0000000000388247
AUTHOR
Bruno Ribeiro Do Couto
Effect of adolescent exposure to WIN 55212-2 on the acquisition and reinstatement of MDMA-induced conditioned place preference.
The present study employs a conditioned place preference procedure (CPP) to examine the effects of exposure to the cannabinoid agonist WIN 55212-2 (WIN) (0.1 and 0.5mg/kg) during adolescence on the reinforcing properties of +/-3,4-methylenedioxymetamphetamine hydrochloride (MDMA) (1.25 and 2.5mg/kg) in mice. On postnatal day (PD) 27, animals received a daily injection of the assigned treatment on 5 consecutive days, and three days later the place conditioning procedure was initiated (PD 35). The results suggest that pre-exposure to cannabinoids strengthens the properties of MDMA and favors reinstatement of the craving for the drug, which endorses the gateway hypothesis.
Effects of an incremental maximal endurance exercise stress-induced cortisol on cognitive performance
Exercise; Cognitive functions; Cortisol Ejercicio físico; Funciones cognitivas; Cortisol Exercici físic; Funcions cognitives; Cortisol Objectives: It can be hypothesized that cognitive performance decreases after fatigue protocol when it coincides with the maximum peak of cortisol. The first aim of this study was to elucidate the effects of a single bout of high intensity exercise on behavioural (i.e., attention and memory) and physiological (i.e., salivary cortisol) responses. The second objective was to evaluate the effect of the performance of the cognitive tasks on cortisol levels. Methods: Thirty-four physically active men (at least 5 days/week of physical activity practice) 38.11 (1.5…
The Mediator Role of Feelings of Guilt in the Process of Burnout and Psychosomatic Disorders: A Cross-Cultural Study
Burnout was recently declared by WHO as an “occupational phenomenon” in the International Classification of Diseases 11th revision (ICD-11), recognizing burnout as a serious health issue. Earlier studies have shown that feelings of guilt appear to be involved in the burnout process. However, the exact nature of the relationships among burnout, guilt and psychosomatic disorders remains unclear. The purpose of this study was to investigate the mediator role of feelings of guilt in the relationship between burnout and psychosomatic disorders, and perform a cross-cultural validation of the multi-dimensional model by Gil-Monte in two samples of teachers (Portuguese vs. Spanish). The study sample…
Influence of a Cognitive Behavioural Training Program on Health: A Study among Primary Teachers // Influencia de un programa de entrenamiento cognitivo conductual sobre la salud: Un estudio con profesorado de Educación Primaria
This longitudinal study was carried out to assess the efficacy of a cognitive behavioural training program that was designed to modify the cognitive and emotional processes related to work stress in a sample of teachers. The training group consisted of 21 teachers, and the non training group comprised of 16 teachers. The training program was divided into four on-site sessions, and the difference between time 1 and time 2 was 4 months. The training program significantly reduced psychosomatic disorders levels in the training group from Time 1 to Time 2, and it significantly increased cortisol levels from time 1 to time 2.
Memantine blocks sensitization to the rewarding effects of morphine
Knowledge regarding the specific brain changes and neural plasticity processes produced by repeated drug exposure may be used to advance the understanding of the neurobiology of addiction in order to design appropriate medications. In the present study, the influence of N-methyl-d-aspartate (NMDA) glutamatergic receptors on sensitization to the motor and rewarding effects of morphine was evaluated. The effects of pre-exposure to saline or 20 mg/kg morphine plus the NMDA receptor antagonist memantine (10 or 20 mg/kg) on motor activity and place conditioning induced by a low dose of morphine (2 mg/kg) were assessed. The dose of 2 mg/kg of morphine was ineffective in mice pre-exposed to saline…
Changes in histone acetylation in the prefrontal cortex of ethanol-exposed adolescent rats are associated with ethanol-induced place conditioning
Alcohol drinking during adolescence can induce long-lasting effects on the motivation to consume alcohol. Abnormal plasticity in reward-related processes might contribute to the vulnerability of adolescents to drug addiction. We have shown that binge-like ethanol treatment in adolescent rats induces alterations in the dopaminergic system and causes histone modifications in brain reward regions. Considering that histone acetylation regulates transcriptional activity and contributes to drug-induced alterations in gene expression and behavior, we addressed the hypothesis that ethanol is capable of inducing transcriptional changes by histone modifications in specific gene promoters in adolescen…
Rewarding effects and reinstatement of MDMA-induced CPP in adolescent mice.
Although the rewarding effects of 3,4-methylenedioxy-metamphetamine (MDMA) have been demonstrated in self-administration and conditioned place preference (CPP) procedures, its addictive potential (ie, the vulnerability to relapse, measured by its ability to induce reinstatement of an extinguished response), remains poorly understood. In this study, the effects of MDMA (5, 10, and 20 mg/kg) on the acquisition, extinction and reinstatement of CPP were evaluated in mice, using two different protocols during acquisition of CPP. In the first experiment, animals were trained using a two-session/day schedule (MDMA and saline for 4 consecutive days), whereas in the second experiment, they were trai…
Involvement of nitric oxide synthesis in sensitization to the rewarding effects of morphine
Abstract Knowledge about the specific brain changes and neural plasticity processes produced by repeated exposure to a drug is essential to progress in the field of neurobiology of addiction and the development of effective medication. In the present study, the influence of nitric oxide synthesis on sensitization to the rewarding effects of morphine has been evaluated. The effects of pre-treatment of mice with saline or 20 mg/kg of morphine plus the nitric oxide synthase inhibitor 7-nitroindazole (7NI) (12.5 or 25 mg/kg) on the place conditioning induced by a low dose of morphine (2 mg/kg) were assessed. The dose of 2 mg/kg of morphine was ineffective in animals pre-treated with saline but …
Adolescent pre-exposure to ethanol and 3,4-methylenedioxymethylamphetamine (MDMA) increases conditioned rewarding effects of MDMA and drug-induced reinstatement
Many adolescents often take ethanol (EtOH) in combination with 3,4-methylenedioxymethylamphetamine (MDMA). In the present work, we used a mouse model to study the effect of repeated pre-exposure during adolescence to EtOH (2 g/kg), MDMA (10 or 20 mg/kg) or EtOH + MDMA on the rewarding and reinstating effects of MDMA in the conditioned place preference (CPP) paradigm. Pre-exposure to EtOH, MDMA or both increased the rewarding effects of a low dose of MDMA (1.25 mg/kg). These pre-treatments did not affect the acquisition of the CPP induced by 5 mg/kg of MDMA. However, the CPP was more persistent in mice pre-exposed to both doses of MDMA or to EtOH + MDMA20. After extinction of the CPP induced…