Influence of imipramine on the duration of immobility in chronic forced-swim-stressed rats.

We studied the influence of imipramine on the duration of immobility in chronic forced-swim-stressed rats. Both single and chronic administration of imipramine potently shortened immobility in naive rats during forced-swim testing. However, chronic, 14-day forced-swim stress testing blocked the immobility-decreasing effect induced by a single administration of imipramine. When imipramine was administered for 14 days concurrently with forced-swim stress testing, immobility was shortened significantly. From the viewpoint of imipramine's effect, these findings suggest that chronic forced-swim stress testing in rats may be an effective animal model for depression.</p

Psychosocial Predictors of Metabolic Syndrome among Latino Groups in the Multi-Ethnic Study of Atherosclerosis (MESA).

ObjectiveWe sought to determine the contribution of psychological variables to risk for metabolic syndrome (MetS) among Latinos enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA), and to investigate whether social support moderates these associations, and whether inflammatory markers mediate the association between psychological variables and MetS.Research design and methodsCross-sectional analyses at study baseline were conducted with a national Latino cohort (n = 1,388) that included Mexican Americans, Dominican Americans, Puerto Rican Americans and Central/South Americans. Hierarchical logistic regression analyses were conducted to test the effects of psychosocial variables (chronic stress, depressive symptoms, and social support) on MetS. In addition, separate subgroup-specific models, controlling for nationality, age, gender, socioeconomic position, language spoken at home, exercise, smoking and drinking status, and testing for the effects of chronic stress, depressive symptoms and inflammation (IL-6, CRP, fibrinogen) in predicting risk for MetS were conducted.ResultsIn the overall sample, high chronic stress independently predicted risk for MetS, however this association was found to be significant only in Mexican Americans and Puerto Rican Americans. Social support did not moderate the associations between chronic stress and MetS for any group. Chronic stress was not associated with inflammatory markers in either the overall sample or in each group.ConclusionsOur results suggest a differential contribution of chronic stress to the prevalence of MetS by national groups

Effects of stress and relaxation on central pain modulation in chronic whiplash and fibromyalgia patients compared to healthy controls

Background: Compelling evidence has demonstrated that impaired central pain modulation contributes to persistent pain in patients with chronic whiplash associated disorders (WAD) and fibromyalgia (FM). However, there is limited research concerning the influence of stress and relaxation on central pain modulation in patients with chronic WAD and FM. Objectives: The present study aims to investigate the effects of acute cognitive stress and relaxation on central pain modulation in chronic WAD and FM patients compared to healthy individuals. Study Design: A randomized crossover design was employed. Setting: The present study took place at the University of Brussels, the University Hospital Brussels, and the University of Antwerp. Methods: Fifty-nine participants (16 chronic WAD patients, 21 FM, 22 pain-free controls) were enrolled and subjected to various pain measurements. Temporal summation (TS) of pain and conditioned pain modulation (CPM) were evaluated. Subsequently, participants were randomly allocated to either a group that received progressive relaxation therapy or a group that performed a battery of cognitive tests (= cognitive stressor). Afterwards, all pain measurements were repeated. One week later participant groups were switched. Results: A significant difference was found between the groups in the change in TS in response to relaxation (P = 0.008) and cognitive stress (P = 0.003). TS decreased in response to relaxation and cognitive stress in chronic WAD patients and controls. In contrast, TS increased after both interventions in FM patients. CPM efficacy decreased in all 3 groups in response to relaxation (P = 0.002) and cognitive stress (P = 0.001). Limitations: The obtained results only apply for a single session of muscle relaxation therapy and cognitive stress, whereby no conclusions can be made for effects on pain perception and modulation of chronic cognitive stress and long-term relaxation therapies. Conclusions: A single relaxation session as well as cognitive stress may have negative acute effects on pain modulation in patients with FM, while cognitive stress and relaxation did not worsen bottom-up sensitization in chronic WAD patients and healthy persons. However, endogenous pain inhibition, assessed using a CPM paradigm, worsened in chronic WAD and FM patients, as well as in healthy people following both interventions

Comparison of personality traits among patients with psoriasis, atopic dermatitis, and stress: a pilot study

Background: Psoriasis and atopic dermatitis are chronic skin diseases that greatly affect the quality of life. Both diseases can be triggered or exacerbated by stress. Objective: We aimed to differentiate personality traits between patients with chronic skin conditions and people treated for stress in a pilot study. Methods: Patients participating voluntarily in educational programs in Belgium and Switzerland were recruited to complete personality trait questionnaires, including the Temperament and Character Inventory (TCI) and the Tridimensional Personality Questionnaire (TPQ). A comparison was made with patients treated for work-related stress. Results: A total of 48 and 91 patients suffering from skin diseases and work-related stress, respectively, were included in the study. Based on the questionnaires, we found that dermatology patients were less persistent and impulsive than those with work-related stress. Dermatology patients also exhibited more rigidness and less focus on performance. Finally, patients with work-related stress seem more likely to change in response to health-promoting programs than patients with chronic dermatoses. Conclusion: Patients with chronic skin diseases may perceive and cope with stress differently in comparison to patients with work-related stress due to inherent personality traits. Therefore, stress coping mechanisms may differ among different diseases. More research is needed into the design of educational interventions and the impact of personality traits in disease-specific groups

