X-PloRat: A Software for Scoring Animal Behavior in Enclosed Spaces / X-PloRat: Software para o Registro do Comportamento em Espaços Confinados

ABSTRACT The present technical note introduces the X-PloRat, a software for the scoring of animal location, displacement, and other behavioral properties, in enclosed spaces. The X-PloRat offers a variety of data reports and can be used for training students in behavioral observation and in validating other kinds of scoring procedures.

RESUMO A presente nota técnica apresenta o X-PloRat, um software que permite o registro da localização, deslocamento e outras propriedades do comportamento animal em espaços confinados. O X-PloRat oferece uma grande variedade de relatórios e pode ajudar no treinamento de estudantes em observação do comportamento e também na validação de outros tipos de registros.

Discrimination of anxiety- versus panic-like behavior in the wall lizard Tropidurus oreadicus

A behavioral test battery is proposed for wall lizards (Tropidurus oreadicus) that consists of inducing tonic immobility (TI) followed by post-TI behavioral scoring. After the induction of TI, the usual behavioral sequence was flight followed by freezing and tongue-flicking and/or thigmotaxis, with flight being more probable than freezing. These sequences were not observed after restraint in a normal upward position (which induced freezing but not TI) or after handling (which increased the probability of tongue-flicking). Alprazolam and imipramine selectively decreased the duration of TI as well as the following flight and freezing behavior. Tongue-flicking was increased by diazepam and alprazolam, whereas fluoxetine decreased it. Finally, thigmotaxis was reduced by diazepam, alprazolam, and imipramine but increased by fluoxetine. These results suggest that panic and anxiety can be discriminated pharmacologically in wall lizards...

The effects of diazepam on the elevated T-maze are dependent on the estrous cycle of rats

In order to determine the modulation of anxiolytic and panicolytic-like effects of diazepam by the hormonal cycle of female rats, male and female rats - the latter divided per estrous cycle phase (estrus, diestrus, metaestrus and proestrus) - were tested in the elevated T-maze, a behavioral model of panic and anxiety. Diazepam (0.5, 1.0 and 2.0 mg/kg) or saline solution was injected in individual animals that were submitted to one session in the elevated T-maze 25 min after drug/saline administration. The test consisted of three avoidance trials and one escape trial, separated by a 30 s interval, during which the animals were isolated in individual cages. The avoidance trials began with the animal being placed at the end of the maze's enclosed arm. The time necessary for the animal to leave the central square was considered as the response's latency. The trials that exceeded 300 s were considered as failures. Results demonstrate a decrease in the effects of diazepam in inhibitory avoidance (anxiety) trials in females in diestrus and proestrus, but no relation of gender or estrous cycle on diazepam effects on escape trials (fear). The results support the hypothesis that down-regulation of GABA A receptors by activation of nuclear estrogen receptors and induction of PKC-mediated GABA A receptor phosphorylation by activation of surface estrogen receptors in raphe neurons underlie the modulation of diazepam sensitivity by estrogen.

Previous spatial learning is required for the development of place preference in rats following chronic administration of and withdrawal from morphine

The positive reinforcing properties of addictive drugs have a primary role in the development of drug dependence. In the field of opiates, great attention has been given to this phenomenon, as well as to the negative properties eliciting craving and inducing relapse during withdrawal. This study was designed to evaluate whether elevated plus-maze (EPM) experienced rats withdrawn from low doses of subcutaneous (s.c.) morphine (10 mg/kg), in which a high anxiety level is the most prominent withdrawal symptom, acquire place preference when submitted to a conflict paradigm in which drug effects are paired with an aversive context: the distal part of the open arms of an EPM. Both the anxiety test and place preference conditioning were measured in the same apparatus, a biased version of the plus-maze. In order to verify the influence of previous EPM spatial learning on the performance of morphine-withdrawn rats, half the animals in this study experienced the EPM prior to treatment. Additional groups were also tested under the influence of morphine effects. The effects of the treatments were quantified through the analysis of three types of measures: anxiety was inferred from the use of the conventional measures (percentage of entries and time spent in the open-arms) and risk-assessment behaviours (frequency of stretched-attending postures - SAP, and time spent at the centre of the maze). Place preference conditioning was evaluated through analysis of the number of entries, total time spent and distance run in the open-arm extremities, which is where the animals were conditioned. The number of closed-arm entries was taken as an index of locomotor activity. Our results showed that (i) EPM naïve rats pre-treated with morphine did not develop place preference, behaving like control rats; (ii) rats that had previous experience in the EPM showed no changes in open-arm avoidance on the second exposure, when compared with rats naïve for this condition; (iii) previous spatial learning of the EPM contextual cues was, in fact, a requirement for anxiety-inducing place preference for the open-arms in morphine-withdrawn rats and, (iiii) conditioned place preference was achieved both in rats under the effects of morphine and in withdrawal, probably through the influence of the positive or negative reinforcing effects promoted by the presence or absence of the drug in the central nervous system.

