https://www.um.edu.mt/library/oar/handle/123456789/401 2026-10-15T19:05:51Z https://www.um.edu.mt/library/oar/handle/123456789/150004 Title: Alcohol and cannabinoid binges and daily exposure to nicotine in adolescent/young adult rats induce sex-dependent long-term appetitive instrumental learning impairment Authors: Abela, Norbert; Haywood, Katie; Di Giovanni, Giuseppe Abstract: Adolescence is a critical developmental period, concerning anatomical, neurochemical and behavioral changes. Moreover, adolescents are more sensitive to the long-term deleterious effects of drug abuse. Binge-like consumption of alcohol and marijuana, along with tobacco smoking, is a dangerous pattern often observed in adolescents during weekends. Nevertheless, the long-term effect of their adolescent co-exposure has not been yet experimentally investigated. Long-Evans adolescent male (n = 20) and female (n = 20) rats from postnatal day 30 (P30) until P60 were daily treated with nicotine (0.3 mg/kg, i.p.), and, on two consecutive ‘binging days’ per week (for a total of eight times), received an intragastric ethanol solution (3 g/kg) and an intraperitoneal (i.p.) dose of cannabinoid 1/2 receptor agonist WIN55,212-2 (1.2 mg/kg). These rats were tested after treatment discontinuation at > P90 for associative food-rewarded operant learning in the two-lever conditioning chambers for six consecutive days on a fixed ratio 1 (FR1) schedule followed by another six days of daily FR2 schedule testing, after 42 days rest. We found the main effects of sex x treatment interactions in FR1 but not in FR2 experiments. Treated females show attenuated operant responses for food pellets during all FR1 and the FR2 schedule, whilst the treated males show an impairment in FR2 but not in the FR1 schedule. Moreover, the treated females’ percentage of learners was significantly lower than female controls in FR1 while treated males were lower than controls in FR2. Our findings suggest that intermittent adolescent abuse of common drugs, such as alcohol and marijuana, and chronic tobacco exposure can cause significant long-term effects on motivation for natural reinforcers later in adulthood in both sexes. Females appear to be sensitive earlier to the deleterious effects of adolescent polydrug abuse, with both sexes having an increased likelihood of developing lifelong brain alterations. 2023-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/149988 Title: A quantitative and T‐pattern analysis of anxiety‐like behavior in male GAERS, NEC, and Wistar rats bred under the same conditions, against a commercially available Wistar control group in the hole board and elevated plus maze tests Authors: Casarrubea, Maurizio; Radic, Manuela; Morais, Tatiana P.; Mifsud, Erika; Cuboni, Eleonora; Aiello, Stefania; Crescimanno, Giuseppe; Crunelli, Vincenzo; Di Giovanni, Giuseppe Abstract: Aim: The Genetic Absence Epilepsy Rats from Strasbourg (GAERS) are an inbred polygenic model of childhood absence epilepsy (CAE), which, as their non-epileptic control (NEC) rats, are derived from Wistar rats. While the validity of GAERS in reproducing absence seizures is well established, its use as a model for CAE psychiatric comorbidities has been subject to conflicting findings. Differences in colonies, experimental procedures, and the use of diverse controls from different breeders may account for these disparities. Therefore, in this study, we compared GAERS, NEC, and Wistar bred in the same animal facility with commercially available Wistar (Cm Wistar) as a third control.; Methods: We performed hole board (HB) and elevated plus maze (EPM) tests that were analyzed with standard quantitative and T-pattern analysis in male, age-matched Cm Wistar and GAERS, NEC, and Wistar, bred under the same conditions, to rule out the influence of different housing factors and provide extra information on the structure of anxiety-like. behavior of GAERS rats.; Results: Quantitative analysis showed that GAERS and NEC had similar low anxiety-like behavior when compared to Cm Wistar but not to Wistar rats, although a higher hole-focused exploration was revealed in NEC. T-pattern analysis showed that GAERS, NEC, and Wistar had a similar anxiety status, whereas GAERS and NEC exhibited major differences with Cm Wistar but not Wistar rats. EPM results indicated that GAERS and NEC also have similar low anxiety compared to Cm Wistar and/or Wistar rats. Nevertheless, the analysis of the T-pattern containing open-arm entry showed GAERS and Wistar to be less anxious than NEC and Cm Wistar rats.; Conclusion: To summarize, comorbid anxiety may not be present in male GAERS rats. This study also highlighted the importance of including a control Wistar group bred under the same conditions when evaluating their behavior, as using Wistar rats from commercial breeders can lead to misleading results. 2024-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/149987 Title: Cognitive comorbidities of experimental absence seizures are independent of anxiety Authors: Neuparth-Sottomayor, Mariana; Pina, Carolina C.; Morais, Tatiana P.; Farinha-Ferreira, Miguel; Abreu, Daniela Sofia; Solano, Filipa; Mouro, Francisco; Good, Mark; Sebastião, Ana Maria; Di Giovanni, Giuseppe; Crunelli, Vincenzo; Vaz, Sandra Henriques Abstract: Typical absence seizures (ASs) are brief periods of lack of consciousness, associated with 2.5–4 Hz spike-wave discharges (SWDs) in the EEG, which are highly prevalent in children and teenagers. The majority of probands in these young epileptic cohorts show neuropsychological comorbidities, including cognitive, memory and mood impairments, even after the seizures are pharmacologically controlled. Similar cognition and memory deficits have been reported in different, but not all, genetic animal models of ASs. However, since these impairments are subtle and highly task-specific their presence may be confounded by an anxiety-like phenotype and no study has tested anxiety and memory in the same animals. Moreover, the majority of studies used non-epileptic inbred animals as the only control strain and this may have contributed to a misinterpretation of these behavioural results. To overcome these issues, here we used a battery of behavioural tests to compare anxiety and memory in the same animals from the well-established inbred model of Genetic Absence Epilepsy Rats from Strasbourg (GAERS), their inbred strain of Non-Epileptic Control (NEC) strain (that lack ASs) and normal outbred Wistar rats. We found that GAERS do not exhibit increased anxiety-like behavior and neophobia compared to both NEC and Wistar rats. In contrast, GAERS show decreased spontaneous alternation, spatial working memory and cross-modal object recognition compared to both NEC and Wistar rats. Furthermore, GAERS preferentially used egocentric strategies to perform spatial memory tasks. In summary, these results provide solid evidence of memory deficits in GAERS rats that do not depend on an anxiety or neophobic phenotype. Moreover, the presence of differences between NEC and Wistar rats stresses the need of using both outbred and inbred control rats in behavioural studies involving genetic models of ASs. 2023-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/149981 Title: Impressions of China – restoring my faith in humanity Abstract: Following his recent travels in Yinchuan, China, Chev. Prof. Renald Blundell has put pen to paper to share his experience. Blundell visited Yinchuan to deliver a lecture on Moringa oleifera’s bioactive compounds at the 9th International Symposium on Phytochemicals in Medicine and Food. But what came out of this experience would have a lasting impact on both his audience and himself. 2025-09-01T00:00:00Z