Los autores agradecen a los Dres. Kentaro Nagaoka (Universidad de Tokio de Agricultura y Tecnología) y Wataru Iio (prefectura de Ibaraki) para la discusión útil. Esta investigación fue financiada en parte por Ibaraki Cooperación Universitaria entre Agricultura y Ciencias Médicas (IUCAM) (El MEXT, Japón) y el Proyecto de Investigación sobre el Desarrollo de Productos y alimentos con beneficios para la salud, la promoción de la agricultura (NARO) (El MAFF, Japón) .

Los estudios con animales fueron aprobados por y cumplen las directrices tanto del Cuidado de Animales y el empleo Comisión de la Universidad de Ibaraki y el Ministerio de Educación, Cultura, Deportes, Ciencia y Tecnología (MEXT), Japón (No.71 Notificación). Una visión general completa del protocolo se muestra en la Figura 1. 1. Aparato <ol><li> Prepare dos tipos de jaulas: una sola jaula (ancho [W] x profundidad [D] × altura [H] = 143 mm × 293 mm × 148 mm), y una &quot;derrota sociales (SD)&quot; jaula (W × D × H = 220 mm × 320 mm × 135 mm). </li><li> Como se muestra en la Figura 2, dividir la jaula SD en dos compartimentos con un divisor de acrílico transparente de planchar (5 mm de espesor) con 15 agujeros circulares (3 × 5 matriz: 8 mm de diámetro). </li><li> Obtener las virutas de madera y afeitado a base de árboles de abeto, bolitas de comida purificada-dieta, y una botella de agua para beber. Además, obtener toallas de papel, una máscara y guantes de látex. </li&gt; <li> Para la prueba de la interacción social, preparar un escenario de campo abierto (W x D x H = 40 cm × 40 cm × 40 cm) hecho de cloruro de polivinilo de color gris, un peso de acero (190 g), y un cuadro de la interacción de plástico (W × D × H = 10 cm × 10 cm × 13 cm; 100 g) con tres ventanas de malla de alambre (W x D = 5 cm x 5 cm) (Figura 3). </li><li> Coloque una cámara CCD (2,8 a 12 mm; F ​​= 1: 1.4; 3.1 pulgadas CCD) y un sistema de seguimiento automatizado en la sala de pruebas de comportamiento en el animalario. Coloque una plataforma adecuada para las jaulas de ratón en la sala de pruebas de comportamiento para habituar a los ratones para el medio ambiente de la sala de pruebas por lo menos durante 30 minutos. </li></ol> 2. La habituación con el Medio Ambiente <ol><li> Utilice masculino C57BL / 6JJmsSlc (B6) ratones que son 7 semanas de edad y SLC masculina: ICR (ICR) ratones que son más de 5 meses de edad y entregar a la instalación de una compañía de la cría de animales. </li><li> Independientemente mover dos grupos de ratones B6 (n= 12 en cada grupo) para la instalación; utilizar un grupo (screener B6 ratones) para la selección de los ratones agresivos ICR y otro grupo (los ratones sujetos B6) para el desarrollo del modelo sCSDS. </li><li> Introducir ratones ICR (n = 12) a las instalaciones con el fin de defender sus comportamientos agresivos. </li><li> Casa los ratones individualmente en jaulas individuales durante 1 semana bajo un ciclo de luz-oscuridad de 12 horas (alrededor de 100 lux de luz fluorescente, luces encendidas a las 08:00) con la temperatura constante (alrededor de 23 ° C) y los niveles de humedad (alrededor de 40%) con el fin de habituar al entorno. Partición cada jaula mediante la colocación de placas de plástico de color blanco entre las jaulas para que los ratones que no están afectados por el comportamiento de los ratones vecinos. </li><li> Hacer bolitas de comida purificada-dieta y agua de ósmosis inversa disponible ad libitum. Utilice AIN-93G Chow porque los ingredientes de otras pastillas de dieta no purificados pueden variar. </li><li> Medir el peso corporal, la ingesta de alimentos (FI), y la ingesta de agua (WI) de los ratones cada día. Calcular la baumento de peso ody (BWG) desde el día inicial. </li></ol> 3. Proyección de agresivo ratones ICR <ol><li> Después de la habituación por 1 semana como se mencionó anteriormente, la pantalla los ratones ICR (residente) mediante pruebas de residente-intrusión para una prueba de 3 minutos con ratones B6 screener (intruso; 8 semanas de edad) en la tarde (14: 00-17: 00) bajo la iluminación de alrededor de 300 lux en la sala de la vivienda. <ol><li> Específicamente, probar cada ratón ICR para los tres ensayos por día durante 5 días consecutivos (15 ensayos en total) hacia diversos ratones B6 como sea posible para encontrar ratones ICR muestran alta agresión hacia los intrusos. Durante las pruebas, grabar la latencia ataque y duración de la conducta agresiva (movimientos rápidos con ataque mordaz). </li></ol></li><li> Identificar ratones ICR hiperagresivos marcando las heridas daños en ratones B6 intruso después de cada ensayo. </li><li> Calcular la relación de ensayos en los que la latencia de ataque es de menos de 30 seg como un primer índice de la puntuación de la agresión. </li><li> doalculate la relación de ensayos en los que la latencia de ataque es menos de 3 min como un segundo índice de la puntuación de la agresión. </li><li> Evaluar los resultados de agresión desde el primer índice. Utilice el segundo índice cuando el primer índice es igual. </li><li> Seleccione los ratones ICR que tenían puntuaciones altas agresión sin comportamientos hiper-agresiva como ratones agresivos ICR. Utilice los ratones agresivos ICR en repetidas ocasiones a lo largo de la siguiente serie de experimentos hasta aproximadamente 12 meses de edad; sin embargo, realizar el proceso de selección para los ratones ICR agresivos como se describe anteriormente antes de cada experimento para confirmar la agresividad de ratones ICR. </li><li> Después de cada sesión de la proyección, registrar el grado de lesión de los ratones B6 screener. Si un ratón está herido, aislar el ratón en una sola jaula y observar el progreso mediante la comprobación de su ganancia de peso corporal, la ingesta de alimentos y la ingesta de agua. En el caso de las heridas graves que afectan a la fisiología y el comportamiento en ratones, la eutanasia de acuerdo con I localesDirectrices ACUC. </li></ol> 4. sCSDS <ol><li> Introducir sujeto ratones B6 7 días antes (día -6) el día de la exposición inicial estrés (día 1) y la casa de los ratones individualmente en jaulas individuales para habituarse al entorno. </li><li> Tres