Influence of gender and estrous cycle in the forced swim test in rats

The present work aimed at studying the influence of the estrous cycle in the forced swim test, an animal model of depression. For this, 44 male and female Wistar rats were divided into five groups according to the hormonal state in the first day of the study: metaestrus (N = 12), diestrus (N = 8), proestrus (N = 7), estrous (N = 6) and males (N = 11). They were housed in groups of five, with water and food ad libitum under a 12/12 h light/dark cycle. Females were screened daily for the estrous cycle. The animals were subjected to two swimming sessions in a glass cylinder with water up to 15 cm at 28±2º C. The data of the first five minutes of a 15-min first session were compared to those of a 5-min second session 24 h later. The results indicate that the latency to the first immobility was substantially reduced in the second session and was longer for females in diestrus and proestrus in the first session. The results also indicate that females in diestrus and proestrus exhibited less immobility than males in the first session; females in diestrus also exhibited less immobility than females in metaestrus. Females in metaestrus and diestrus, as well as males, did not present the decrease in total immobility times in the second session. The present results are analyzed in terms of differential effects of progesterone and estrogen on a learning component and an affective component.

Preference for the light compartment of a light/dark cage does not affect rat exploratory behavior in the elevated plus-maze

The are few reports on the relationship between elevated plus-maze and effects of maintenance conditions in the days prior to the test. Previously, we have demonstrated that being forcibly in total dark or in light for four days does not alter exploratory behavior in the plus-maze. The present study aimed at recording illumination level preferences in rats using a box with light and dark compartments (or another with two light compartments) and the behavioral effect of this choice on the plus-maze. The rats allowed to express their preference to remain in one particular level of illumination tended to stay initially in the dark compartment and gradually preferred to remain in the light compartment. When tested in the elevated plus-maze there were no effects in comparison to controls kept in commercial cages.

Ansiedad y mied:: su valor adaptativoy maladaptacioess / Fear and nxiety:: adaptive value and maladaptations

The set of answers emitted by the organisms in response to a real or potential danger is called the Anxiety State. This state, of evolutionary importance, appears when a strong danger or risk is detected, and in response to ambiguous threat stimuli that could be of innate or learned nature. A low level of anxiety is beneficial for the animals as a fundamental resource of protection of the individual against physical and social dangers. The neural basis responsible by such states would be the oldest cerebral areas, preserved in many species, that are crucial for the control of the emotions, and whosemalfunctions lead to mood disorders. Many experimental models have been developed to help the study of behaviors and neural basis of the anxiety state, providing tools that collaborate not only to the therapeutics of pathologies, but also to the better understanding of the world of the emotions.

El conjunto de respuestas emitidas por diferentes especies frente a un peligro real o potencial se conoce como Estado de Ansiedad. Este estado, de importancia evolutiva para las especies, aparece cuando se detecta un peligro o amenaza o ante la presencia de estímulos ambiguos, innatos o aprendidos, que indican una amenaza. Así, un determinado nivel de ansiedad es benéfico para los animales, siendo un recurso fundamental de protección contra peligros físicos y sociales. Los substratos neurales responsables por tales estados, corresponden a áreas cerebrales antiguas, preservadas en muchas especies y críticas para el control de las emociones que al sufrir alteraciones en su funcionamiento producen disturbios del comportamiento. Diversos modelos experimentales se han desarrollado para estudiar los componentes conductuales y sustratos neurales implicados en el estado de ansiedad y su utilización ya está suministrando herramientas para complementar la comprensión de diversas patologías y conocimiento del mundo de las emociones.

