Impact of Fluoxetine on Behavioral Invigoration of Appetitive and Aversively Motivated Responses: Interaction With Dopamine Depletion

Impaired behavioral activation and effort-related motivational dysfunctions like fatigue and anergia are debilitating treatment-resistant symptoms of depression. Depressed people show a bias towards the selection of low effort activities. To determine if the broadly used antidepressant fluoxetine can improve behavioral activation and reverse dopamine (DA) depletion-induced anergia, male CD1 mice were evaluated for vigorous escape behaviors in an aversive context (forced swim test, FST), and also with an exercise preference choice task [running wheel (RW)-T-maze choice task]. In the FST, fluoxetine increased active behaviors (swimming, climbing) while reducing passive ones (immobility). However, fluoxetine was not effective at reducing anergia induced by the DA-depleting agent tetrabenazine, further decreasing vigorous climbing and increasing immobility. In the T-maze, fluoxetine alone produced the same pattern of effects as tetrabenazine. Moreover, fluoxetine did not reverse tetrabenazine-induced suppression of RW time but it reduced sucrose intake duration. This pattern of effects produced by fluoxetine in DA-depleted mice was dissimilar from devaluing food reinforcement by pre-feeding or making the food bitter since in both cases sucrose intake time was reduced but animals compensated by increasing time in the RW. Thus, fluoxetine improved escape in an aversive context but decreased relative preference for active reinforcement. Moreover, fluoxetine did not reverse the anergic effects of DA depletion. These results have implications for the use of fluoxetine for treating motivational symptoms such as anergia in depressed patients

Preference for Exercise vs. More Sedentary Reinforcers: Validation of an Animal Model of Tetrabenazine-Induced Anergia

Physical activities can have intrinsic motivational or reinforcing properties. The choice to engage in voluntary physical activity is undertaken in relation to the selection of other alternatives, such as sedentary behaviors, drugs, or food intake. The mesolimbic dopamine (DA) system plays a critical role in behavioral activation or exertion of effort, and DA antagonism or depletion induces anergia in effort-based decision-making tasks. However, little is known about the neural mechanisms underlying the decision-making processes that establish preferences for sedentary vs. activity-based reinforcers. In the present work with male CD1 mice, we evaluated the effect of tetrabenazine (TBZ), a DA-depleting agent, on a three-choice T-maze task developed to assess preference between reinforcers with different behavioral activation requirements and sensory properties [i.e., a running wheel (RW) vs. sweet pellets or a neutral nonsocial odor]. We also studied the effects of TBZ on the forced swim test (FST), which measures climbing and swimming in a stressful setting, and on anxiety tests [dark-light (DL) box and elevated plus maze (EPM)]. In the three-choice task, TBZ reduced time running in the wheel but increased time spent consuming sucrose, thus indicating reduced activation but relatively intact sucrose reinforcement. The effect of TBZ was not mimicked by motivational manipulations that change the value of the reinforcers, such as making the RW aversive or harder to move, food-restricting the animals, inducing a binge-like eating pattern, or introducing social odors. In the FST, TBZ decreased time climbing (most active behavior) and increased immobility but did not affect anxiety in the DL or EPM. These results indicate that the three-choice T-maze task could be useful for assessing DA modulation of preferences for exercise based on activation and effort requirements, differentiating those effects from changes in preference produced by altering physical requirements, food restriction state, and stress during testing

Mecanismos neuroenzimáticos implicados en la regulación de las conductas inducidas por etanol: El papel de la catalasa cerebral

Manipulaciones farmacológicas para la regulación de la actividad del enzima catalasa y sus repercusiones en la locomoción y la narcosis inducidas por alcohol en ratones

Mecanismos neuroenzimáticos implicados en la regulación de las conductas inducidas por etanol: El papel de la catalasa cerebral

Manipulaciones farmacológicas para la regulación de la actividad del enzima catalasa y sus repercusiones en la locomoción y la narcosis inducidas por alcohol en ratones

Editorial: Ethanol, its active metabolites, and their mechanisms of action: Neurophysiological and behavioral effects

