arch and tied with a spacer, and then the sternal cut and skin can be closed. MTAC is a much faster and less invasive way to induce left ventricular hypertension and enables the possibility for high-throughput studies. The success of the constriction can be verified using high-frequency trans-thoracic echocardiography, particularly color Doppler and pulsed-wave Doppler, to determine the flow velocities of the aortic arch and left and right carotid arteries, the dimension of the blood vessels, and the left ventricular function and morphology. A successful constriction will also trigger significant histopathological changes, such as cardiac muscle cell hypertrophy with interstitial and perivascular fibrosis. Here, the procedure of MTAC is described, demonstrating how the resulting flow changes in the carotid arteries can be examined with echocardiography, gross morphology, and histopathological changes in the heart.

Minimally invasive transverse aortic constriction (MTAC) conserves the essentials of regular transverse aortic constriction (TAC) while eliminating the use of a ventilator with tracheal intubation. It proves to be a highly desirable method for high-throughput studies on left ventricular overload, particularly in translational studies.

La constricción aórtica mínimamente invasiva transversal en ratones

Minimally invasive transverse aortic constriction (MTAC) is a more desirable method for the constriction of the transverse aorta in mice than standard ...

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People

This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in elderly people performing short-term resistance training (RET). Supervised progressive resistance training for 1 h three times a week over 8 weeks was performed by RET participants (71&#177;1 years, range 65-80). Compared to a control group without training, the RET showed improvements on the measures used to indicate strength, power, glucose tolerance, and several parameters of muscle aerobic capacity. Strength training was performed in a gym with only robust fitness equipment. An isokinetic dynamometer for knee extensor strength permitted the measurement of concentric, eccentric, and static strength, which increased for the RET group (8-12% post- versus pre-test). The power (rate of force development, RFD) at the initial 0-30 ms also showed an increase for the RET group (52%). A glucose tolerance test with frequent blood glucose measurements showed improvements only for the RET group in terms of blood glucose values after 2 h (14%) and the area under the curve (21%). The blood lipid profile also improved (8%). From muscle biopsy samples prepared using histochemistry, the amount of fiber type IIa increased, and a trend towards a decrease in IIx in the RET group reflected a change to a more oxidative profile in terms of fiber composition. Western blot (to determine the protein content related to the signaling for muscle protein synthesis) showed a rise of 69% in both Akt and mTOR in the RET group; this also showed an increase in mitochondrial proteins for OXPHOS complex II and citrate synthase (both ~30%) and for complex IV (90%), in only the RET group. We demonstrate that this type of progressive resistance training offers various improvements (e.g., strength, power, aerobic capacity, glucose tolerance, and plasma lipid profile).

The effect of short-term resistance training on elderly people was investigated through the simultaneous use of several methods. Compared to a control group, many improvements were seen, including on muscle aerobic capacity, glucose tolerance, strength, power, and muscle quality (i.e., protein involved in cell signaling and muscle fiber type composition).

Mejora de la Fuerza, Potencia, Capacidad Aeróbica Muscular y Tolerancia a la Glucosa a través del Entrenamiento de Fuerza Progresiva a Corto Plazo entre Ancianos

This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in ...

Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans

Toxicological evaluation is crucial for understanding the effects of chemicals on living organisms in basic and applied biological science fields. A non-mammalian soil round worm, Caenorhabditis elegans, is a valuable model organism for toxicology studies due to its convenience and lack of animal ethics issues compared with mammalian animal systems. In this protocol, a detailed procedure of toxicological evaluation of chemicals in C. elegans is described. A clinical anticancer drug, etoposide, which targets human topoisomerase II and inhibits DNA replication of human cancer cells, was selected as a model testing chemical. Age-synchronized C. elegans eggs were exposed to either dimethyl sulfoxide (DMSO) or etoposide, and then the growth of C. elegans was monitored every day for 4 days by the stereo microscope observation. The total number of eggs laid from C. elegans treated with DMSO or etoposide was also counted by using the stereo microscope. Etoposide treatment significantly affected the growth and reproduction of C. elegans. By comparison of the total number of eggs laid from worms with different treatment periods of chemicals, it can be decided that the reproductive toxicity of chemicals on C. elegans reproduction is reversible or irreversible. These protocols may be helpful for both the development of various drugs and risk assessment of environmental toxicants.

Measuring the Effect of Chemicals on the Growth and Reproduction of Caenorhabditis elegans

A basic protocol to evaluate the toxicity of chemicals in a model animal, Caenorhabditis elegans, is described. The method is convenient and useful for the development of pharmaceuticals as well as for the risk assessment of various environmental pollutants.

Medir el efecto de productos químicos sobre el crecimiento y reproducción de Caenorhabditis elegans

Toxicological evaluation is crucial for understanding the effects of chemicals on living organisms in basic and applied biological science fields. A ...

Assessment and Characterization of Hyaloid Vessels in Mice

In the eye, the embryonic hyaloid vessels nourish the developing lens and retina and regress when the retinal vessels develop. Persistent or failed regression of hyaloid vessels can be seen in diseases such as persistent hyperplastic primary vitreous (PHPV), leading to an obstructed light path and impaired visual function. Understanding the mechanisms underlying the hyaloid vessel regression may lead to new molecular insights into the vascular regression process and potential new ways to manage diseases with persistent hyaloid vessels. Here we describe the procedures for imaging hyaloid in live mice with optical coherence tomography (OCT) and fundus fluorescein angiography (FFA) and a detailed technical protocol of isolating and flat-mounting hyaloid ex vivo for quantitative analysis. Low-density lipoprotein receptor-related protein 5 (LRP5) knockout mice were used as an experimental model of persistent hyaloid vessels, to illustrate the techniques. Together, these techniques may facilitate a thorough assessment of hyaloid vessels as an experimental model of vascular regression and studies on the mechanism of persistent hyaloid vessels.

This protocol describes both in vivo and ex vivo methods to fully visualize and characterize hyaloid vessels, a model of vascular regression in mouse eyes, using optical coherence tomography and fundus fluorescein angiography for the live imaging and ex vivo isolation and subsequent flat mount of hyaloid for quantitative analysis.

Evaluación y caracterización de recipientes hialoides en ratones

In the eye, the embryonic hyaloid vessels nourish the developing lens and retina and regress when the retinal vessels develop. Persistent or failed ...

Blood Collection Through Subclavian Vein Puncture in Mice

The mouse is the foremost mammalian model for studying human disease and human health. However, blood sample collection from mice is challenging in research work. Tail blood collection is a popular method when a small amount of blood sample is needed. Orbital artery could be considered if a large amount of blood is needed but this blood collection method has ethical issues. Formerly, we demonstrated the feasibility and safety of blood sample collection through subclavian vein puncture in rats, and here we investigate whether this method could be used in mice. We report that this method is safe and practical for blood collection in mice. Blood collection through the subclavian vein puncture in mice can be a convenient method in daily research works.

Here, we present a protocol to take blood samples from the subclavian vein of mice.

Recolección de sangre a través de punción venosa Subclaviana en ratones

The mouse is the foremost mammalian model for studying human disease and human health. However, blood sample collection from mice is challenging in ...