días antes del día 1 (el día -2), mover los ratones ICR agresivos en un compartimiento de cada jaula SD, que se divide por un divisor de acrílico para dejar que los ratones establecen sus territorios en las jaulas SD (el mismo número de sujetos B6 ratones). </li><li> Dividir las jaulas SD mediante el uso de tablas de partición de color blanco, como en la condición de una sola jaula descrito anteriormente. </li><li> Para los ratones B6 no estresado de control, preparar jaulas SD (media del número de ratones) para mantener los ratones en pares; colocar dos ratones en cada compartimiento dividido por el divisor en una jaula de SD durante 10 días. </li><li> Después de las mediciones diarias BWG, FI y WI en el día 1, los ratones lugar sujeto B6 en uno de los compartimentos de las jaulas SD (casa-jaula de residente) en el faetrnoon (14: 00-16: 00) con la iluminación de alrededor de 300 lux en la sala de la vivienda y medir el tiempo de contacto físico desde el primer bocado de ataque para completar la prueba residente intruso. </li><li> El día 1, establecer el tiempo de contacto físico a 5 min de la primera mordida ataque y han observadores contar el número de picaduras de ataque por ratones ICR que se dirigen preferentemente en la parte posterior o flancos del oponente como lo describe Miczek et al. 20 a determinar el grado de estrés físico a ratones B6. </li><li> Después del tiempo de contacto físico, rescate sujetos ratones B6, y comprobar y registrar su estado y de las heridas de la piel. Luego, coloque los ratones B6 en otro compartimento junto a los ratones ICR en las jaulas SD hasta que la exposición al estrés físico al día siguiente. </li><li> Debido a que el divisor de acrílico en la jaula SD es transparente y contiene agujeros, exponer sujetos ratones B6 a diversas tensiones emocionales, incluyendo visuales, auditivas y estímulos olfativos, desde los ratones ICR en el compartimiento vecinoción de la jaula SD durante 24 horas todos los días. </li><li> Mida la BWG, FI y WI de ratones B6 de control de todos los días y luego colocarlos en cada compartimiento en las jaulas SD durante 1 día. </li><li> El día 2, después de las mediciones diarias de BWG, FI y WI, introducir sujetos ratones B6 en los territorios de otros ratones ICR para exponerlos al estrés físico. </li><li> Establezca la duración del contacto físico en 4.5 minutos de la primera mordida ataque en el día 2, y contar el número de picaduras de ataque. </li><li> Mueva ratones B6 de control en diferentes compartimentos y cambiar las combinaciones de pares con el fin de mezclar la colocación y socio de los pares de todos los días. </li><li> Disminuir la duración de contacto físico por 0.5 min por día, de modo que la duración en día 10 se establece en 0,5 min desde el primer bocado ataque. </li><li> El día 7, reemplazar aproximadamente la mitad de las virutas de madera en todos los compartimentos en las jaulas SD. </li><li> Después de la exposición a la última tensión física en el día 10, mueva sujetos ratones B6 en jaulas individuales. Al igual que en los sujetos ratones B6, mueva ratones B6 de control en jaulas individuales en el día 10. </li><li> Si un ratón ICR no muestra picaduras de ataque hasta 5 minutos en cada ensayo el día 1 al 10, dar por terminado el juicio. Vuelva a colocar el ratón ICR con ratones ICR agresivos piezas y llevar a cabo un ensayo alternativo para el ratón sujetos B6. </li><li> Si un ratón está herido, aislar el ratón en una sola jaula y observar el progreso mediante la comprobación de su ganancia de peso corporal, la ingesta de alimentos y la ingesta de agua. Siga las directrices de su IACUC para la analgesia. En el caso de las heridas graves que afectan a la fisiología y el comportamiento en ratones, la eutanasia de acuerdo a las directrices locales IACUC. </li></ol> 5. Prueba de Prevención Social (Interacción Social Test) <ol><li> Realizar pruebas de comportamiento de evitación social por la mañana (09: 00-12: 00) en el día 11. </li><li> Treinta minutos antes de la prueba, la transferencia de las jaulas de los ratones de control y sujeto B6 en un estante (tenue luz de menos de 1 lux) en el comportamientosala de pruebas en condiciones de iluminación de menos de 20 lux para que puedan habitúan al medio ambiente. </li><li> Para reducir los efectos de la orden, la prueba alterna ratones control y sujeto B6. </li><li> Limpie una arena de campo abierto (que se ilumina con una luz de 20 lux en el centro del campo) y una caja de interacción plástico usando toallas de papel empapadas con etanol al 70% antes de la prueba de comportamiento para cada ratón para eliminar las heces, la orina y los olores . </li><li> Coloque un ratón ICR desconocida (no se utiliza como un agresor) desde una sola jaula cerca del aparato de campo abierto. </li><li> Coloque un ratón B6 en el campo abierto de la caja interacción vacante como se muestra en la Figura 4. Monitorear y analizar su comportamiento durante 2,5 min usando el sistema de análisis automático (descrito en la etapa 5.10). </li><li> Después de la primera prueba, retire el ratón B6 desde el campo y colocarlo en su jaula. </li><li> A raíz de esto, coloque el ratón ICR desconocida masculina (objetivo social) en el cuadro de la interacción y luego introducir la B6en ratón del campo abierto y monitorear su comportamiento durante 2,5 minutos. </li><li> Después de la segunda prueba, devuelva tanto el B6 y ratones ICR a sus jaulas, y limpiar el campo y el cuadro de la interacción como se mencionó anteriormente. </li><li> Repita estos pasos para cada ratón B6 para probar su comportamiento social. Durante cada ensayo, ficha películas de primera visión usando una cámara CCD. <ol><li> Después de las pruebas de comportamiento, calcular el tiempo pasado en la zona de interacción (en segundos) y en la zona de esquina (en segundos) para cada ensayo como se muestra en Goto et al. 13. Juzgar la posición del ratón basado en el centro del ratón. </li><li> Calcular los puntajes de interacción social como 100 × (tiempo de interacción, con el objetivo) / (tiempo de interacción, sin objetivo), siguiendo los métodos publicados en Krishnan et al. 21. </li></ol></li></ol>

