A Wellcome Trust para a concessão de financiamento de Acesso Aberto para a Universidade de Oxford. Robert Deacon é um membro do grupo Oxion Oxford, financiado pelo Wellcome Trust concessão WT084655MA.

1. Aparelho Teste de tela invertida de 1,1 Kondziela A tela invertida é um quadrado de 43 centímetros de arame com 12 milímetros quadrados de 1 milímetro de diâmetro do fio (Figura 1). Ele está rodeado por um 4 cm de profundidade perolização de madeira (o que impede o rato ocasional que tenta subam para o outro lado) (Figura 2). 1.2 Pesos teste Sete pesos constituem o aparelho. Cada um consiste de uma bola de emaranhado fino fio de aço inoxidável calibre, um &quot;coletor de escala&quot;, usado para evitar a formação de incrustações de calcário em caldeiras domésticas. O peso deste é pequena (7 g), mas cada colector de escala está ligada a uma série de elos de corrente de aço, cada uma pesando cerca de 13 g. O número de ligações varia de um a sete. Seus pesos são, portanto: 20, 33, 46, 59, 72, 85 e 98 g (Figuras 3 e 4). 2. Próprocedimento Para todos os testes, trazer os ratos para a sala experimental 5-20 min antes de testar para garantir que eles são devidamente acordado. Como regra geral, para permitir a recuperação da força muscular e um retorno aos níveis normais de excitação, descansar os ratos por um retorno à jaula para casa depois de cada teste motor. <ol><li> Teste de tela invertida do Kondziela </li><li> Procedimento: Coloque o mouse no centro da tela de malha de arame, iniciar um stopclock, gire a tela para uma posição invertida mais de 2 segundos, com a cabeça do rato em declínio pela primeira vez. Mantenha a tela constantemente 40-50 cm acima de uma superfície acolchoada. Note-se a altura em que o rato cair, ou removê-lo quando o critério de tempo de 60 segundos é atingido. Tempos maiores critério pode ser útil para algumas experiências. </li><li> Marcando a tela invertida: </li></ol> Caindo entre 1-10 seg = 1 Caindo entre 11-25 seg = 2 Caindo entre 26-60 seg = 3 Caindo depois de 60 seg = 4 Ou, por exemplo, durante 2 min: Caindo entre 1-10 seg = 1 Caindo entre 11-25 seg = 2 Caindo entre 26-60 seg = 3 Caindo entre 61-90 seg = 4 Caindo depois de 90 segundos = 5 3. Pesos de teste Realizar um rato pela base da cauda do meio / e baixá-la para permitir a agarrar o primeiro peso (20 g) que é deitado na bancada do laboratório. Como se apreende o coletor de escala fio com as patas dianteiras, iniciar um relógio de parada e levantar o mouse até o link é claro do banco. A espera por três segundos é o critério. Se o mouse deixa cair o peso em menos de 3 segundos, observe o tempo que ocupou o peso. Descanse o mouse por cerca de 10 seg e experimentá-lo sobre o peso mais uma vez. Se falhar três vezes, que termina o julgamento, eo mouse é atribuído o tempo máximo / peso alcançado. Se ele mantém por 3 segundos, em seguida, experimentá-lo na próxima peso pesado. Se ele levanta esta por 3 segundos, testá-lo na próxima peso mais pesado, depois de tertestado todos os seus cagemates no primeiro peso. Mais uma vez, é dado três chances de manter o peso por 3 seg. A pontuação total final é calculada como o produto do número de elos da cadeia pesada realizada pela completa 3 seg, multiplicado pelo tempo (seg) é realizada. Se o peso pesado é descartada antes de 3 segundos um valor intermediário apropriado é calculado. Assim, um rato segurando um peso de 5-link por 3 segundos, mas incapaz de levantar um peso de 6 link, é atribuída uma pontuação de (5 x 3) = 15. Se ele mantém o peso 6-link para um segundo, ela marca (5 x 3) + (1) = 16. Às vezes, ratos não podem ser adequadamente motivado para prender o aparelho. Isto geralmente ocorre em animais mais velhos. Este problema pode ser minimizado através segurando os murganhos pela cauda durante um longo tempo antes de levá-la a uma distância de aperto de bola de arame.

