No description available.

Maternal stress during the perinatal period has been linked to attention and behavioral problems and increased adrenocortical activity in children. Underlying this relationship is thought to be exposure to excessive glucocorticoids during development. The aim of this set of studies was to determine the effects of chronic maternal stress (CMS) during the perinatal period on behaviour and endocrine function in male and female guinea pig offspring at the juvenile and adult life stage. Environmental enrichment was investigated as a potential therapeutic tool to reverse changes induced by CMS. Pregnant guinea pigs were exposed to a sequence of stressors every other day over the second half of gestation until weaning on postnatal day 25. Offspring were tested for ambulatory activity, attention, cognitive function, sex-steroid levels and adrenocortical function. One cohort of animals were housed in an enriched environment, the remaining offspring were housed in standard conditions. A separate cohort was administered amphetamine (1 mg/kg) prior to behavioural testing to determine influence of CMS on dopaminergic function. Juvenile male and female offspring of mothers exposed to stress exhibited increased basal and decreased stress-induced salivary cortisol, and male offspring displayed reduced activity and a phase shift in their circadian rhythm of activity. Adult male offspring of CMS mothers exhibited increased activity in a novel environment and decreased activity in a familiar environment. Female adult offspring of CMS mothers exhibited reduced attention and increased activity in a novel environment. Enrichment acted independently of CMS, increasing plasma testosterone and attention in adult male offspring and reducing the adrenocortical response to stress and decreasing attention and activity in female offspring. Amphetamine decreased activity in a novel environment and increased activity in a familiar environment in both sexes, regardless of age or maternal treatment. Amphetamine improved attention in juvenile and adult males. The current studies demonstrated a strong effect of CMS on behaviour in juvenile and adult offspring. Enrichment was not effective for attenuating the effects of CMS. These studies clearly demonstrate behavioural changes as a result of CMS emerge over the lifetime of the offspring and have begun to uncover the underlying mechanisms of programming.

Maternal stress during the perinatal period has been linked to attention and behavioral problems and increased adrenocortical activity in children. Underlying this relationship is thought to be exposure to excessive glucocorticoids during development. The aim of this set of studies was to determine the effects of chronic maternal stress (CMS) during the perinatal period on behaviour and endocrine function in male and female guinea pig offspring at the juvenile and adult life stage. Environmental enrichment was investigated as a potential therapeutic tool to reverse changes induced by CMS. Pregnant guinea pigs were exposed to a sequence of stressors every other day over the second half of gestation until weaning on postnatal day 25. Offspring were tested for ambulatory activity, attention, cognitive function, sex-steroid levels and adrenocortical function. One cohort of animals were housed in an enriched environment, the remaining offspring were housed in standard conditions. A separate cohort was administered amphetamine (1 mg/kg) prior to behavioural testing to determine influence of CMS on dopaminergic function. Juvenile male and female offspring of mothers exposed to stress exhibited increased basal and decreased stress-induced salivary cortisol, and male offspring displayed reduced activity and a phase shift in their circadian rhythm of activity. Adult male offspring of CMS mothers exhibited increased activity in a novel environment and decreased activity in a familiar environment. Female adult offspring of CMS mothers exhibited reduced attention and increased activity in a novel environment. Enrichment acted independently of CMS, increasing plasma testosterone and attention in adult male offspring and reducing the adrenocortical response to stress and decreasing attention and activity in female offspring. Amphetamine decreased activity in a novel environment and increased activity in a familiar environment in both sexes, regardless of age or maternal treatment. Amphetamine improved attention in juvenile and adult males. The current studies demonstrated a strong effect of CMS on behaviour in juvenile and adult offspring. Enrichment was not effective for attenuating the effects of CMS. These studies clearly demonstrate behavioural changes as a result of CMS emerge over the lifetime of the offspring and have begun to uncover the underlying mechanisms of programming.

No description available.

No description available.

Stress is a widespread phenomenon in the western society of these days. It is a risky factor for health and well-being of the majority of people. Based on these facts, it is the main subject for the field of "stress physiology" research, which aims to study processes occurring during stress response and tries to elucidate mechanisms leading to stress-induced health impairment. The first aim of this thesis was to describe effects of psycho-social stress on organism. The second aim was to find out if can stress applied in juvenile age affect the stress response in adulthood. If so, how is the role of glucocorticoid-metabolism enzyme 11β-HSD1 in this influence? To answer these questions, two different animal models inducing stress response in the laboratory rat were used. The first one is the model of mild social stress based on the resident-intruder paradigm. Our results show efficancy of this model. Fisher 344 male rats treated under this model for seven consecutive days show highly elevated plasma corticosterone concentrations and elevated expression of the glucocorticoid receptor gene in the pituitary. Behavioral analysis demonstrates a decreased social behavioral profile of the intruders, suggesting submisive social position of these animals in the resident-intruder paradigm. The second model used is...