<ol>
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Nurse Pract. 6 (7), 546-550 (2010).</li><li>Dundas, B., Harris, M., Narasimham, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Psychogenic+Polydipsia+Review:+Etiology,+Differential,+and+Treatment.">Psychogenic Polydipsia Review: Etiology, Differential, and Treatment.</a> Curr. Psychiatry Rep. 9 (3), 236-241 (2007).</li><li>Tsumura, K., 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=Downregulation+of+AQP2+expression+in+the+kidney+of+polydipsic+STR/N+mice.">Downregulation of AQP2 expression in the kidney of polydipsic STR/N mice.</a> Am. J. Physiol. Renal Physiol. 290 (2), F478-F485 (2006).</li><li>Flores, 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=Schedule-Induced+Polydipsia:+Searching+for+the+Endophenotype+of+Compulsive+Behavior.">Schedule-Induced Polydipsia: Searching for the Endophenotype of Compulsive Behavior.</a> World J. Neurosci. 4, 253-260 (2014).</li><li>Cryan, J. F., Dinan, T. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mind-altering+microorganisms:+the+impact+of+the+gut+microbiota+on+brain+and+and+behaviour.">Mind-altering microorganisms: the impact of the gut microbiota on brain and and behaviour.</a> Nat. Rev. Neurosci. 13 (10), 701-712 (2012).</li></ol>

Los autores declaran que no tienen intereses financieros en competencia.