<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>

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Modelos de mouse de muitas doenças que afetam o sistema motor humano estão continuamente a ser desenvolvido, portanto, bons ensaios de resistência em ratos são essenciais. Exemplos incluem as várias formas de distrofia muscular, doença de Parkinson e coreia de Huntington. Ensaios de resistência também encontrar o uso em modelos de regeneração nervosa após lesão do nervo espinhal ou periférico. Industrial e acidentes automobilísticos continuam a causar deficiência considerável para os seres humanos, mas muito trabalho pré-clínico está atualmente investigando possíveis vias de tratamento com base em fatores de crescimento do nervo. Músculos nunca trabalhar individualmente. Eles são ativados pelo cérebro, local ou reflexos espinhais superiores, através das junções neuromusculares e trabalhar dentro das limitações de outros músculos e do sistema esquelético. Por isso, a complexidade do sistema significa ensaios in vivo de força muscular em que o animal acordado são essenciais para a avaliação do seu estado actual e do effects de quaisquer tratamentos putativo. Ratos instintivamente segurar materiais com uma pegada forte, assim Mus musculus é um animal modelo ideal para avaliar distúrbios de força muscular e possíveis tratamentos.

Para um leigo, a ideia de medir a força em camundongos pode parecer absurdo, até mesmo algo de um oxímoro. No entanto, não é sem razão que a casa / laboratório camundongos são chamados de Mus musculus. Eles possuem uma elevada resistência / peso, maior do que o de ratos. Por exemplo, um rato adulto pode facilmente suportar seu próprio peso corporal, mesmo utilizando apenas parte da frente ou patas traseiras; muito poucos ratos de laboratório adultos podem fazer isso. Ratos estão desempenhando um papel cada vez maior na pesquisa biomédica. Eles podem ser utilizados para modelar muitos distúrbios motores humanos, tanto somáticas e do sistema nervoso central na origem. Os primeiros incluem os mais de trinta formas de distrofia muscular hereditária 1 e miastenia grave, enquanto que os exemplos do último são a esclerose múltipla, a atrofia muscular espinal, doença de Parkinson, doença de Huntington e esclerose lateral amiotrófica. Para todos esses modelos, uma avaliação completa de seus déficits motores deve incluir testes específicosde força.

measuring the strength of mice

Kondziela 7 inventou o teste de tela invertida e publicou-o em 1964. É um teste de força muscular usando todos os quatro membros. A maioria dos mouses normais facilmente pontuação máxima nessa tarefa, é uma tela bruto rápido, mas insensível, eo teste de pesos descrita neste artigo irá fornecer uma medida mais fina da força muscular. Há também várias peças de deformação baseados em bitola de aparelhos disponíveis no mercado que irá fornecer dados mais graduados do que o teste de tela invertida, mas o seu custo pode colocá-los fora do alcance de muitos laboratórios que não são especializados em testes de força. Assim, em 2000, um aparelho simples e barato foi criado pelo autor. Trata-se de uma série de elos da cadeia de comprimento crescente, ligados a um &quot;colecionador de peles&quot; uma bola de arame fino vendido para prevenir calcário acumular-se em áreas de água dura. Uma observação acidental revelou que os ratos poderiam prender estes muito bem, por isso eles provaram ideal como um poin aderênciat para um aparelho de levantamento de peso. Uma falha comum com medidores de força comercial é que o bar ou outro recurso aderência não é fina o suficiente para os ratos para exercer a máxima aderência. Como regra geral, quanto mais fina for a barra de arame ou, melhor um rato pode agarrar com as suas garras pequenas. Este é um teste de resistência puras, embora como em qualquer teste factores de motivação poderiam potencialmente desempenhar um papel. A utilização de colectores de escala, no entanto, parece minimizar problemas motivacionais como a motivação parece ser muito elevada para ratinhos adultos mais jovens normais.

Resultados Esperados Contet et ai. 129S2/sv 2 demonstraram que ratinhos realizada de forma semelhante no teste de pesos para ratinhos C57BL / 6. Feminino camundongos C57BL / 6 marcou cerca de 15, 129 camundongos 17, o que significa que poderia levantar cerca de 5 elos da cadeia, cerca de 70 g. Este é um valor elevado, normalmente 2-3 elos da cadeia (pontuação 6-9, 33-46 g) são levantadas por C57BL / 6 5. Estas diferenças são presumivelmente relacionada a fatores como a quantidade de lidar com os camundongos receberam e os detalhes da técnica do experimentador. As lesões do hipocampo não afetou a força, medida tanto pelo teste de pesos ou 4 tela invertida. Prião (scrapie) ratos doentes foram prejudicados na tela invertida por 18 semanas após a infecção 6. Embora um pouco prejudicada na barra horizontal e rotarod relação a camundongos C57BL / 6, C57BL/10 camundongos não foram prejudicados no levantamento de peso 5. Camundongos knockout para tele canal KATP subunidade Kir6.2 não foram prejudicados na tela invertida ou provas de levantamento de peso, embora as mulheres pontuaram mais do que os homens no último 3. Este foi incomum, normalmente os machos mais pesados ​​exibir mais força do que as fêmeas. <img alt="Figura 1" src="/files/ftp_upload/2610/2610fig1.jpg" /> Figura 1. O ecrã invertido. <img alt="Figura 2" src="/files/ftp_upload/2610/2610fig2.jpg" /> Figura 2. Vista próxima de um mouse na tela invertida. <img alt="Figura 3" src="/files/ftp_upload/2610/2610fig3.jpg" /> Figura 3. Pesos variando de 20 g a 98 g. <img alt="Figura 4" src="/files/ftp_upload/2610/2610fig4.jpg" /> <strong&gt; Figura 4. Um levantamento de peso do mouse.

