Reconocemos la asistencia en un crack de Annie B. Kristensen, Elisabeth V. Andersen, Belinda B. Bringtoft y los cuidadores de animales en el Departamento de Medicina Experimental, Frederiksberg Campus de la Facultad de Salud y Ciencias Médicas de la Universidad de Copenhague, Dinamarca. Jacob Lønholdt se dio las gracias por su excelente asistencia técnica en la filmación de los procedimientos. Este estudio fue apoyado en parte por el Centro LifePharm en vivo y Farmacología de la Universidad de Copenhague.

Los procedimientos que se muestran se realizaron de acuerdo a los protocolos aprobados por el danés Experimentación Animal Inspección, dependiente del Ministerio de Alimentación, Agricultura y Pesca. 1. Sangre de muestreo desde el lateral safena o tarsal Vein <ol><li> Lleve a cabo este procedimiento sin anestesia y la ayuda de un investigador, que maneja el conejillo de indias, y una recogida de la muestra. </li><li> Afeitarse la región tarsal de la pata trasera con una rasuradora eléctrica hasta que las venas son visibles. Asegúrese de que el área es lo suficientemente grande para evitar la piel interferir con el sitio de punción. </li><li> Coloque las patas traseras en un baño de agua tibia y frote suavemente la pierna, por lo que las venas más dilatada y evidente. </li><li> Limpie la pierna con una toalla limpia y desinfecta la zona de punción con una gasa o un hisopo de algodón humedecido con alcohol al 70%. </li><li> Prohibir al conejillo de Indias y extender la pierna trasera hacia abajo mientras se aplica una presión suave inmediatamente por encima de la rodilla t conjuntao proporcionar la estasis. </li><li> La punción de la vena con una aguja 21 G o lanceta. Recoger la sangre por ejemplo., Mediante el uso de un tubo de recogida o capilar. Manipular suavemente la pierna para ayudar al flujo sanguíneo. </li><li> Soltar la estasis, una vez que se ha obtenido la muestra. Aplicar un trozo de gasa o algodón lana con una suave presión sobre el área hasta que el sangrado se ha detenido. </li><li> Volver al animal a su jaula y el monitor durante 5-10 minutos para asegurar la hemostasia. </li></ol> 2. de muestra de sangre de la vena de la oreja <ol><li> Realice este procedimiento sin anestesia ya sea solo o, preferiblemente, con la ayuda de un colega. </li><li> Desinfectar la superficie dorsal de la oreja con una gasa o un hisopo de algodón humedecido con alcohol al 70%. </li><li> Aplique una leve presión sobre la base de la oreja para proporcionar la estasis. </li><li> La punción de la vena con una aguja 21 G o lanceta, y recoger la sangre. </li><li> Suelte la estasis, una vez obtenida la muestra, Aplicar un trozo de gasa o un algodón con gepresión ntle al sitio de punción hasta que el sangrado se ha detenido. </li><li> Volver al animal a su jaula y el monitor durante 5-10 minutos para asegurar la hemostasia. </li></ol> 3. Sangre de muestreo de la vena yugular <ol><li> Esta operación se realizará mediante la ayuda de un investigador adicional; que maneja el conejillo de indias y una recogida de la muestra. </li><li> Anestesiar el conejillo de indias con un anestésico adecuado para toda la duración de este procedimiento. Una mezcla de tiletamina (0,93 mg / kg), zolazepam (0,93 mg / kg), xilazina (1,49 mg / kg) y butorfanol (0,06 mg / kg) puede ser utilizado. </li><li> Coloque el conejillo de indias anestesiados en su parte posterior y retraer con suavidad las patas delanteras en sentido caudal. </li><li> Afeitado y desinfectar (por ejemplo., Con 70% de alcohol) la parte ventral del cuello. </li><li> Escudo la jeringa con heparina o EDTA antes del muestreo con el fin de reducir el riesgo de coagulación. </li><li> Palpar la clavícula e inserte un 25 G (o 23 G) de aguja montada en una jeringa de 1 ml apmadamente 1 cm lateral a la línea media a nivel de la articulación del hombro. Conservar la jeringa en un ángulo ligeramente hacia arriba y medial mientras se aplica una ligera presión negativa. Evitar daños en las estructuras subyacentes como la vena yugular se encuentra bastante superficial. Incline el cuello del cuy ligeramente hacia atrás para proporcionar un aumento de la estasis de la vena. </li><li> Suelte las patas delanteras cuando se obtiene la muestra de sangre, y aliviar la estasis antes se retrae la aguja. Use un pedazo seco de gasa o un algodón para aplicar una suave presión sobre el sitio de la punción. </li><li> Volver al animal a una jaula de recuperación y seguimiento para asegurar la hemostasia y la recuperación de la anestesia. </li></ol>

