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Journal Article 2016; 37(Suppl 1): 103-110 PubMed PMID: 28263537 Citation  Keywords:  Animals, Anxiety:physiopathology, Behavior, Animal:physiology, Corticosterone:blood, Depression:physiopathology, Disease Models, Animal, Male, Rats, Rats, Wistar, Stress, Psychological:blood,.   

OBJECTIVES: There are several models of depression. Chronic unpredictable mild stress (CMS) appears to have the greatest validity, although it is often being criticized for low reliability.

METHODS: Male Wistar/DV rats were used in this study to assess our modified 2-week model of CMS as a combination of psychosocial, physical and metabolic stressors and to compare the effect of acute administration of venlafaxine (VFX) and diazepam (DZP), either in stress or no stress conditions. The animals were exposed to one particular stressor each day. The time of day and duration of the stressor differed across the procedure to avoid animals to adapt to the stress stimulus. After cessation of stress, the animals underwent the following behavioral tests to assess motor activity, cognition, anxiety- and depression-like behavior: Open field test, Elevated plus maze, Forced swim test, Stress-iduced hyperthermia, Light/dark test and Y maze. To assess hypothalamic-pituitary-adrenal axis (HPA) reactivity in our CMS model, plasma corticosterone levels were measured 24 h after termination of stress.

RESULTS: Corticosterone levels were significantly increased compared to control values (p<0.05) in our experimental schedule of CMS. Our paradigm produced delayed anxiety-like behavior observed in Open field (decreased time spent in central zone 3 weeks after CMS, p<0.05), with anxiolytic effect of CMS shortly after its cessation. Stressed animals spent more time in the open arms of Elevated plus maze (p<0.05) and travelled longer distance in the light zone of the Light/dark box (p<0.01). CMS did not increase the behavioral despair analyzed in Forced swim test yet it disrupted the capacity of the Stress-induced hyperthermia test (CMS rats failed to react to the stress by increasing the core temperature).

CONCLUSIONS: Based on our results, we can conclude that our CMS protocol leads to increased corticosterone levels as a result of HPA axis hyperactivity and produces delayed onset of anxiogenic behavior. Moreover, CMS exerted a substantial effect on the behavioral outputs, interfering with drug testing.

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Journal Article 2014; 35(3): 213-217 PubMed PMID: 24977971 Citation  Keywords:  Adult, Aged, Child, Crime Victims:psychology, Female, Humans, Life Change Events, Male, Middle Aged, Oxytocin:blood, Stress, Psychological:blood, Suicide, Attempted:psychology, Violence:psychology, Young Adult,.   

OBJECTIVE: Some studies have reported an inverse relationship between childhood adversity and oxytocin levels. The purpose of this study was to assess the relationship between CSF and plasma oxytocin levels and lifetime trauma history in suicide attempters. We hypothesised lower CSF and plasma oxytocin levels in suicide attempters with high exposure to interpersonal violence and negative childhood emotional climate.

METHODS: 28 medication free suicide attempters participated in the study. CSF and plasma morning basal levels of oxytocin were assessed with specific radioimmunoassays. The Karolinska Interpersonal Violence Scale (KIVS) was used to elicit lifetime trauma history and revictimization status and the childhood emotional climate factor was derived from the socialization subscale of the Karolinska Scales of Personality.

RESULTS: Correlations between exposure to interpersonal violence as a child and as an adult and CSF and plasma oxytocin levels were not significant. Revictimized suicide attempters had significantly lower plasma oxytocin levels and more negative childhood emotional climate compared to non-revictimized suicide attempters.

CONCLUSIONS: Our results indicate a complex relationship between life time trauma and the oxytocin system....

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Journal Article 2007; 28(5): 585-590 PubMed PMID: 17984949 Citation  Keywords:  Adaptation, Psychological:physiology, Aggression:physiology, Animals, Corticosterone:blood, Dominance-Subordination, Hypothalamo-Hypophyseal System:physiology, Male, Mice, Mice, Inbred BALB C, Social Environment, Stress, Psychological:blood, Territorialit.   

OBJECTIVE: Social stressors modulate the hypothalamic-pituitary-adrenal axis in rodents. However, reports on the association between corticosterone level and behavioural responses to the stressor are ambivalent. This may depend on the experimental paradigm, species- and strain-differences, duration of exposure to the stressor, but also on using either the social state (dominant or subordinate) or the coping style (proactive or passive) of an animal to correlate the corticosterone level with.

DESIGN AND SETTING: We used male Balb-C mice in a resident-intruder paradigm. Adolescent intruders (aged five to eight weeks) were transferred into the cage of an adult resident (aged about four month) for five minutes. The interactions were video-taped for behavioural analysis. Ten minutes after the encounters, intruders were sacrificed and blood samples were collected.