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

Measuring the Strength of Mice

Déficits na força muscular ocorre em muitas condições clínicas, tais como doença do neurônio motor. A tela invertida e testes de levantamento de peso aqui descrito força medida em camundongos quase que exclusivamente, com mínima influência de fatores como a coordenação.

Medir a força dos ratos

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

53.7K visualizações.  University of Oxford. Déficits na força muscular ocorre em muitas condições clínicas, tais como doença do neurônio motor. A tela invertida e testes de levantamento de peso aqui descrito força medida em camundongos quase que exclusivamente, com mínima influência de fatores como a coordenação.

Vídeo: Measuring the Strength of Mice

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.

Ecocardiografia transtorácica em Ratos

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

Medicina

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.

Teste muscular manual: um método de medir a força muscular Extremidade Aplicada à pacientes criticamente enfermos

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.

Transplante ortotópico de aorta em camundongos para o Estudo da Doença 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.

Medição da aorta ascendente Rigidez<em&gt; In Vivo</em&gt; Em ratos usando ultra-som

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

Adapted Resistance Training Improves Strength in Eight Weeks in Individuals with Multiple Sclerosis

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can improve strength in individuals with MS, however; it remains unclear the duration of RST that is needed to make strength gains and how to adapt hip strengthening exercises for individuals of varying strength using only resistance bands. This paper describes the methodology to set up and implement an adapted resistance strength training program, using resistance bands, for individuals with MS. Directions for pre- and post-strength tests to evaluate efficacy of the strength-training program are included. Safety features and detailed instructions outline the weekly program content and progression. Current evidence is presented showing that significant strength gains can be made within 8 weeks of starting a RST program. Evidence is also presented showing that resistance strength training can be successfully adapted for individuals with MS of varying strength with little equipment.

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis. Isolated muscle strengthening is a useful method to target specific weaknesses. This protocol describes a progressive resistance-training program using exercise bands to increase hip muscle strength.

Treinamento da resistência adaptada melhora a força em oito semanas em indivíduos com esclerose múltipla

Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis (MS). It is known that resistance strength training (RST) can ...

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).

Melhorando a Força, o Poder, a Capacidade Aeróbia Muscular e a Tolerância à Glucose através do Treinamento de Força Progressiva de Curto Prazo entre Pessoas Idosas

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 o efeito de produtos químicos sobre o crescimento e a reprodução de Caenorhabditis elegans

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

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.

Coleta de sangue por punção da veia subclávia em camundongos

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

Repeated Orotracheal Intubation in Mice

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ventral neck for direct confirmation of cannula placement in the trachea. The relative difficulty or the tissue trauma induced to the subject by such procedures can be an impediment to an investigator&#8217;s ability to perform longitudinal studies. This article illustrates a technique in which physical manipulation of the mouse following the use of a depilatory to remove hair from the ventral neck permits transcutaneous visualization of the trachea for orotracheal intubation regardless of degree of skin pigmentation. This method is innocuous to the subject and easily achieved with a limited understanding of murine anatomy. This refined approach facilitates repeated intubation, which may be necessary for monitoring progression of disease or instillation of treatments. Using this method may result in a reduction of the number of animals and technical skill required to measure lung function in mouse models of respiratory disease.

The goal of this article is to describe a refined method of intubation of the laboratory mouse. The method is noninvasive and, therefore, ideal for studies that require serial monitoring of respiratory function and/or instillation of treatments into the lung.

Intubação Orotraqueal Repetida em Camundongos

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Administração Intratraqueal de Formulação de Pó Seco em Camundongos

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...