Ethanol, the main psychopharmacologically active ingredient of alcoholic drinks, represents a paradigmatic example of a research subject intrinsically able to perpetually self-generate interdisciplinary cutting-edge investigations.This eBook was inspired by the aim of providing an up-to-date characterization of the diverse effects of ethanol, of the possible mechanisms of action on different intracellular systems as well as of the hypothesized actions of ethanol and/or its metabolites on various neurotransmitters and neuromodulators.Indeed, the eBook provides a factual example of an excellent synthesis on the complex relationship between ethanol and its main biologically active metabolites (Chapter 1), on the behavioral and molecular consequences of early exposure to them (Chapter 2), on the recent proposals, advanced by the preclinical research, for new therapeutic approaches to distinct aspects of alcoholism (Chapter 3) and on the most recent and original preclinical evidence of the interactions between ethanol and/or its metabolites and the dopaminergic, adenosinergic and endocannabinoidergic systems (Chapter 4).Overall we believe that this eBook accomplishes its main goals of widening the perspective on this research subject and offering the readership a newer and, simultaneously, up-to-date and comprehensive scenery on ethanol’s and ethanol's active metabolites neurophysiological and behavioral effects

The development of Digital Teaching Competence in Higher Education. A systematic review of the literature

El presente artículo tiene como objetivo presentar los resultados de una Revisión Sistemática de Literatura sobre los niveles de desarrollo de la Competencia Digital Docente en Educación Superior. Se procedió a seleccionar artículos tomando como base criterios de inclusión, eventos de interés y palabras clave, empleadas en los motores de búsqueda de tres bases de datos: Redalyc, Scopus y ERIC, incluyendo estudios en español y en inglés realizados entre los años 2015 y 2021. Se trabajó a través de una metodología que dividió el proceso en cuatro etapas en las cuales se realizó una minuciosa selección de artículos, empleando la Rúbrica COMDID y la Declaración PRISMA 2020. Basados en esta modalidad, se describieron hallazgos y niveles de desarrollo de la CDD, lo cual posibilitó la obtención de resultados de la revisión en función de las dimensiones e indicadores de la Rúbrica COMDID para los 47 artículos seleccionados. Se identificaron relatos de experiencias con TIC describiendo un escenario ideal, pero donde no se concretan los niveles más altos en el desarrollo de la CDD, y sin intervención didáctica en las prácticas educativas institucionales de los docentes, para los niveles expertos o transformadores.This article aims to present the results of a Systematic Literature Review on the level development of Teaching Digital Competence in Higher Education. Articles were selected based on inclusion criteria, events of interest and keywords, used in the search engines of three databases: Redalyc, Scopus and ERIC, including studies in Spanish and English carried out between 2015 and 2015. 2021. We worked through a methodology that divided the process into four stages in which a thorough selection of articles was carried out, using the COMDID Rubric and the PRISMA 2020. Through this methodology, findings and levels of development of the CDD were described, which made it possible to obtain the results of the review based on the dimensions and indicators of the COMDID Rubric for the 47 selected articles. Reports of experiences with ICT were identified, describing an ideal scenario, but where the highest levels in the development of CDD are not materialized, and without didactic intervention in the institutional educational practices of teachers at the expert or transformative levels

Choosing voluntary exercise over sucrose consumption depends upon dopamine transmission: effects of haloperidol in wild type and adenosine A_2AKO mice

Rationale Mesolimbic dopamine (DA) regulates behavioral activation and effort-related decision-making in motivated behaviors. Mesolimbic DA D2 receptors are co-localized with adenosine A2A receptors, and they interact in an antagonistic manner. Objectives A T-maze task was developed to assess dopaminergic involvement in preference between a reinforcer that involves vigorous voluntary activity (running wheel) and a reinforcer that requires minimal behavioral activation (sucrose pellets). Haloperidol (D2 antagonist) was administered to adenosine A2A receptor knockout (A2AKO) and wild-type (WT) littermate controls to assess the involvement of these two receptors in the selection of running wheel activity versus sucrose consumption. Results Under control conditions, mice spent more time running and less time eating. In WT mice, haloperidol reduced time running but actually increased time-consuming sucrose. However, A2AKO mice did not show the haloperidol-induced shift from running wheel activity to sucrose intake. Prefeeding reduced sucrose consumption in the T-maze in both strains, indicating that this paradigm is sensitive to motivational devaluation. Haloperidol increased c-Fos immunoreactivity in anterior cingulate cortex (ACg) and nucleus accumbens (Acb) core of WT but not KO mice. Conclusions These results indicate that after DA antagonism, the preference for vigorous physical activity is reduced, while palatable food selection increases. Adenosine A2A receptor deletion provides resistance to these effects of D2 receptor antagonism. These two receptors in Acb core and ACg seem to be involved in the regulation of the intrinsic reinforcing characteristics of voluntary exercise but not in the regulation of the primary reinforcing characteristics of palatable sedentary reinforcers