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The performance of rats on the conditioned blocking test (CB) of learned inattention was measured in a two-way shuttle avoidance task after sham and dopamine (DA) - depleting lesions of the frontal cortex, the limbic septum, and the ventral tegmental area (VTA - A10). Methods: Animals were trained on two sessions with tone and / or light as conditioned stimuli. One group was trained with both stimuli on both sessions. A second group was trained on the first session with one stimulus and on the second with both stimuli. The blocking of conditioning to the added stimulus (b) was tested by presenting the stimuli (a and b) separately and measuring the blocking ration (avoidance to b/a + b) and response latencies. Results: 1/ No deficits were recorded on tests of sensory and motor ability; 2/ The VTA group alone showed a hyperlocomotor response to apomorphine treatment, - and did not acquire the avoidance response (i.e. did not learn the active avoidance task); 3/ The appearance of blocking in the septally lesioned group was delayed until the end of the 20-trial test session - then it was exaggerated; 4/ Blocking was mildly attenuated in the frontally lesioned group. 5/ Dopamine (DA) levels were depleted by about 80% and noradrenaline (NA) levels by, respectively, 20% and 50% in the frontal and septal regions. Figure 2 illustrates a) the CB impairment in the frontal group relative to sham controls, and b) the late development of "supr-blocking" in septally-damage animals. Figure 3 illustrates the results of the HPLC analysis for NA, DA and DOPAC in frontal cortex, septum, N. accumbens and striatum after 6-OHDA lesions (& vehicle treatment) in the frontal, septal, and VTA areas. Conclusions: The results show that the levels of DA activity, or rather the balance between the activity of DA and NA in frontal and limbic regions can contribute to efficient associative conditioning and / or the normal ability of rats not to attend to a redundant stimulus.

Celiac disease (CD) is a chronic inflammatory enteropathy caused by gluten (protein from wheat, rye and, barley) in genetically predisposed individuals carrying the HLA-DQ2/HLA-DQ8 genotype. This pathology has a multifactorial etiology in which HLA genes, the microbiome, gluten and, other environmental factors are involved in the development of the disease. Its pathogenesis involves both innate and adaptive immunity as well as upregulation of IL-15. The objective of this review is to examine the results of current studies on genetic and environmental variables to better understand the pathogenesis of this enteropathy. The complex etiology of celiac disease makes our understanding of the pathogenesis of the disease incomplete, and a better knowledge of the many genetic and environmental components would help us better understand the pathophysiology of celiac disease., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Alcohol abuse is a widespread cause of aggressive and impulsive behaviors that impact the users as well as their entourage. However, only a few medications are effective. Recently, cannabidiol has been reported to improve mood disorders and recovery from substance abuse, yet the psychopharmacologic effects of cannabidiol in ethanol-induced drug reward and aggressivity remain unexplored. In the present study, we investigated the effects of cannabidiol on ethanol-induced place preference and aggressivity in individually and group-housed male rats using the conditioned place preference test, and intruder evoc aggression test, respectively. The obtained results showed that ethanol significantly increased locomotor activity, induced conditioned place preference in all animals, and, specifically, increased aggressivity in individually housed rats. These behavioural impairments induced by ethanol were associated with decreased glucocorticoid and mineralocorticoid receptors transcription in the prefrontal cortex. Notwithstanding, cannabidiol at a dose of 10 mg/kg significantly inhibited Et-OH-induced place preference in group-housed, but not in individually housed rats, and markedly inhibited the aggressive behaviour. These findings suggest that ethanol-induced behavioural impairments are dependent on the housing condition that may affect corticosterone receptors expression and subsequently the animal responsivity to cannabidiol treatment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: In common with other animal models of psychopathology, the forced-swimming test (FST) suffers from the fact that it involves normal animals. Moreover, powerful antidepressant drugs such as the selective serotonin reuptake inhibitors have been found to give false negatives in this behavioral test., Methods: To circumvent these theoretical and practical difficulties, we studied the interindividual variability of the behavioral reactivity of rats in the FST. The effects of fluoxetine treatment or of a stressful experience (repeated testing in the FST) were analyzed on various behavioral responses., Results: The following observations were made in replicated experiments: 1) a dimensional behavioral response from passivity to high reactivity in the FST; 2) an antidepressant-like effect of fluoxetine only in a subgroup of animals categorized as low responders on the dimension of passivity-reactivity; and 3) a switch toward passive responses following a past experience of stress, which was corrected by fluoxetine treatment., Conclusions: It is concluded that a dimensional approach could improve the screening of antidepressant drugs and could aid the development of new ones by identifying the biobehavioral characteristics of responder and nonresponder subjects.

The influence of the cerebral neocortex on the immunological status was studied in groups of C3H/He mice after lesioning the right or left fronto-parietal cortex. In left lesioned mice, mitogenesis induced either by phytohemagglutinin (PHA) or concanavalin A (Con A) was depressed by about 50% compared to controls. On the contrary, in animals with right lesions, T cell mitogenesis was enhanced by about 140% as compared to controls and by 220-300% as compared to that observed in left lesioned animals. Mitogenesis of B cells induced by lipopolysaccharide was modified by cortical lesions in exactly the same way as that of T cell proliferation although not reaching statistical significance. These results confirm the lateralization in the cortical modulation of the immune system.

Bovine serum albumin haloperidol (BSA-Hal) is a macromolecular complex with 14 molecules of haloperidol immobilized on the BSA protein backbone. This compound produces a selective, long lasting and reversible blockade of dopamine receptor activity. Its action was demonstrated by the ability to trigger a high rate of ipsilateral amphetamine-induced rotation up to 6 days after a single unilateral injection of the conjugate into the striatum. In the present study, the effect of the blockade of dopamine transmission in the nucleus accumbens (n.Acc) on spontaneous and learned behaviors was tested. The results indicate that the specific and long lasting blockade of dopamine receptors by bilateral injection of BSA-Hal in the n.Acc (1.6 micrograms/2 microliters) induced deficits in spontaneous alternation in a Y-maze on the 2nd and 5th days after the injection but not on the 11th day of the experiment, impaired acquisition but not retention in a radial 8-arm maze, increased latency to escape during learning in the place navigation task. These findings confirm the involvement of the n.Acc system in processes that have been generally attributed to the limbic system.