Hubo diferencias definitivas en el peso corporal entre sCSDS ratones y ratones sometidos a CSDS el protocolo CSDS estándar (5 a 10 min de contacto físico con los agresores por día) 19. Los ratones mostraron una mayor sCSDS BWG durante el periodo de estrés, mientras que los ratones estándar CSDS mostraron una disminución en el peso corporal durante el período de estrés 21,22,23. Hay una diferencia sustancial entre los dos protocolos en cuanto a la duración total del contacto físico con los...

Hay muchos tipos de eventos estresantes ocurren a través de las vidas de los seres humanos. El estrés excesivo a menudo conduce a consecuencias fisiológicas nocivos en los seres humanos y los animales. En los seres humanos, los acontecimientos estresantes son los principales factores de riesgo de precipitación de trastornos psiquiátricos como la depresión 1. Una Carga Global de Enfermedad de estudios indicó que la depresión es uno de los trastornos más discapacitantes en términos de años de vida ajustados por discapacidad (AVAD) y los años vividos con discapacidad 2. Además, la depresión representa la mayor proporción de AVAD suicidas 3. Las personas que sufren de depresión tienen dificultades para manejar sus vidas, y como consecuencia, su calidad de vida a menudo empeora. Por lo tanto, existe una fuerte necesidad de desarrollar productos terapéuticos eficaces para mejorar la calidad de vida de estos pacientes. Muchos estudios se han realizado en los trastornos depresivos mayores, y han puesto de manifiesto que la contribución genética a la enfermedad susceptibility es de aproximadamente 30-40%, que se explica por los efectos de múltiples loci de efectos pequeños 4. Debido a los complejos mecanismos patogénicos subyacentes depresión, la etiología detallada de la enfermedad sigue siendo difícil de alcanzar. Informes clínicos indican que hay subtipos de depresión como la depresión melancólica y atípico 5, que muestran una reducción y aumento del peso corporal, respectivamente 6. Aunque el 25-30% y el 15-30% de los pacientes con depresión representan características melancólicas y atípicos puros, respectivamente, la mayoría de ellos tienen características mixtas de ambos subtipos 7. Por lo tanto, la depresión mayor tiene una amplia gama de síntomas. Con el fin de encontrar biomarcadores y desarrollar terapias objetivas para los diversos tipos de depresión en los seres humanos, es importante establecer varios modelos animales diferentes de la depresión 8. Los modelos animales de depresión se han establecido usando varios métodos incluyendo aprendidoimpotencia, estrés leve crónico impredecible, y el estrés derrota sociales crónica (DCV) 9-12. Toyoda y colegas establecieron los modelos CSDS de ratas y ratones 13-17 con el fin de dilucidar el metabolismo y comportamientos que están asociados con la depresión. Dado que los modelos animales de depresión son evaluados por la validez aparente 18, el contexto en el que se establece el modelo es importante. Por otra parte, Golden et al. 19 informó los métodos para la creación de ratones DCV de detalle. Se sabe que las deficiencias en el comportamiento social de los ratones CSDS pueden ser recuperados por el tratamiento crónico, pero no por el tratamiento agudo, con antidepresivos, y que comparten síntomas similares a los de los pacientes con depresión en cuanto a la regulación de neurotrófico derivado del cerebro factor de 6. Goto et al. 13 desarrollaron anteriormente el estrés derrota social, subcrónica y leve (sCSDS) modelo de ratón mediante la modificación de los métodosde Golden et al. 19. Los ratones sCSDS muestran síntomas polydipsia- y hiperfagia como siguientes aumentos en el peso corporal y el contenido de agua incrementado cuerpo 13. En este informe, se proporciona el protocolo para establecer el modelo de ratón sCSDS y discutimos la utilidad de este modelo.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>single cage</td>
			<td>Charles River Laboratories Japan</td>
			<td></td>
			<td>width [W] &#215; depth [D] &#215; height [H] = 143 &#215; 293 &#215; 148 mm</td>
		</tr>
		<tr>
			<td>M cage</td>
			<td>Natsume Seisakusho</td>
			<td></td>
			<td>W &#215; D &#215; H = 220 &#215; 320 &#215; 135 mm</td>
		</tr>
		<tr>
			<td>Whiteflake</td>
			<td>Charles River Laboratories Japan</td>
			<td></td>
			<td>Wood-shaving chips made from spruce trees</td>
		</tr>
		<tr>
			<td>AIN-93G</td>
			<td>Oriental Yeast</td>
			<td></td>
			<td>purified-diet food pellets</td>
		</tr>
		<tr>
			<td>Kimtowel</td>
			<td>Nippon Paper Crecia Co.</td>
			<td></td>
			<td>Paper towels</td>
		</tr>
		<tr>
			<td>open-field arena</td>
			<td>O&#8217;Hara &#38; Co.</td>
			<td></td>
			<td>made of gray polyvinylchloride</td>
		</tr>
	</tbody>
</table>

a mouse model of subchronic and mild social defeat stress for understanding stress-induced behavioral and physiological deficits

