The term 'learned helplessness' refers to a constellation of behavioral changes that follow exposure to stressors that are not controllable by means of behavioral responses, but that fail to occur if the stressor is controllable. This paper discusses the nature of learned helplessness, as well as the role of the dorsal raphe nucleus, serotonin, and corticotropin-releasing hormone in mediating t...

Stress activates several neural pathways. The main stress response systems are the locus coeruleus, sympathetic-adrenal medullary system, and the hypothalamic–pituitary–adrenal (HPA) axis (Zhang et al., 2005). Stressors stimulate the paraventricular nuclei of the hypothalamus, where corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) are synthesized. CRH is a central component ...

Habitat heterogeneity has been linked to species diversity and abundance, but can also generate intraspecific behavioral variation that has functional consequences for how animals respond to environmental stressors. Previously, we found that bicolor damselfish Stegastes partitus inhabiting the fringing coral reefs of Curaçao exhibited intraspecific variation in agonistic behaviors in spatial pa...

Adverse early-life experiences, such as poor maternal care, program an abnormal stress response that may involve an altered balance between excitatory and inhibitory signals. Here, we explored how early-life stress (ELS) affects excitatory and inhibitory transmission in corticotrophin-releasing factor (CRF)-expressing dorsal-medial (mpd) neurons of the neonatal mouse hypothalamus. We report tha...

Titanium nitride (TiN) thin films deposited by high-power pulsed magnetron sputtering usually have a high compressive residual stress, which is not conducive for the adherence of TiN films. This study investigated potential Ti2AlN releasing stress HPPMS-deposited and evaluated strength hardness TiN/Ti2AlN multilayers introducing MAX phase to form multilayers. The results showed that smooth with...

Spontaneous histamine release from isolarted Mastcells was found to be independent of cal­cium in the concentration range up to 1 m. mole/lit. Phosphatidyl serine do not change the effect of calcium on spontaneous release. The activation of anaphyla.ctic histamine release by calcium is potentiated by phosphatidyl serine but the laitter can't do so w1th strontium.  Mastcells, pretreated with AT...

BACKGROUND Dysregulation of the hypothalamic-pituitary-adrenal (HPA)-axis is thought to underlie stress-related psychiatric disorders such as posttraumatic stress disorder (PTSD). Some studies have reported HPA-axis dysregulation in trauma-exposed (TE) adults in the absence of psychiatric morbidity. In this dissertation we set out to unravel part of the mechanism that underlies the complex rela...

Responding to stressful events requires numerous adaptive actions involving integrated changes in the central nervous and neuroendocrine systems. Numerous studies have implicated dysregulation of stress-response mechanisms in the etiology of stress-induced psychopathophysiologies. The urocortin neuropeptides are members of the corticotropin-releasing factor family and are associated with the ce...

Stress is among the strongest signals promoting neuroplasticity: Stress signals, indicating real or perceived danger, lead to alterations of neuronal function and often structure, designed to adapt to the changed conditions and promote survival. Corticotropin releasing factor (CRF) is expressed and released in several types of neuronal populations that are involved in cognition, emotion and the...

Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as...