Ethanol stimulates corticotropic releasing hormone (CRH) release from rat hypothalamic explants; role of acetaldehyde

Ethanol is able to activate the hypothalamic-pituitary-adrenal (HPA) axis, and to modify its response to other stressors, releasing adrenocorticotropic hormone (ACTH), and glucocorticoid release, (Lee et al 1999, 2000). In the brain ethanol is diverted by catalase activity into acetaldehyde, which is reported to mediate some of its behavioural and neurochemical effects. (Peana et al 2008, Melis et al 2007) Thus, to clarifìy the mechanisms underlying ethanol activity on the HPA axis we investigated :1) ethanol effect on CRH release from incubated hypothalamic explants; 2) the role of acetaldehyde (ACD), in mediating ethanol activity. To this aim, rat hypothalamic explants were incubated with…

Manipulations of glucocorticoid induced stress response may differently affect the acquisition of a reward-facilitated spatial-visual learning task.

The neurosteroids sulfate PREGS and DHEAS exert a facilitative role in learning performance in male rats.

Manipulations of glucocorticoids induced stress response may differently affect the acquisition of a reward-facilitated spatially/visual learning task.

Valutazione dell'attività dell'asse ipotalamo-ipofisi-surrene, in seguito all'esposizione in utero a stress acuto e cronico nella progenie di ratto adulta.

Single intense prenatal stress reduce behavioural suppression in an operant conflict paradigm in the adult progeny. Influence of Metyrapone administration

Stressors presented during late prenatal period can have long-term effects on offspring behaviour (1). Indeed we showed that in the rat progeny a single immobilization procedure at gestational day 16 enhances spatial learning in a non-aversive, rewarded-facilitated learning task, the Can Test, and decreases anxiety-like behaviour in the elevated plus maze (2). In this study, we wanted to investigate: (i) the effects of a single prenatal immobilization-stress on the operant conflict task (OCT), an anxiety-related procedure, in which positively reinforced responses are suppressed by contingent punishment (3); (ii) the expression of mineralcorticoid and glucocorticoid receptors (MRs, GRs) in t…

Perinatal Treatment with 5-metoxytriptamine affects cognition and behavioural reactivity in the juvenile male rat progeny; influence of maternal separation

Effects of prenatal acute stress on the behavioural reactivity in handled and non-handled rat progeny

The effects of prenatal stress are dependent on the intensity and duration of the stress treatment: chronic, uncontrollable stress causes an impairment in the normal adaptive responses to physical and physiological stimuli whereas acute and mild stress facilitates the morphological development of fetal brain neurons. The presents study was designed to investigate whether a single stress exposure during pregnancy may exert a facilitatory effect on the behaviour of the juvenile progeny. The effects of a postnatal handling procedure have been also investigated. One-month prenatally stressed rats (PSR) whose dams had been restrained for 120 minutes at the 16th day of gestation, showed an increa…

Repeated and single prenatal stress differently affect stress reactivity and learning performance in adolescent male rats

The neurosteroids sulphate PREGS and DHEAS exert a facilitative role on learning performance in adult male rats

Pregnenolone sulphate faciltates object recognition and reduces depressive-like behaviour in male adult rats

The neurosteroids DHEAS and PREGS may affect learning performance by altering affective state

Neurosteroid PREGS differently affects learning and memory performance by altering emotionality in a gender-related manner

Effects of Prenatal Treatment with 5-Metoxytryptamine on Learning Performance of Juvenile Male Rat Progeny. Influence of Maternal Separation

Effects with prenatal treatment with 5-metoxytriptamine on learning performance of juvenile male rat progeny. Influence of maternal separation

Effects of a single intense prenatal stress on emotionality and learning performance in adolescent male rat progeny.Influence of a daily short-term maternal separation.

Neurosteroid PREGS differently affects learning and memory performance by altering emotionality in a gender-related manner. 4th International Meeting Steroids and Nervous System, Torino, Italy. Febbrary 17-21 (2007)

Pregnenolone sulphate (PREGS) affects spatial learning and memory in two different cognitive tasks in adult rats. Influence of the emotional state.

Pregnenolone sulphate (PREGS) is one of the most potent memory-enhancing neurosteroids in rodent learning studies, also involved in the modulation of the emotional state (Valleè et al 2001). Neurosteroids exert an important role as modulators of the neuronal activity by interacting with different receptors or ion channels (Urani et al 1998). Indeed PREGS acts as negative modulator of GABAA- and as positive modulator of NMDA -receptors. Altered levels of PREGS have also been reported during aging and in human neurodegenerative pathologies like Alzheimer’s disease. The aim of this study was to investigate, in adult male rats, the effects of a single injection of PREGS (10 mg/kg s.c.) on: i) o…

Ethanol releases corticotropic releasing hormone (CRH) from rat hypothalamic explants; role of acetaldehyde

Ethanol activates hypothalamic-pituitary-adrenal (HPA) axis, resulting in adrenocorticotropic hormone (ACTH) glucocorticoid release, and a modification of the response of this axis to other stressors (Lee et al 1999, 2000). To determine the mechanisms responsible for these effects we investigated : 1) whether ethanol was able to release CRH from incubated hypothalamic explants; 2) whether acetaldehyde (ACD), its first metabolite formed in the brain by catalase activity, might play a role in ethanol effects. To this aim, rat hypothalamic explants were incubated with: 1) medium containing ethanol at 150 mg %; 2) different concentrations of ACD (4.4, 13.2, 44, 132 x 10-3 mg%); 3) ethanol plus …

Effect of Acetaldehyde on CRF release form incubated hypothalamic explants

In the past, Acetaldehyde (ACD), the main metabolite of ethanol (ETOH), was mainly studied for its toxic and adverse effects (1). However, recently, ACD was reported to determine behavioural and neurochemical effects, following ETOH assumption in rodents (2, 3). Indeed, ACD enhances dopamine levels in nucleus accumbens, stimulates beta-endorphin release from hypothalamic cells, mediating alcohol reinforcing effects (4). Since little is known about the effects of ACD on other central neuropeptides, in this research we aimed to investigate ACD influence on hypothalamic corticotropin-releasing factor (CRF) release. In order to ascertain this hypothesis, different doses of ACD (1, 10, 3x10 micr…