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of depression is essential. Because there are several types of depression, various animal models are needed for a deeper understanding of the disorder. Previously, a mouse model of subchronic and mild social defeat stress (sCSDS) using a modified chronic social defeat stress (CSDS) paradigm was established. In the paradigm, to reduce physical injuries from aggressors, the duration of physical contact between the aggressor and a subordinate was reduced compared to in the original CSDS paradigm. sCSDS mice showed increased body weight gain, food intake, and water intake during the stress period, and their social behaviors were suppressed after the stress period. In terms of the face validity of the stress-induced overeating and overdrinking following the increased body weight gain, the sCSDS mice may show some features related to atypical depression in humans. Thus, a mouse model of sCSDS may be useful for studying the pathogenic mechanisms underlying depression. This protocol will help establish the sCSDS mouse model, especially for studying the mechanisms underlying stress-induced weight gain and polydipsia- and hyperphagia-like symptoms.

Para controlar el grado de estrés físico durante más de los períodos de 10 días, el número de picaduras de ataque por los ratones ICR se contó manualmente por un investigador. Figura 5A indica los valores individuales para el número de picaduras de ataque recibidos. Hubo una considerable variabilidad en la etapa temprana (aproximadamente 10 a 120 picaduras en día 1), pero esta variabilidad se redujo en la etapa posterior (aproximadamente 5-20 picaduras en día 10). La Figura 5B...

Watch this Scientific Journal Video about A Mouse Model of Subchronic and Mild Social Defeat Stress for Understanding Stress-induced Behavioral and Physiological Deficits at JoVE.com

A Mouse Model of Subchronic and Mild Social Defeat Stress for Understanding Stress-induced Behavioral and Physiological Deficits

Aquí, los métodos para el desarrollo de un modelo de ratón de estrés derrota social, subcrónica y leves se describen y se utilizan para investigar las características patogénicas de la depresión, incluyendo hyperphagia- y síntomas como polidipsia siguientes aumento del peso corporal.

Un modelo de ratón de subcrónica y leve estrés Derrota Social para Entender déficits conductuales y fisiológicos inducidos por el estrés

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of ...

a-mouse-model-subchronic-mild-social-defeat-stress-for-understanding

Research

JoVE Journal

Behavior

19.4K vistas.  Ibaraki University.  Aquí, los métodos para el desarrollo de un modelo de ratón de estrés derrota social, subcrónica y leves se describen y se utilizan para investigar las características patogénicas de la depresión, incluyendo hyperphagia- y síntomas como polidipsia siguientes aumento del peso corporal. 

Video: A Mouse Model of Subchronic and Mild Social Defeat Stress for Understanding Stress-induced Behavioral and Physiological Deficits

The Resident-intruder Paradigm: A Standardized Test for Aggression, Violence and Social Stress

This video publication explains in detail the experimental protocol of the resident-intruder paradigm in rats. This test is a standardized method to measure offensive aggression and defensive behavior in a semi natural setting. The most important behavioral elements performed by the resident and the intruder are demonstrated in the video and illustrated using artistic drawings. The use of the resident intruder paradigm for acute and chronic social stress experiments is explained as well. Finally, some brief tests and criteria are presented to distinguish aggression from its more violent and pathological forms.

This video shows the resident-intruder paradigm in rats. This test is a standardized method to measure offensive aggression, defensive behavior and violence in a semi-natural setting. The use of the paradigm for social stress experiments is explained as well.

El Paradigma Residente intruso: una prueba estandarizada para la agresión, la violencia y el estrés social

This video publication explains in detail the experimental protocol of the resident-intruder paradigm in rats. This test is a standardized method to ...