<ol>
	<li>DeOgburn, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+increased+dietary+cholesterol+with+carbohydrate+restriction+on+hepatic+lipid+metabolism+in+Guinea+pigs.">Effects of increased dietary cholesterol with carbohydrate restriction on hepatic lipid metabolism in Guinea pigs.</a> Comp.Med. 62 (2), 109-115 (2012).</li><li>Fernandez, M., Volek, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Guinea+pigs+a+suitable+animal+model+to+study+lipoprotein+metabolism,+atherosclerosis+and+inflammation.">Guinea pigs a suitable animal model to study lipoprotein metabolism, atherosclerosis and inflammation.</a> Nutr Metab (Lond). 3 (17), (2006).</li><li>Frikke-Schmidt, H., Tveden-Nyborg, P., Birck, M. M., Lykkesfeldt, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+dietary+fat+and+cholesterol+exacerbates+chronic+vitamin+C+deficiency+in+guinea+pigs.">High dietary fat and cholesterol exacerbates chronic vitamin C deficiency in guinea pigs.</a> Br J Nutr. 105 (1), 54-61 (2011).</li><li>Hem, A., Smith, A. J., Solberg, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Saphenous+vein+puncture+for+blood+sampling+of+the+mouse,+rat,+hamster,+gerbil,+guinea+pig,+ferret+and+mink.">Saphenous vein puncture for blood sampling of the mouse, rat, hamster, gerbil, guinea pig, ferret and mink.</a> Lab Anim. 32 (4), 364-368 (1998).</li><li>Parasuraman, S., Raveendran, R., Kesavan, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+sample+collection+in+small+laboratory+animals.">Blood sample collection in small laboratory animals.</a> J Pharmacol Pharmacother. 1 (2), 87-93 (2010).</li><li>Guillen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FELASA+guidelines+and+recommendations.">FELASA guidelines and recommendations.</a> J Am Assoc Lab Anim Sci. 51 (3), 311-321 (2012).</li><li>Ye, P., Cheah, I. K., Halliwell, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+fat+diets+and+pathology+in+the+guinea+pig+Atherosclerosis+or+liver+damage.">High fat diets and pathology in the guinea pig Atherosclerosis or liver damage.</a> Biochim Biophys Acta. 1832 (2), 355-364 (2013).</li><li>Tveden-Nyborg, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maternal+vitamin+C+deficiency+during+pregnancy+persistently+impairs+hippocampal+neurogenesis+in+offspring+of+guinea+pigs.">Maternal vitamin C deficiency during pregnancy persistently impairs hippocampal neurogenesis in offspring of guinea pigs.</a> PLoS One. 7 (10), 12-18391 (2012).</li><li>Schjoldager, J. G., Tveden-Nyborg, P., Lykkesfeldt, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+maternal+vitamin+C+deficiency+overrides+preferential+fetal+ascorbate+transport+but+does+not+influence+perinatal+survival+in+guinea+pigs.">Prolonged maternal vitamin C deficiency overrides preferential fetal ascorbate transport but does not influence perinatal survival in guinea pigs.</a> Br J Nutr. 110 (9), 1573-1579 (2013).</li><li>Greulich, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Secretory+products+of+guinea+pig+epicardial+fat+induce+insulin+resistance+and+impair+primary+adult+rat+cardiomyocyte+function.">Secretory products of guinea pig epicardial fat induce insulin resistance and impair primary adult rat cardiomyocyte function.</a> J Cell Mol Med. 15 (11), 2399-2410 (2011).</li><li>Swifka, J., Weiss, J., Addicks, K., Eckel, J., Rosen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epicardial+fat+from+guinea+pig+a+model+to+study+the+paracrine+network+of+interactions+between+epicardial+fat+and+myocardium.">Epicardial fat from guinea pig a model to study the paracrine network of interactions between epicardial fat and myocardium.</a> Cardiovasc Drugs Ther. 22 (2), 107-114 (2008).</li><li>Pilny, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+hematology+of+rodent+species.">Clinical hematology of rodent species.</a> Vet.Clin North Am Exot Anim Pract. 11 (3), 523-vii (2008).</li><li>Franco, N. H., Olsson, I. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scientists+and+the+3Rs:+attitudes+to+animal+use+in+biomedical+research+and+the+effect+of+mandatory+training+in+laboratory+animal+science.">Scientists and the 3Rs: attitudes to animal use in biomedical research and the effect of mandatory training in laboratory animal science.</a> Lab Anim. 48 (1), 50-60 (2014).</li><li>Van, L. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=eAssessing+the+application+of+the+3Rs+a+survey+among+animal+welfare+officers+in+The+Netherlands.">eAssessing the application of the 3Rs a survey among animal welfare officers in The Netherlands.</a> Lab Anim. 47 (3), 210-219 (2013).</li><li>Sloan, R. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+doses+of+ketamine-xylazine+anesthesia+reduce+cardiac+ischemia-reperfusion+injury+in+guinea+pigs.">High doses of ketamine-xylazine anesthesia reduce cardiac ischemia-reperfusion injury in guinea pigs.</a> J Am Assoc Lab Anim Sci. 50 (3), 349-354 (2011).</li><li>Jacobson, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+anaesthetic+regimen+for+surgical+procedures+in+guinea+pigs.">A novel anaesthetic regimen for surgical procedures in guinea pigs.</a> Lab Anim. 35 (3), 271-276 (2001).</li><li>Saha, J. K., Xia, J., Grondin, J. M., Engle, S. K., Jakubowski, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+hyperglycemia+induced+by+ketamine+xylazine+anesthesia+in+rats+mechanisms+and+implications+for+preclinical+models.">Acute hyperglycemia induced by ketamine xylazine anesthesia in rats mechanisms and implications for preclinical models.</a> Exp Biol Med(Maywood). 230 (10), 777-784 (2005).</li></ol>