O papel da visão na aversão aos espaços abertos no labirinto em cruz elevado / The role of vision in the aversion to the open spaces in the elevated plus-maze

O labirinto em cruz elevado é um dos modelos mais usados no estudo da ansiedade, medo e fármacos que alteram esses estados. Apesar da simplicidade aparente do modelo, diversos são os fatores que afetam o comportamento de ratos submetidos a esse modelo. Além disso, não se conhece exatamente quais os estímulos ambientais são os desencadeadores da aversão nesse modelo. O presente trabalho sugere que, em estudos onde os estímulos auditivos e olfativos são controlados, a aversão em ratos é desencadeada pela visão. A hipótese de trabalho é que os mecanismos mediadores da aversão (e estados emocionais concomitantes) são deflagrados pela entrada de luz e pela formação de imagens na retina dos animais. Para fundamentar essas hipóteses complementares, vários experimentos são analisados, cujos resultados favorecem uma, outra ou ambas as hipóteses. Finalmente, resultados obtidos com marcação da proteína c-Fos fornecem evidência neurofuncional que apóia as duas hipóteses sugeridas

Papel da luminosidade do biotério no comportamento do rato no labirinto em cruz elevado / Role of vivarium illumination in rat behavior in the elevated plus-maze

Há pouca informação sobre o efeito dos ambientes onde os ratos são mantidos antes de testes. Para investigar o efeito da iluminação do biotério, ratos Wistar machos foram submetidos a um período de 96 h de iluminação contínua, escuridão contínua ou um ciclo claro escuro de 12:12 h e testados no labirinto em cruz elevado em uma sala iluminada (150 lux) ou escura (0 lux). Os resultados mostram que nem a iluminação contínua nem a escuridão contínua do biotério afetam o comportamento dos ratos, quando comparados aos sujeitos mantidos no ciclo claro-escuro de 12 h. A condição de luminosidade durante o teste, no entanto, foi importante: independentemente da condição de iluminação do biotério, os animais testados no escuro exploraram mais os braços abertos do labirinto, um resultado já relatado na literatura e interpretado como diminuição da ansiedade nesse aparato.

There is little information about the environments where rats are kept before being tested. In order to investigate the role of vivarium illumination, male Wistar rats were submitted to a 96-h period of continuous illumination, continuous dark or a 12:12 h light/dark cycle and tested in the elevated plus-maze in a lit (150 lux) or a dark room (0 lux). Results showed that neither vivarium illumination nor darkness for 96 h altered the rats' behavior in comparison to that of rats kept under the 12-h light/dark cycle. Luminosity during the test, however, was important: no matter what the vivarium illumination was, rats tested in the dark room explored more the open arms of the maze, an already reported result which is interpreted as decreased anxiety in this apparatus.

Preference of goldfish (Carassius auratus) for dark places

Visando determinar a preferência por ambientes claros ou escuros, peixes dourados (Carassius auratus) foram submetidos a um teste num aquário em que podiam sair de um compartimento central indo seja para um compartimento preto, seja para um compartimento branco. Registrou-se (1) o primeiro compartimento escolhido,(2) a freqüência de entradas em cada compartimento, e (3) o tempo gasto neles. Os resultados mostram que, nas condições experimentais, C. auratus tem preferência significativa pelo escuro, uma característica relevante para o desenvolvimento de um modelo experimental de ansiedade com esta espécie

Influências do ciclo estral sobre o desempenho de ratos no labirinto em cruz elevado / Effects of Estrous cycle on the behavior in the elevated plus maze

O Labirinto em cruz elevado é um dos mais populares modelos animais para estudo da ansiedade. Esta pode ser influenciada por fatores fisiológicos como o ciclo hormonal das fêmeas. O objetivo do presente trabalho foi investigar as influências do ciclo estral no comportamento exploratório de ratas no Labirinto em cruz elevado. Setenta animais (13 machos e 61 fêmeas)foram utilizados. As fêmeas tiveram seu ciclo estral mapeado e os animais foram testados segundo a fase do ciclo em que se encontravam, gerando, além do grupo Machos, 3 grupos de fêmeas: Proestro (N=23), Estro (N=19)e Diestro (N=19). Cada animal foi submetido a uma única sessão de 5 min. no Laboratório. Os resultados indicam diferenças significativas entre o grupo de machos e o de fêmeas no Diestro quanto à porcentagem de tempo gasto nos braços abertos, mas não quanto à porcentagem de entradas nos mesmo