Investigación

Comportamiento

Using Chronic Social Stress to Model Postpartum Depression in Lactating Rodents

Exposure to chronic stress is a reliable predictor of depressive disorders, and social stress is a common ethologically relevant stressor in both animals and humans. However, many animal models of depression were developed in males and are not applicable or effective in studies of postpartum females. Recent studies have reported significant effects of chronic social stress during lactation, an ethologically relevant and effective stressor, on maternal behavior, growth, and behavioral neuroendocrinology. This manuscript will describe this chronic social stress paradigm using repeated exposure of a lactating dam to a novel male intruder, and the assessment of the behavioral, physiological, and neuroendocrine effects of this model. Chronic social stress (CSS) is a valuable model for studying the effects of stress on the behavior and physiology of the dam as well as her offspring and future generations. The exposure of pups to CSS can also be used as an early life stress that has long term effects on behavior, physiology, and neuroendocrinology.

This article describes the use of chronic resident intruder social stress as an ethologically relevant paradigm to model postpartum depression and anxiety in lactating rodents.

Usando estrés social crónico de Modelo depresión posparto en vacas roedores

Exposure to chronic stress is a reliable predictor of depressive disorders, and social stress is a common ethologically relevant stressor in both animals ...

Moderate Prenatal Alcohol Exposure and Quantification of Social Behavior in Adult Rats

Alterations in social behavior are among the major negative consequences observed in children with Fetal Alcohol Spectrum Disorders (FASDs). Several independent laboratories have demonstrated robust alterations in the social behavior of rodents exposed to alcohol during brain development across a wide range of exposure durations, timing, doses, and ages at the time of behavioral quantification. Prior work from this laboratory has identified reliable alterations in specific forms of social interaction following moderate prenatal alcohol exposure (PAE) in the rat that persist well into adulthood, including increased wrestling and decreased investigation. These behavioral alterations have been useful in identifying neural circuits altered by moderate PAE1, and may hold importance for progressing toward a more complete understanding of the neural bases of PAE-related alterations in social behavior. This paper describes procedures for performing moderate PAE in which rat dams voluntarily consume ethanol or saccharin (control) throughout gestation, and measurement of social behaviors in adult offspring.

The goal of the protocol presented here is to describe procedures to expose rats to moderate levels of alcohol during prenatal brain development and to quantify resulting alterations in social behavior during adulthood.

Moderada exposición prenatal al alcohol y cuantificación de la conducta social en ratas adultas

Alterations in social behavior are among the major negative consequences observed in children with Fetal Alcohol Spectrum Disorders (FASDs). Several ...

The Social Dimension of Stress: Experimental Manipulations of Social Support and Social Identity in the Trier Social Stress Test

In many situations humans are influenced by the behavior of other people and their relationships with them. For example, in stressful situations supportive behavior of other people as well as positive social relationships can act as powerful resources to cope with stress. In order to study the interplay between these variables, this protocol describes two effective experimental manipulations of social relationships and supportive behavior in the laboratory. In the present article, these two manipulations are implemented in the Trier Social Stress Test (TSST)&#8212;a standard stress induction paradigm in which participants are subjected to a simulated job interview. More precisely, we propose (a) a manipulation of the relationship between different protagonists in the TSST by making a shared social identity salient and (b) a manipulation of the behavior of the TSST-selection committee, which acts either supportively or unsupportively. These two experimental manipulations are designed in a modular fashion and can be applied independently of each other but can also be combined. Moreover, these two manipulations can also be integrated into other stress protocols and into other standardized social interactions such as trust games, negotiation tasks, or other group tasks.

Previous research on the social dimension of stress has focused on two important variables: social identity and social support. This protocol introduces an effective experimental manipulation of these two social variables and describes their implementation in a standard stress induction paradigm (Trier Social Stress Test).

La dimensión social del estrés: Manipulaciones experimentales de Apoyo Social e Identidad Social en el Trier Social Estrés Prueba

In many situations humans are influenced by the behavior of other people and their relationships with them. For example, in stressful situations ...

An Unpredictable Chronic Mild Stress Protocol for Instigating Depressive Symptoms, Behavioral Changes and Negative Health Outcomes in Rodents

Chronic, unresolved stress is a major risk factor for the development of clinical depression. While many preclinical models of stress-induced depression have been reported, the unpredictable chronic mild stress (UCMS) protocol is an established translationally-relevant model for inducing behavioral symptoms commonly associated with clinical depression, such as anhedonia, altered grooming behavior, and learned helplessness in rodents. The UCMS protocol also induces physiological (e.g., hypercortisolemia, hypertension) and neurological (e.g., anhedonia, learned helplessness) changes that are clinically associated with depression. Importantly, UCMS-induced depressive symptoms can be ameliorated through chronic, but not acute, treatment with common SSRIs. As such, the UCMS protocol offers many advantages over acute stress protocols or protocols that utilize more extreme stressors. Our protocol involves randomized, daily exposures to 7 distinct stressors: damp bedding, removal of bedding, cage tilt, alteration of light/dark cycles, social stresses, shallow water bath, and predator sounds/smells. By subjecting rodents 3-4 hr daily to these mild stressors for 8 weeks, we demonstrate both significant behavioral changes and poor health outcomes to the cardiovascular system. This approach allows for in-depth interrogation of the neurological, behavioral, and physiological alterations associated with chronic stress-induced depression, as well as for testing of new potential therapeutic agents or intervention strategies.