Los autores no tienen nada que revelar. Todos los procedimientos fueron aprobados por la Ley de Experimentación Animal de Dinamarca, que está de acuerdo con el Consejo de Europa del Convenio ETS 123.

En comparación con los ratones y las ratas, conejillos de Indias son temerosos por naturaleza y deben ser abordados con calma y manejados correctamente para reducir el estrés. Desde el punto de vista del bienestar animal, actuando con cuidado es naturalmente una prioridad; Sin embargo, esto también reducirá el riesgo de efectos de ansiedad asociada a los datos recogidos por ej., aumento de los niveles sanguíneos de corticosteroides y glucosa 12. Del mismo modo, la manipulación diaria habituar a...

La cobaya es un modelo animal experimental valiosa y validado debido a un número de similitudes biológicas a los seres humanos, tales como un requisito para un suministro dietético de la vitamina C, la lipoproteína de plasma comparables enzimas metabolizadoras y perfiles de lipoproteínas, así como similitudes compartidas con placentación humana y 1-3,7,8 desarrollo prenatal. Esto hace que el conejillo de indias un modelo atractivo y conveniente para efectos de las enfermedades asociadas a la dieta tales como la enfermedad no alcohólica del hígado graso, las enfermedades cardiovasculares y los efectos putativos de la deficiencia de vitamina C, sino también el efecto de, por ejemplo estudiando., Intervención dietética materna en el desarrollo descendencia. Muestreo de sangre repetida a menudo se requiere tanto a largo como a corto plazo en los estudios in vivo. Debido a las diferencias anatómicas específicas de las especies es necesaria la modulación de la técnica de muestreo para obtener muestras de sangre en los conejillos de indias en comparación con otros modelos de roedores <sup&gt; 4,5. Esto incluye la variación en el curso de las venas y arterias, y también que los conejillos de indias no tienen una cola, por lo tanto tiene diferentes requisitos y opciones tanto para el muestreo y la manipulación. El muestreo de la safena o vena tarsal, induce mínimas molestias y el estrés en el animal y no requiere anestesia 3,9. Esta técnica permite que las muestras de pequeñas cantidades de sangre (100-400 l), por ejemplo repitió., Para determinar los marcadores bioquímicos en el plasma. Si un tamaño de muestra incluso más pequeño es suficiente (50-100 l), esto con bastante facilidad puede obtenerse por punción de la vena de la oreja. Esta técnica también se puede llevar a cabo en animales conscientes y es útil por ejemplo cuando se mide la glucosa en sangre 10,11. El muestreo de la vena yugular permite colección de grandes cantidades de sangre (1-2 ml), pero requiere anestesia. A continuación, presentamos cuatro técnicas de muestreo de sangre diferentes, ya sea para cobayas conscientes o anestesiados. El procedures son todos los procedimientos no terminales siempre que los volúmenes de muestra y número de muestras no exceden las directrices para la recogida de sangre en animales de laboratorio 6. Es en interés de la buena ciencia, así como de bienestar de los animales que el estrés se debe mantener a un mínimo. En consecuencia, sólo bien entrenado y personal competente debe realizar los procedimientos con animales.