RESULTS: Dominant intruders showed offensive behaviours (attack, chase, tail tracking) and won most of the fights, whereas subordinate intrudes showed mainly submissive behaviours (flight, freezing) and were further classified into active and passive subordinates. Active subordinates displayed significantly more flight-behaviour than passive subordinates. Dominant intruders showed significantly higher post-stress levels of corticosterone than subordinates, which did not differ from control mice, which experienced five minutes of novel-cage exposure. Comparing all three behavioural phenotypes we found the lowest corticosterone levels in active subordinates.

CONCLUSION: Social state significantly affects the HPA-axis response to acute social stressors....

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Journal Article 2005; 26(4): 347-350 PubMed PMID: 16136011 Citation  Keywords:  Adrenocorticotropic Hormone:blood, Adult, Follicle Stimulating Hormone:blood, Humans, Hydrocortisone:blood, Infertility, Male:blood, Leydig Cells:metabolism, Luteinizing Hormone:blood, Male, Sperm Count, Stress, Psychological:blood, Testosterone:biosynthe.   

INTRODUCTION: Emotional stress connected with work or, for example, depressive reaction to infertility, is one of frequent causes of decreased quality of semen. An objective examination of this factor is difficult because stress depends also on patient's emotionality. One of the ways to study this problem is evaluating the relation between ACTH level and selected semen parameters.

MATERIAL AND METHODS: The study was based on results of the examination of 83 men from couples treated for infertility in the Gynecology and Infertility Clinic of the Jagiellonian University in Krakow. Determination of ACTH, FSH, LH, cortisol, testosterone and androstendion was performed using ELISA.

RESULTS: Lower average values of semen volume, sperm cells concentration and A sperm cell mobility and higher value of D sperm cells mobility were identified in the group of men from couples treated for infertility with ACTH level >30 pg/ml in comparison to the WHO standards and the control group with ACTH <30 pg/ml. Higher ACTH and cortisol levels were detected in the group of men with the sperm count <10 mln/mL in comparison to the control group with the sperm count >20 mln/mL. Low and statistically insignificant correlation was observed between androstendion and testosterone levels, what might suggest the reduction of testosterone synthesis in this group.

CONCLUSIONS: Our results might indicate that the rise of ACTH and cortisol inhibit the conversion of adrostendion into testosterone in Leydig-cells resulting in the rise of androstendion, drop of testosterone production and lower average values of semen volume, sperm cells concentration and A sperm cell mobility and higher value of D sperm cells mobility....

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Journal Article 2005; 26(4): 351-354 PubMed PMID: 16136010 Citation  Keywords:  Acute Disease, Adult, Anxiety:blood, Humans, Hydrocortisone:blood, Male, Personality:physiology, Social Behavior, Stress, Psychological:blood,.   

OBJECTIVES: Traditionally, it has been hypothesized that highly anxious/emotionally reactive subjects may have exaggerated social stress response. We examined the relationship between self-reported anxiety, emotional reactivity, and social stress response.

METHODS: We investigated the relationship between personality scales of trait-state anxiety, subjective autonomic reactivity, and salivary cortisol levels before and after social stress exposure (Trier Social Stress Test) in 20 men.

RESULTS: Significant positive correlations between anxiety, subjective autonomic reactivity, and basal cortisol levels were observed, while neither anxiety nor subjective autonomic reactivity was correlated with social stress-induced cortisol elevation.

CONCLUSIONS: The present results indicate (i) subjects with higher degrees of trait anxiety/subjective autonomic reactivity have higher basal cortisol levels, and (ii) in contrast to the traditional view, anxious personality is not strongly associated with exaggerated cortisol response to social stress....

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Journal Article 2005; 26(4): 355-360 PubMed PMID: 16136009 Citation  Keywords:  Adaptation, Psychological, Adult, Aggression:physiology, Female, Hostility, Humans, Male, Middle Aged, Personality:physiology, Reference Values, Stress, Psychological:blood, Testosterone:blood,.   

OBJECTIVES: Many studies assessing the role of sex hormones, like testosterone, on stress and hostility factors have been primarily conducted in selected atypical populations such as violent criminals as well as androgen users and abusers. Therefore, the main aim of the current study was to investigate the association between testosterone levels and two psychosocial variables: stress and hostility in a cohort of healthy individuals who were members of a health maintenance organization (HMO).

METHODS: At five quarterly visits, psychosocial scales and blood draws were collected. Psychological stress was measured by using several scales that assessed different types of stress, including daily hassles, major life events and perceived stress. Similarly, different aspects of hostility were measured, among them cynicism, hostile affect and aggressive responding. Plasma collected from each visit was used for testosterone level determinations.

RESULTS: Testosterone levels were significantly associated with stress in both males and females. However, whereas this association exhibited a "threshold effect" in males, it demonstrated a direct and continuous linear relationship between these variables in females. Hostility was not correlated with testosterone levels in neither males nor females.

CONCLUSIONS: These results suggest that testosterone levels in normal males and females may be more reflective of an intricate balance between physiological responding and emotional coping to stressors than the hostility profile of the individual....

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