The unpredictable chronic mild stress (UCMS) protocol is a validated method for studying behavioral and physiological changes associated with chronic stress and depressive symptoms. Eight weeks of imposition of the UCMS protocol induces behavioral changes and poor health outcomes in rodents of either gender.

Un protocolo de estrés leve crónico impredecible para los síntomas depresivos, instigar cambios de comportamiento y los resultados de salud negativos en los roedores

Chronic, unresolved stress is a major risk factor for the development of clinical depression. While many preclinical models of stress-induced depression ...

Detecting Behavioral Deficits in Rats After Traumatic Brain Injury

With the increasing incidence of traumatic brain injury (TBI) in both civilian and military populations, TBI is now considered a chronic disease; however, few studies have investigated the long-term effects of injury in rodent models of TBI. Shown here are behavioral measures that are well-established in TBI research for times early after injury, such as two weeks, until two months. Some of these methods have previously been used at later times after injury, up to one year, but by very few laboratories. The methods demonstrated here are a short neurological assessment to test reflexes, a Beam-Balance to test balance, a Beam-Walk to test balance and motor coordination, and a working memory version of the Morris water maze that can be sensitive to deficits in reference memory. Male rats were handled and pre-trained to neurological, balance, and motor coordination tests prior to receiving parasagittal fluid percussion injury (FPI) or sham injury. Rats can be tested on the short neurological assessment (neuroscore), the beam-balance, and the Beam-Walk multiple times, while testing on the water maze can only be done once. This difference is because rats can remember the task, thus confounding the results if repeated testing is attempted in the same animal. When testing from one to three days after injury, significant differences are detected in all three non-cognitive tasks. However, differences in the Beam-Walk task were not detectable at later time points (after 3 months). Deficits were detected at 3 months in the Beam-Balance and at 6 months in the neuroscore. Deficits in working memory were detected out to 12 months after injury, and a deficit in a reference memory first appeared at 12 months. Thus, standard behavioral tests can be useful measures of persistent behavioral deficits after FPI.

The goal of the behavioral tests presented here is to detect functional deficits in rats after traumatic brain injury. Four specific tests are presented that detect deficits in behaviors to reflect the damage to specific brain areas at times extending to one year after injury.

Detección de déficits conductuales en ratas después de la lesión cerebral traumática

With the increasing incidence of traumatic brain injury (TBI) in both civilian and military populations, TBI is now considered a chronic disease; however, ...

The Unpredictable Chronic Mild Stress Protocol for Inducing Anhedonia in Mice

Depression is a highly prevalent and debilitating condition, only partially addressed by current pharmacotherapies. The lack of response to treatment by many patients prompts the need to develop new therapeutic alternatives and to better understand the etiology of the disorder. Pre-clinical models with translational merits are rudimentary for this task. Here we present a protocol for the unpredictable chronic mild stress (UCMS) method in mice. In this protocol, adolescent mice are chronically exposed to interchanging unpredictable mild stressors. Resembling the pathogenesis of depression in humans, stress exposure during the sensitive period of mice adolescence instigates a depressive-like phenotype evident in adulthood. UCMS can be used for screenings of antidepressants on the variety of depressive-like behaviors and neuromolecular indices. Among the more prominent tests to assess depressive-like behavior in rodents is the sucrose preference test (SPT), which reflects anhedonia (core symptom of depression). The SPT will also be presented in this protocol. The ability of UCMS to induce anhedonia, instigate long-term behavioral deficits and enable reversal of these deficits via chronic (but not acute) treatment with antidepressants strengthens the protocol&#39;s validity compared to other animal protocols for inducing depressive-like behaviors.

Here we present the unpredictable chronic mild stress protocol in mice. This protocol induces a long-term depressive-like phenotype and enables to assess the efficacy of putative antidepressants in reversing the behavioral and neuromolecular depressive-like deficits.

El protocolo de estrés leve crónico impredecible para inducir la Anhedonia en ratones

Depression is a highly prevalent and debilitating condition, only partially addressed by current pharmacotherapies. The lack of response to treatment by ...