<table border="0" cellpadding="0" cellspacing="0" width="944">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:295px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:315px;">Comments/Description</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Electric shaver</td>
			<td style="width:295px;">Wella (Contura), Denmark</td>
			<td style="width:119px;">273207</td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Syringes&#160;</td>
			<td style="width:295px;">B.Braun-Omnifix-F, Germany</td>
			<td style="width:119px;">9161406V</td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Needles</td>
			<td style="width:295px;">BD Microlance,Spain</td>
			<td style="width:119px;">301156</td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Microvette collection tube&#160;</td>
			<td style="width:295px;">Sarstedt, D-51588N&#252;mbrecht, Germany</td>
			<td style="width:119px;">201,288,100</td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Accu-Check analyzer</td>
			<td style="width:295px;">Roche A/S Diagnostics, Denmark</td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Heparin 5000 IE/ml</td>
			<td style="width:295px;">LEO Pharma, Denmark</td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Anesthesia</td>
			<td style="width:295px;">Zoletil 50, Chemvet, Denmark</td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Anesthesia</td>
			<td style="width:295px;">Narcoxyl vet 20 mg/ml, Intervet, Denmark</td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Anesthesia</td>
			<td style="width:295px;">Torbugesic vet 10 mg/ml, Scanvet, Denmark</td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Neutral eye ointment</td>
			<td style="width:295px;"></td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Gauze or a cotton swab&#160;</td>
			<td style="width:295px;"></td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Disinfectant (70% alcohol)</td>
			<td style="width:295px;"></td>
			<td style="width:119px;"></td>
			<td>Alternative product may be used. Multiple suppliers</td>
		</tr>
	</tbody>
</table>

non-terminal blood sampling techniques in guinea pigs

Los conejillos de indias poseen varias similitudes biológicas a los seres humanos y se validan los modelos animales experimentales 1-3. Sin embargo, el uso de conejillos de indias actualmente representa un área relativamente estrecha de datos de investigación y descriptivos sobre la metodología específica es correspondientemente escasa. Las características anatómicas de los conejillos de Indias son un poco diferente de otros modelos de roedores, por lo tanto, la modulación de las técnicas de muestreo para dar cabida a las diferencias específicas de cada especie, por ejemplo., En comparación con los ratones y las ratas, son necesarias para obtener muestras suficientes y de alta calidad. Como tanto a largo como a corto plazo en los estudios in vivo a menudo requieren repetir el muestreo de sangre la elección de la técnica debe ser bien considerado con el fin de reducir el estrés y el malestar en los animales, sino también para asegurar la supervivencia, así como el cumplimiento de los requisitos de tamaño de la muestra y la accesibilidad. Muestras de sangre venosa se ​​pueden obtener en un número de sitios en los conejillos de indias por ejemplo., La safena y yugularvenas, cada técnica que contiene tanto ventajas como desventajas 4,5. A continuación, presentamos cuatro técnicas de muestreo de sangre diferentes, ya sea para cobayas conscientes o anestesiados. Los procedimientos son los procedimientos no terminales siempre que los volúmenes de muestra y número de muestras no exceden las directrices para la recogida de sangre en animales de laboratorio 6. Todos los métodos descritos han sido probados y solicitado repetido en el muestreo de sangre in vivo en los estudios dentro de nuestro centro de investigación a fondo.

Se han presentado cuatro enfoques diferentes de técnicas in vivo no terminales en muestras de sangre, ya sea en cobayas conscientes o anestesiados. Figura 1 ilustra el curso de la safena y la vena lateral del tarso en el conejillo de indias y los posibles sitios de punción. Venas del oído visibles en la superficie dorsal de una oreja de cerdo de guinea se ilustran en la Figura 2 Estas venas pueden ser utilizados para tomar muestras de sangre cuando se requiere sólo...

Watch this Scientific Journal Video about Non-Terminal Blood Sampling Techniques in Guinea Pigs at JoVE.com

Non-Terminal Blood Sampling Techniques in Guinea Pigs

Aunque un modelo conocido, el conejillo de indias en la actualidad representa un nicho en las ciencias experimentales en animales y datos limitados está disponible en la ejecución de la mayoría de los procedimientos. Aquí presentamos cuatro enfoques diferentes para no terminal en las técnicas de muestreo de sangre in vivo, ya sea en cobayas conscientes o anestesiados.

