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Socialization, and its modulation by sex, on the development and recovery of activity-based anorexia in rats

e-cienciaDatos, Repositorio de Datos del Consorcio Madroño
  • Martínez-Herrada, Antonio
  • de Paz, Ana
  • Pellón, Ricardo
<p><b>Description of the project</b></p>

<p>Activity-based anorexia (ABA) is the main animal model used in the laboratory to study the role of restricted food intake and the central importance of excessive physical activity on the severe weight loss observed in the human disorder of anorexia nervosa. The procedure is usually carried out by individual isolation of animals, usually rats or mice, in a cage equipped with an activity wheel that they can access 23 hours a day and where food intake is limited to 1 h per day. Under these conditions, animals progressively perform more exercise despite eating less, and they lose weight until death unless they are withdrawn from the procedure. It is known that the impact that social stress (e.g. isolation) exerts on health is common to humans and other social mammals, where it has been observed that adverse social consequences cause pathologies with patterns parallel to those that occur in humans. In the present study, the animals’ social condition was manipulated to observe the effect of socialization in ABA development, its recovery, and the possible different influence of the variable sex on ABA development. The results allow us to deepen our knowledge of this phenomenon and how variables related to the social environment could affect the development and recovery of anorexia nervosa, in the hope that better prevention and therapy will be given to the patients that need them.</p>, <p><b>Description of the dataset</b></p>
<p>Dataset contains daily measurements of weight (percentage in relation to weight on day 0), food intake (number of grams of food consumed), food anticipatory activity (FAA) (number of wheel turns during the 2 hours before food time), postprandial activity (PPA) (number of wheel turns during the 2 hours after food time), total activity (FAA+PPA), activity distribution (number of wheel turns in each of the 1-minute intervals in which time of wheel access was divided), the days that each rat remained in the procedure until reached withdrawal criteria (survival), and the days necessary to recover the initial weight of each rat. The data were obtained from the 8 groups of rats in the experiment, with n = 10 subjects per group.</p>, <p><b>Methodology</b></p>

<p>The methodology of this study was experimental. The subjects were 80 Wistar Han rats 4 or 5 weeks old. After one week of quarantine and 4 days of acclimatization, the animals were semi-randomly assigned to the groups in a 2x2x2 design. The independent variables were: sex (male/female), social condition (individualization/group), and access to a running wheel (yes/no). Dependent variables were: 1) the percentage of weight, 2) grams of food intake, 3) the number of wheel turns during FAA and PPA, 4) the number of total wheel turns (FAA+PPA), 5) the number of days until reach withdrawal criteria, and 6) the number of days it took each withdrawn rat to regain its body weight in session 0.</p>

<p>Daily weight and food intake were manually recorded in an Excel datasheet to calculate the values of independent variables. The percentage of weight loss was calculated as the bodyweight of an animal in a particular day divided for its initial weight on session 0 and multiplied by 100. Total food consumed was calculated as the amount of food supplied minus the amount of food leftover. The number of wheel turns in FAA and PPA was automatically recorded through a MED PC IV program in individual *.txt files per subject and day. The distribution of activity was registered in 1-minute intervals. These measures were repeated during the fifteen days that the experiment lasted. The number of days to withdrawal was calculated as the number of days from session 0 to the day that a rat's weight was equal to or less than 75% of its initial weight. The number of days to recovery was calculated from the withdrawal day to the day the animal's weight was equal to or greater than its weight at session 0.</p>

</p>The Excel *.xlsx files has been saved as CSV UTF-8 (coma-separated values) (*.csv)</p>

Behavior Stability and Individual Differences in Pavlovian Extended Conditioning

Digital.CSIC. Repositorio Institucional del CSIC
  • Calcagni, Gianluca
  • Caballero-Garrido, E.
  • Pellón, R.
20 pags., 8 figs., 7 tabs., How stable and general is behavior once maximum learning is reached? To answer this question and understand post-acquisition behavior and its related individual differences, we propose a psychological principle that naturally extends associative models of Pavlovian conditioning to a dynamical oscillatory model where subjects have a greater memory capacity than usually postulated, but with greater forecast uncertainty. This results in a greater resistance to learning in the first few sessions followed by an over-optimal response peak and a sequence of progressively damped response oscillations. We detected the first peak and trough of the new learning curve in our data, but their dispersion was too large to also check the presence of oscillations with smaller amplitude. We ran an unusually long experiment with 32 rats over 3,960 trials, where we excluded habituation and other well-known phenomena as sources of variability in the subjects' performance. Using the data of this and another Pavlovian experiment by Harris et al. (2015), as an illustration of the principle we tested the theory against the basic associative single-cue Rescorla–Wagner (RW) model. We found evidence that the RW model is the best non-linear regression to data only for a minority of the subjects, while its dynamical extension can explain the almost totality of data with strong to very strong evidence. Finally, an analysis of short-scale fluctuations of individual responses showed that they are described by random white noise, in contrast with the colored-noise findings in human performance., The experiment was run at the Animal
Behavior Lab, Departamento de Psicología Básica I, Facultad
de Psicología, Universidad Nacional de Educación a Distancia,
Madrid, Spain, and was supported by grant PSI2016-80082-
P from Ministerio de Economía y Competitividad, Secretaría
de Estado de Investigación, Desarrollo e Innovación, Spanish
Government (RP).

Mutual facilitation between activity-based anorexia and schedule-induced polydipsia in rats

Digital.CSIC. Repositorio Institucional del CSIC
  • Labajos, María José
  • Calcagni, Gianluca
  • Pellón, Ricardo
19 pags., 8 figs., 3 tabs., The objective of this study was to evaluate the possible relationship between drinking (licks) in the schedule-induced polydipsia (SIP) phenomenon and running (turns in the wheel) in the activity-based anorexia (ABA) one. Within-subjects counterbalanced experiments were designed with male Wistar rats which underwent both behavioral procedures; half of them performed the ABA procedure first and the other half the SIP procedure first. In Experiment 1, the initial development of ABA facilitated the subsequent acquisition of SIP, whereas the first acquisition of SIP retarded the subsequent development of ABA. Given that SIP exposure implied food restriction, it could be that adaptation to the food regime contributed to lowering ABA manifestation. Thus, Experiment 2 was carried out in exactly the same way as Experiment 1, with the exception that animals which first went through SIP prior to undergoing the ABA procedure had no food restriction. In this case, both ABA and SIP as first experiences facilitated the further development of SIP and ABA, respectively. This suggests that running in ABA may be functionally similar to drinking in SIP; therefore, both behaviors can be thought of as induced by the schedule/regime of intermittent food availability., The authors wish to thank the funding from Spanish government grants PSI2011-29399 and PSI2016-
80082-P., Peer reviewed