Stress-Enhanced Fear Learning, a Robust Rodent Model of Post-Traumatic Stress Disorder

Fear behaviors are important for survival, but disproportionately high levels of fear can increase the vulnerability for developing psychiatric disorders such as post-traumatic stress disorder (PTSD). To understand the biological mechanisms of fear dysregulation in PTSD, it is important to start with a valid animal model of the disorder. This protocol describes the methodology required to conduct stress-enhanced fear learning (SEFL) experiments, a preclinical model of PTSD, in both rats and mice. SEFL was developed to recapitulate critical aspects of PTSD, including long-term sensitization of fear learning caused by an acute stressor. SEFL uses aspects of Pavlovian fear conditioning but produces a distinct and robust sensitized fear response far greater than normal conditional fear responses. The trauma procedure involves placing a rodent in a conditioning chamber and administering 15 unsignaled shocks randomly distributed over 90 minutes (for rat experiments; for mouse experiments, 10 unsignaled shocks randomly distributed over 60 minutes are used). On day 2, rodents are placed in a novel conditioning context where they receive a single shock; then, on day 3 they are placed back in the same context as on day 2 and tested for changes in freezing levels. Rodents that previously received the trauma display enhanced levels of freezing on the test day compared to those that received no shocks on the first day. Thus, with this model, a single highly stressful experience (the trauma) produces extreme fear of the stimuli associated with the traumatic event.

Here we describe the detailed methodology required to conduct stress-enhanced fear learning (SEFL) experiments, a preclinical model of post-traumatic stress disorder, in both rats and mice. The model utilizes aspects of Pavlovian fear conditioning and freezing as an index of enhanced fear in rodents.

Miedo estrés mayor aprendizaje, un modelo de roedor robusto del trastorno por estrés postraumático

Fear behaviors are important for survival, but disproportionately high levels of fear can increase the vulnerability for developing psychiatric disorders ...

A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants

The complex lifestyle, evolutionary history of advanced cooperation, and disease defenses of leaf-cutting ants are well studied. Although numerous studies have described the behaviors connected with disease defense, and the associated use of chemicals and antimicrobials, no common visual reference has been made. The main aim of this study was to record short clips of behaviors involved in disease defense, both prophylactically and directly targeted towards an antagonist of the colony following infection. To do so we used an infection experiment, with sub-colonies of the leaf-cutting ant species Acromyrmex echinatior, and the most significant known pathogenic threat to the ants&#39; fungal crop (Leucoagaricus gongylophorus), a specialized pathogenic fungus in the genus Escovopsis. We filmed and compared infected and uninfected colonies, at both early and more advanced stages of infection. We quantified key defensive behaviors across treatments and show that the behavioral response to pathogen attack likely varies between different castes of worker ants, and between early and late detection of a threat. Based on these recordings we have made a library of behavioral clips, accompanied by definitions of the main individual defensive behaviors. We anticipate that such a guide can provide a common frame of reference for other researchers working in this field, to recognize and study these behaviors, and also provide greater scope for comparing different studies to ultimately help better understand the role these behaviors play in disease defense.

We present a visual guide to disease defense behaviors in leaf-cutting ants, with individual clips and accompanying definitions, illustrated in an experimental infection scenario. Our main aim is to help other researchers recognize key defensive behaviors and to provide a common understanding for future research in this field.

Una guía Visual para el estudio de las defensas contra comportamiento patógeno ataca en hormigas cortadoras

The complex lifestyle, evolutionary history of advanced cooperation, and disease defenses of leaf-cutting ants are well studied. Although numerous studies ...

Nest Building Behavior as an Early Indicator of Behavioral Deficits in Mice

Nest building is an innate behavior in male and female rodents, even when raised in laboratory settings. As such, many researchers provide rodents synthetic and/or natural materials (such as twine, tissue, cotton, paper, and hay) as a gauge of their overall well-being and as an ancillary assessment to predict the possible decline in cognition. Typically, changes in nesting behaviors, such as failure to create a nest, indicate a change in health or welfare. In addition, nesting behavior is sensitive to many environmental and physiological challenges, as well as many genetic mutations underlying pathological disease states. The following protocol describes a nesting behavior paradigm that explores the usage of four types of nesting material. In addition, the protocol utilizes intraclass correlations to demonstrate that inter-rater reliability is higher when nests are constructed out of shredded paper compared to other common nesting materials such as cotton squares, paper twists, and soft cob bedding. The chosen methodology and statistical considerations (i.e., intraclass correlation) for this assay may be of interest for those conducting experiments assessing the quality of living of mice.&#160;

Here, we present a protocol to quantify nest building behavior in mice, which is known to be impaired in several neurological disorders and diseases. This protocol examines the utility of four materials and offers the opportunity to quantify the rater agreement in scoring, improving the validity and reliability of the assay.