Técnicas de muestreo de sangre no terminal en los conejillos de Indias

Guinea pigs possess several biological similarities to humans and are validated experimental animal models1-3. However, the use of guinea pigs currently ...

non-terminal-blood-sampling-techniques-in-guinea-pigs

Research

JoVE Journal

Biology

37.1K vistas.  University of Copenhagen.  Aunque un modelo conocido, el conejillo de indias en la actualidad representa un nicho en las ciencias experimentales en animales y datos limitados está disponible en la ejecución de la mayoría de los procedimientos. Aquí presentamos cuatro enfoques diferentes para no terminal en las técnicas de muestreo de sangre in vivo, ya sea en cobayas conscientes o anestesiados. 

Video: Non-Terminal Blood Sampling Techniques in Guinea Pigs

Optical Recording of Electrical Activity in Guinea-pig Enteric Networks using Voltage-sensitive Dyes

The enteric nervous system (ENS) is a self-contained network with identified functions, capable of performing complex behaviors in isolation. Its neurons (10 to 25 &mu;m in diameter) are arranged in plexuses that are confined to distinct planes of the gut wall 1; the myenteric plexus can be found between the longitudinal and circular muscle layers, and the submucous plexus between the circular muscle layer and the mucosa. Since the effector systems for these plexuses (transporting epithelium, endocrine cells, immune elements, blood vessels and smooth muscle) are also contained within the gut wall, semi-intact preparations can be dissected that preserve individual components of different reflex pathways. The behavior of the effector systems is controlled by the submucous and myenteric plexuses acting in concert. Therefore, detailed knowledge of synaptic interactions within and between ganglia, and of communication between the plexuses, is essential for understanding normal gastrointestinal function. The ENS, as an intact nervous system, is a unique experimental model in which one can correlate molecular and cellular events with the electrical behavior of the neuronal network and its physiological outputs. Because of the quasi-two-dimensional organization of its plexuses, the ENS is particularly well suited for the study of neural networks using multiple site optical recording techniques that employ voltage-sensitive dyes 2,7,8,9. We will illustrate here the use of a relatively new naphthylstyryl-pyridinium dye (di-4-ANEPPDHQ) 3 that offers multiple advantages over its predecessors, including very low phototoxicity, slow rate of internalization, and remarkable chemical stability. When used in conjunction with a camera that permits sub-millisecond time resolution, this dye allows us to monitor the electrical activity of all the neurons in the field of view with a maximal spatial resolution of ~ 2.5 &mu;m at 100X magnification. At lower magnification (10X or 20X), the sacrifice of single-cell resolution is compensated by a gain in perspective, revealing the intricacies of the inter-ganglionic circuitry.

This protocol illustrates how voltage-sensitive dyes enable optical recording of electrical activity from intact neural networks such as the plexuses of the guinea-pig enteric nervous system, with an adjustable resolution that ranges from single-cells to multi-ganglionic circuitry.

Grabación óptica de la actividad eléctrica en el conejillo de Indias Redes entérica con tintes sensibles al voltaje

The enteric nervous system (ENS) is a self-contained network with identified functions, capable of performing complex behaviors in isolation. Its neurons ...

Investigación

Biología

Patch Clamp and Perfusion Techniques for Studying Ion Channels Expressed in Xenopus oocytes

The protocol presented here is designed to study the activation of the large conductance, voltage- and Ca2+-activated K+ (BK) channels. The protocol may also be used to study the structure-function relationship for other ion channels and neurotransmitter receptors1. BK channels are widely expressed in different tissues and have been implicated in many physiological functions, including regulation of smooth muscle contraction, frequency tuning of inner hair cells and regulation of neurotransmitter release2-6. BK channels are activated by membrane depolarization and by intracellular Ca2+ and Mg2+ 6-9. Therefore, the protocol is designed to control both the membrane voltage and the intracellular solution. In this protocol, messenger RNA of BK channels is injected into Xenopus laevis oocytes (stage V-VI) followed by 2-5 days of incubation at 18&deg;C10-13. Membrane patches that contain single or multiple BK channels are excised with the inside-out configuration using patch clamp techniques10-13. The intracellular side of the patch is perfused with desired solutions during recording so that the channel activation under different conditions can be examined. To summarize, the mRNA of BK channels is injected into Xenopus laevis oocytes to express channel proteins on the oocyte membrane; patch clamp techniques are used to record currents flowing through the channels under controlled voltage and intracellular solutions.

Patch Clamp and Perfusion Techniques for Studying Ion Channels Expressed in Xenopus oocytes

Ionic current of BK channels is recorded using patch clamp techniques. BK channels are expressed in Xenopus oocytes by injecting messenger RNA. The intracellular solution during patch clamp recordings is controlled by a perfusion system.