The effect of chronic peripheral nesfatin-1 application on blood pressure in normal and chronic restraint stressed rats: Related with circulating level of blood pressure regulators

Nesfatin is a peptide secreted by peripheral tissues, central and peripheral nervous system. It is involved in the regulation of homeostasis. Although the effects of nesfatin-1 on nutrition have been studied widely in the literature, the mechanisms of nesfatin-1 action and also relations with other physiological parameters are still not clarified well. We aimed to investigate the effect of peripheral chronic nesfatin-1 application on blood pressure regulation in normal and in rats exposed to restraint immobilization stress. In our study, three month-old male Wistar rats were used. Rats were divided into 4 groups as Control, Stress, Control+Nesfatin-1, Nesfatin-1+Stress. Angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-1, endothelial nitric oxide synthase, aldosterone, cortisol, nesfatin-1 levels were determined in plasma samples by ELISA. Our results have shown that chronic peripheral nesfatin-1 administration increases blood pressure in normal and in rats exposed to chronic restraint stress. Effect of nesfatin-1 on circulating level of angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-1, endothelial nitric oxide synthase, aldosterone and cortisol has been identified. We can conclude that elevated high blood pressure after chronic peripheral nesfatin-1 administration in rats exposed to chronic restraint stress may be related to decreased plasma level of endothelial nitric oxide synthase concentration

Stress in wild and captive snakes : quantification, effects and the importance of management

As in other animals, distress and impaired welfare have a deleterious effect on the mental, physical and behavioral health of snakes in the wild and in captivity. Besides anthropogenic disturbance, the availability of food and shelter, the presence of predators, and environmental factors, such as seasonality and climatological changes, are important factors that affect the stress level and subsequent welfare in wild snake populations. In captive snakes, inappropriate management is the most prominent cause of chronic stress and impaired welfare. Chronic stress can be assumed by looking at the snake's behavior, but there is need for a standardized quantification method to pin-point more accurately (chronic) stress levels. The biomarker suitable in this framework is the level of corticosterone in plasma, feces and shed skin

Effect of Perceived Stress on Cytokine Production in Healthy College Students

Chronic psychological stress impairs antibody synthesis following influenza vaccination. Chronic stress also increases circulating levels of proinflammatory cytokines and glucocorticoids in elders and caregivers, which can impair antibody synthesis. The purpose of this study was to determine whether psychological stress increases ex vivo cytokine production or decreases glucocorticoid sensitivity (GCS) of peripheral blood leukocytes from healthy college students. A convenience sample of Reserve Officer Training Corps (ROTC) students completed the Perceived Stress Scale (PSS). Whole blood was incubated in the presence of influenza vaccine and dexamethasone to evaluate production of interleukin-6 (IL-6), interleukin-1-beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ). Multiple regression models controlling for age, gender, and grade point average revealed a negative relationship between PSS and GCS for vaccine-stimulated production of IL-1β, IL-6, and TNF-α. These data increase our understanding of the complex relationship between chronic stress and immune function

Impacts of chronic stress on urinary bladder function & recovery through modification of PACAP signaling

Stress can cause or contribute to bladder dysfunction though specific effects remain unclear. Individuals with interstitial cystitis (IC)/bladder pain syndrome (BPS) experience increased symptom severity with stress, including pain and increased urgency and frequency of voiding. Further research can identify stress-related changes to urinary mechanisms, such as changes in sensory neurotransmitters and subsequent receptor expression. These factors could then become targets for future therapies providing bladder dysfunction relief. Alterations in PACAP and TRPV channel expression have been shown in sensory pathways in response to disease. My research studied the effects of chronic stress on bladder function and the potential for PACAP(6-38), a PACAP antagonist, to recover normal function. Mice went through a repeated variate stress regime followed by bladder tube implant and cystometrogram recording. Bladder, dorsal root ganglia (DRG), and spinal cord tissues were collected and immunostained for the presence of TRPV1, TRPV4, and PACAP expression. Chronic stress decreased inter-contraction interval (ICI) and bladder capacity while increasing bladder pressures. Both control and stressed male and female mice showed improvement following a 30-minute intravesical infusion of PACAP(6-38), with ICI and bladder capacity measures having the most consistent improvement across groups. PACAP and TRPV1 expression was upregulated in the bladder afferent pathway. These findings suggest that chronic stress can contribute to bladder dysfunction, and it seems to be mediated in part by upregulation of PACAP and TRPV channel activity. With further research, these factors may be valid molecular targets for therapy. As chronic stress may present alone or in combination with other conditions (IC/BPS, injury, etc.), it is critical to understand stress-related changes in order to reduce or eliminate their impact

The Effect of Socio-economic Status and Related Stress on Physical Health

This review is designed to investigate how socioeconomic status, and the stress related to it, can impact physical health. Much of the research relating to this topic focuses on how low socioeconomic status effects health. However, it is very important to understand the different ways that all classes effect health outcomes. An important mediating factor in the relationship between socioeconomic status and health is chronic stress. The presence of chronic stress can produce serious negative health outcomes. High stress appears on all levels of the social hierarchy, but formulates for unique reasons within the different classes