Antidepressant treatment differentially affects the phenotype of high and low stress reactive mice.

Modelling key endophenotypes can be a powerful approach to gain insight into mechanisms underlying the aetiology and pathophysiology of neuropsychiatric disorders. Based on evidence of stress hormone system dysregulations in depression, the Stress Reactivity (SR) mouse model has been generated by a selective breeding approach for extremes in HPA axis reactivity, resulting in high (HR), intermediate (IR) and low (LR) reactive mice. The characterisation of their phenotypic alterations has highlighted many similarities of HR and LR mice with the melancholic and atypical depression, respectively.

Dendritic morphology of hippocampal and amygdalar neurons in adolescent mice is resilient to genetic differences in stress reactivity.

Many studies have shown that chronic stress or corticosterone over-exposure in rodents leads to extensive dendritic remodeling, particularly of principal neurons in the CA3 hippocampal area and the basolateral amygdala. We here investigated to what extent genetic predisposition of mice to high versus low stress reactivity, achieved through selective breeding of CD-1 mice, is also associated with structural plasticity in Golgi-stained neurons. Earlier, it was shown that the highly stress reactive (HR) compared to the intermediate (IR) and low (LR) stress reactive mice line presents a phenotype, with respect to neuroendocrine parameters, sleep architecture, emotional behavior and cognition, that recapitulates some of the features observed in patients suffering from major depression.

Urocortin 2 modulates aspects of social behaviour in mice.

Urocortin 2 (UCN2), a member of the corticotropin-releasing hormone family, is involved in the regulation of stress-related behaviours in rodents. To determine its physiological function we generated mice lacking UCN2 by applying a classical knockout strategy. We examined hypothalamus-pituitary-adrenocortical axis activity, anxiety- and depression-related behaviours without finding significant differences between mutant and wild-type littermates.

Increased stress reactivity is associated with reduced hippocampal activity and neuronal integrity along with changes in energy metabolism.

Patients suffering from major depression have repeatedly been reported to have dysregulations in hypothalamus-pituitary-adrenal (HPA) axis activity along with deficits in cognitive processes related to hippocampal and prefrontal cortex (PFC) malfunction. Here, we utilized three mouse lines selectively bred for high (HR), intermediate, or low (LR) stress reactivity, determined by the corticosterone response to a psychological stressor, probing the behavioral and functional consequences of increased vs. decreased HPA axis reactivity on the hippocampus and PFC.

FK506 binding protein 5 shapes stress responsiveness: modulation of neuroendocrine reactivity and coping behavior.

Background: The Hsp90 cochaperone FK506 binding protein 5 (FKBP5) is an established regulator of the glucocorticoid receptor (GR), and numerous genetic studies have linked it to stress-related diseases such as major depression or posttraumatic stress disorder. However, translational studies including genetic animal models are lacking.

Methods: Mice deficient of FKBP5 were generated and analyzed in comparison with wildtype littermates.

Effects of prenatal dexamethasone treatment on physical growth, pituitary-adrenal hormones, and performance of motor, motivational, and cognitive tasks in juvenile and adolescent common marmoset monkeys.

Synthetic glucocorticoids such as dexamethasone (DEX) are commonly used to prevent respiratory distress syndrome in preterm infants, but there is emerging evidence of subsequent neurobehavioral abnormalities (e.g. problems with inattention/hyperactivity).

Effects of prenatal dexamethasone treatment on postnatal physical, endocrine, and social development in the common marmoset monkey.

The prophylactic treatment of diagnosed preterm delivery with synthetic glucocorticoids, such as dexamethasone (DEX), is commonplace. Long-term effects of such treatment are not well understood. In the present study, we exposed pregnant common marmosets (Callithrix jacchus), small-bodied monkeys that are therefore advantageous for long-term primate studies, to daily repeated DEX (5 mg/kg orally) either during early (d 42-48) or late (d 90-96) pregnancy (gestation period of 144 d).