Patch clamp y técnicas de perfusión para el estudio de los canales iónicos expresados ​​en Xenopus Ovocitos

The protocol presented here is designed to study the activation of the large conductance, voltage- and Ca2+-activated K+ (BK) channels. The protocol may ...

Isolation and Culture of Pulmonary Endothelial Cells from Neonatal Mice

Endothelial cells provide a useful research model in many areas of vascular biology. Since its first isolation 1, human umbilical vein endothelial cells (HUVECs) have shown to be convenient, easy to obtain and culture, and thus are the most widely studied endothelial cells. However, for research focused on processes like angiogenesis, permeability or many others, microvascular endothelial cells (ECs) are a much more physiologically relevant model to study 2. Furthermore, ECs isolated from knockout mice provide a useful tool for analysis of protein function ex vivo. Several approaches to isolate and culture microvascular ECs of different origin have been reported to date 3-7, but consistent isolation and culture of pure ECs is still a major technical problem in many laboratories. Here, we provide a step-by-step protocol on a reliable and relatively simple method of isolating and culturing mouse lung endothelial cells (MLECs). In this approach, lung tissue obtained from 6- to 8-day old pups is first cut into pieces, digested with collagenase/dispase (C/D) solution and dispersed mechanically into single-cell suspension. MLECS are purified from cell suspension using positive selection with anti-PECAM-1 antibody conjugated to Dynabeads using a Magnetic Particle Concentrator (MPC). Such purified cells are cultured on gelatin-coated tissue culture (TC) dishes until they become confluent. At that point, cells are further purified using Dynabeads coupled to anti-ICAM-2 antibody. MLECs obtained with this protocol exhibit a cobblestone phenotype, as visualized by phase-contrast light microscopy, and their endothelial phenotype has been confirmed using FACS analysis with anti-VE-cadherin 8 and anti-VEGFR2 9 antibodies and immunofluorescent staining of VE-cadherin. In our hands, this two-step isolation procedure consistently and reliably yields a pure population of MLECs, which can be further cultured. This method will enable researchers to take advantage of the growing number of knockout and transgenic mice to directly correlate in vivo studies with results of in vitro experiments performed on isolated MLECs and thus help to reveal molecular mechanisms of vascular phenotypes observed in vivo.

Here, we describe a protocol for isolation and culture of murine pulmonary endothelial cells. This method comprises mechanic and enzymatic lung tissue dissociation as well as a 2-step purification process using anti-PECAM-1 and anti-ICAM-2 antibodies conjugated to magnetic beads, which produces a pure endothelial cell population of mostly microvascular origin.

Aislamiento y cultivo de células endoteliales pulmonares de ratones recién nacidos

Endothelial cells provide a useful research model in many areas of vascular biology. Since its first isolation 1, human umbilical vein endothelial cells ...

Techniques for the Analysis of Extracellular Vesicles Using Flow Cytometry

Extracellular Vesicles (EVs) are small, membrane-derived vesicles found in bodily fluids that are highly involved in cell-cell communication and help regulate a diverse range of biological processes. Analysis of EVs using flow cytometry (FCM) has been notoriously difficult due to their small size and lack of discrete populations positive for markers of interest. Methods for EV analysis, while considerably improved over the last decade, are still a work in progress. Unfortunately, there is no one-size-fits-all protocol, and several aspects must be considered when determining the most appropriate method to use. Presented here are several different techniques for processing EVs and two protocols for analyzing EVs using either individual detection or a bead-based approach. The methods described here will assist with eliminating the antibody aggregates commonly found in commercial preparations, increasing signal&#8211;to-noise ratio, and setting gates in a rational fashion that minimizes detection of background fluorescence. The first protocol uses an individual detection method that is especially well suited for analyzing a high volume of clinical samples, while the second protocol uses a bead-based approach to capture and detect smaller EVs and exosomes.

Many different methods exist for the measurement of extracellular vesicles (EVs) using flow cytometry (FCM). Several aspects should be considered when determining the most appropriate method to use. Two protocols for measuring EVs are presented, using either individual detection or a bead-based approach.

Técnicas para el Análisis de extracelular vesículas Usando citometría de flujo

Extracellular Vesicles (EVs) are small, membrane-derived vesicles found in bodily fluids that are highly involved in cell-cell communication and help ...

Dried Blood Spots - Preparing and Processing for Use in Immunoassays and in Molecular Techniques

The idea of collecting blood on a paper card and subsequently using the dried blood spots (DBS) for diagnostic purposes originated a century ago. Since then, DBS testing for decades has remained predominantly focused on the diagnosis of infectious diseases especially in resource-limited settings or the systematic screening of newborns for inherited metabolic disorders and only recently have a variety of new and innovative DBS applications begun to emerge. For many years, pre-analytical variables were only inappropriately considered in the field of DBS testing and even today, with the exception of newborn screening, the entire pre-analytical phase, which comprises the preparation and processing of DBS for their final analysis has not been standardized. Given this background, a comprehensive step-by-step protocol, which covers al the essential phases, is proposed, i.e., collection of blood; preparation of blood spots; drying of blood spots; storage and transportation of DBS; elution of DBS, and finally analyses of DBS eluates. The effectiveness of this protocol was first evaluated with 1,762 coupled serum/DBS pairs for detecting markers of hepatitis B virus, hepatitis C virus, and human immunodeficiency virus infections on an automated analytical platform. In a second step, the protocol was utilized during a pilot study, which was conducted on active drug users in the German cities of Berlin and Essen.

The preparing and processing of dried blood spots (DBS) for their final analysis are still poorly standardized for most diagnostic applications. To overcome this shortcoming, a comprehensive step-by-step protocol is suggested and subsequently evaluated with regard to its effectiveness for detecting markers of viral infections.

Manchas de sangre seca - preparación y procesamiento para su uso en inmunoensayos y en técnicas moleculares

The idea of collecting blood on a paper card and subsequently using the dried blood spots (DBS) for diagnostic purposes originated a century ago. Since ...

Sampling Blood from the Lateral Tail Vein of the Rat

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, proteins, and glucose, yet the composition of the blood is dynamically regulated and easily perturbed. One factor that can change the blood composition is the stress response triggered by the sampling procedure, which can contribute to variability in the measures of interest. Here we describe a procedure for blood sampling from the lateral tail vein in the rat. This procedure offers significant advantages over other more commonly used techniques. It permits rapid sampling with minimal pain or invasiveness, without anesthesia or analgesia. Additionally, it can be used to obtain large volume samples (upwards of 1 ml in some rats), and it may be used repeatedly across experimental days. By minimizing the stress response and pain resulting from blood sampling, measures can more accurately reflect the true basal state of the animal, with minimal influence from the sampling procedure itself.

Blood samples are useful for assessing biomarkers of physiological states or disease in vivo. Here we describe the methodology to sample blood from the lateral tail vein in the rat. This method provides rapid samples with minimal pain and invasiveness.

Toma de muestras de sangre de la vena lateral de la cola de la rata

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, ...

Micron-scale Phenotyping Techniques of Maize Vascular Bundles Based on X-ray Microcomputed Tomography

It is necessary to accurately quantify the anatomical structures of maize materials based on high-throughput image analysis techniques. Here, we provide a 'sample preparation protocol' for maize materials (i.e., stem, leaf, and root) suitable for ordinary microcomputed tomography (micro-CT) scanning. Based on high-resolution CT images of maize stem, leaf, and root, we describe two protocols for the phenotypic analysis of vascular bundles: (1) based on the CT image of maize stem and leaf, we developed a specific image analysis pipeline to automatically extract 31 and 33 phenotypic traits of vascular bundles; (2) based on the CT image series of maize root, we set up an image processing scheme for the three-dimensional (3-D) segmentation of metaxylem vessels, and extracted two-dimensional (2-D) and 3-D phenotypic traits, such as volume, surface area of metaxylem vessels, etc. Compared with traditional manual measurement of vascular bundles of maize materials, the proposed protocols significantly improve the efficiency and accuracy of micron-scale phenotypic quantification.

We provide a novel method to improve the X-ray absorption contrast of maize tissue suitable for ordinary microcomputed tomography scanning. Based on CT images, we introduce a set of image-processing workflows for different maize materials to effectively extract microscopic phenotypes of vascular bundles of maize.

Técnicas de microescala Phenotyping de maíz haces vasculares basados en tomografía de rayos x Microcomputed

It is necessary to accurately quantify the anatomical structures of maize materials based on high-throughput image analysis techniques. Here, we provide a ...

Gonadectomy and Blood Sampling Procedures in the Small Size Teleost Model Japanese Medaka (Oryzias latipes)

Sex steroids, produced by the gonads, play an essential role in brain and pituitary tissue plasticity and in the neuroendocrine control of reproduction in all vertebrates by providing feedback to the brain and pituitary. Teleost fishes possess a higher degree of tissue plasticity and variation in reproductive&#160;strategies compared to mammals and appear to be useful models to investigate the role of sex steroids and the mechanisms by which they act. The removal of the main source of sex steroid production using gonadectomy together with blood sampling to measure steroid levels has been well-established and fairly feasible in bigger fish and is a powerful technique to investigate the role and effects of sex steroids. However, these techniques raise challenges when implemented in small size teleost models. Here, we describe the step-by-step procedures of gonadectomy in both males and female Japanese medaka followed by blood sampling. These protocols are shown to be highly feasible in medaka indicated by a high survival rate, safety for the life span and phenotype of the fish, and reproducibility in terms of sex steroid clearance. The use of these procedures combined with the other advantages of using this small teleost model will greatly improve the understanding of feedback mechanisms in the neuroendocrine control of reproduction and tissue plasticity provided by sex steroids in vertebrates.

Gonadectomy and Blood Sampling Procedures in the Small Size Teleost Model Japanese Medaka Oryzias latipes

The article describes a quick protocol to gonadectomize and sample blood from the small teleost fish, using Japanese medaka (Oryzias latipes) as a model, to investigate the role of sex steroids in animal physiology.

Procedimientos de gonadectomía y muestreo de sangre en el modelo de teleósto de tamaño pequeño japonés Medaka (Oryzias latipes)

Sex steroids, produced by the gonads, play an essential role in brain and pituitary tissue plasticity and in the neuroendocrine control of reproduction in ...

Isolation of Retinal Pigment Epithelial Cells from Guinea Pig Eyes

This protocol describes the isolation of cells of the retinal pigment epithelium (RPE) from the eyes of young pigmented guinea pigs for potential application in molecular biology studies, including gene expression analyses. In the context of eye growth regulation and myopia, the RPE likely plays a role as a cellular relay for growth modulatory signals, as it is located between the retina and the two walls of the eye, such as the choroid and sclera. While protocols for isolating the RPE have been developed for both chicks and mice, these protocols have proven not to be directly translatable to the guinea pig, which has become an important and widely used mammalian myopia model. In this study, molecular biology tools were used to examine the expression of specific genes to confirm that the samples were free of contamination from the adjacent tissues. The value of this protocol has already been demonstrated in an RNA-Seq study of RPE from young pigmented guinea pigs exposed to myopia-inducing optical defocus. Beyond eye growth regulation, this protocol has other potential applications in studies of retinal diseases, including myopic maculopathy, one of the leading causes of blindness in myopes, in which the RPE has been implicated. The main advantage of this technique is that it is relatively simple and&#160;once perfected, yields high-quality RPE samples suitable for molecular biology studies, including RNA analysis.

We describe a simple and efficient method for isolating cells of the retinal pigment epithelium (RPE) cells from the eyes of young pigmented guinea pigs. This procedure allows for follow-up molecular biology studies on the isolated RPE, including gene expression analyses.

Aislamiento de células epiteliales pigmentarias de la retina de ojos de conejillo de indias

This protocol describes the isolation of cells of the retinal pigment epithelium (RPE) from the eyes of young pigmented guinea pigs for potential ...

Neutrophil Lifespan Extension with CLON-G and an In Vitro Spontaneous Death Assay

The average lifespan of a neutrophil is less than 24 h, which limits basic research on neutrophils and the application of neutrophil studies. Our previous research indicated that multiple pathways could mediate the spontaneous death of neutrophils. A cocktail was developed by simultaneously targeting these pathways, caspases-lysosomal membrane permeabilization-oxidant-necroptosis inhibition plus granulocyte colony-stimulating factor (CLON-G), which prolonged the neutrophil lifespan to greater than 5 days without significantly compromising the neutrophil function. Concurrently, a reliable and stable protocol for assessing and evaluating neutrophil death was also developed. In this work, we show that CLON-G can prolong the neutrophil lifespan in vitro to more than 5 days, and we exhibit the lengthening of the neutrophil lifespan with FACS and confocal fluorescence microscopy. This report introduces procedures for the preparation of CLON-G and showcases an in vitro spontaneous death assay of neutrophils, which can be used for the study of neutrophils and for subsequently interrogating neutrophil death, thus providing a reliable resource for the neutrophil community.

Neutrophil Lifespan Extension with CLON-G and an In Vitro Spontaneous Death Assay

This protocol details the preparation of CLON-G to extend the neutrophil lifespan to greater than 5 days and provides a reliable procedure for evaluating neutrophil death with flow cytometry and confocal fluorescence microscopy.

Extensión de la vida útil de los neutrófilos con CLON-G y un ensayo de muerte espontánea in vitro

The average lifespan of a neutrophil is less than 24 h, which limits basic research on neutrophils and the application of neutrophil studies. Our previous ...