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Social Stress (social + stress)
Kinds of Social Stress Selected AbstractsSocial Stress Alters Expression of Large Conductance Calcium-Activated Potassium Channel Subunits in Mouse Adrenal Medulla and Pituitary GlandsJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2009O. Chatterjee Large conductance calcium-activated potassium (BK) channels are very prominently expressed in adrenal chromaffin and many anterior pituitary cells, where they shape intrinsic excitability complexly. Stress- and sex-steroids regulate alternative splicing of Slo-,, the pore-forming subunit of BK channels, and chronic behavioural stress has been shown to alter Slo splicing in tree shrew adrenals. In the present study, we focus on mice, measuring the effects of chronic behavioural stress on total mRNA expression of the Slo-, gene, two key BK channel , subunit genes (,2 and ,4), and the ,STREX' splice variant of Slo-,. As a chronic stressor, males of the relatively aggressive SJL strain were housed with a different unfamiliar SJL male every 24 h for 19 days. This ,social-instability' paradigm stressed all individuals, as demonstrated by reduced weight gain and elevated corticosterone levels. Five quantitative reverse transcriptase-polymerase chain assays were performed in parallel, including ,-actin, each calibrated against a dilution series of its corresponding cDNA template. Stress-related changes in BK expression were larger in mice tested at 6 weeks than 9 weeks. In younger animals, Slo-, mRNA levels were elevated 44% and 116% in the adrenal medulla and pituitary, respectively, compared to individually-housed controls. ,2 and ,4 mRNAs were elevated 162% and 194% in the pituitary, but slightly reduced in the adrenals of stressed animals. In the pituitary, dominance scores of stressed animals correlated negatively with , and , subunit expression, with more subordinate individuals exhibiting levels that were three- to four-fold higher than controls or dominant individuals. STREX variant representation was lower in the subordinate subset. Thus, the combination of subunits responding to stress differs markedly between adrenal and pituitary glands. These data suggest that early stress will differentially affect neuroendocrine cell excitability, and call for detailed analysis of functional consequences. [source] Hormone Responses to Social Stress in Abstinent Alcohol-Dependent Subjects and Social Drinkers with No History of Alcohol DependenceALCOHOLISM, Issue 7 2005Cynthia A. Munro Background: Previous studies have described blunted stress hormone responses after pharmacological activation of the hypothalamic-pituitary-adrenal (HPA) axis in sober alcoholics. The aim of the present study was to compare ACTH, cortisol, and prolactin responses to a psychological stressor in abstinent alcohol-dependent subjects matched to healthy control subjects. Methods: Individuals who met DSM-IV diagnostic criteria for a history of alcohol dependence but not for other axis I disorders were included in the study (n= 18; mean duration of abstinence ± SEM, 3.5 ± 5.7 years). Social drinkers (n= 23) served as control subjects. The sober alcohol-dependent and control subjects were matched for demographic measures including levels of stress symptoms. All subjects underwent the Trier Social Stress Test (TSST), a laboratory-based psychological stressor. Prestress and poststress plasma ACTH, cortisol, and prolactin levels, as well as a self-report measure of anxiety (State-Trait Anxiety Inventory), were obtained. Results: Nondepressed, abstinent alcoholics and control subjects did not differ with regard to age, racial composition, or baseline or poststress ratings of anxiety. Whereas ACTH and cortisol levels increased in response to the TSST, prolactin levels did not. Stress hormone response curves for the three hormones did not differ between the alcoholics and control subjects. Conclusions: When matched for levels of stress, a laboratory-based psychological stress test did not induce differential hormone response curves for abstinent alcoholics and control subjects. [source] Validity of the osu post-traumatic stress disorder scale and the behavior assessment system for children self-report of personality with child tornado survivors,PSYCHOLOGY IN THE SCHOOLS, Issue 2 2008Linda Garner Evans Tornadoes and other natural disasters can lead to anxiety and posttraumatic stress disorder (PTSD) in children. This study provides further validity for the Oklahoma State University Post-Traumatic Stress Disorder Scale,Child Form (OSU PTSDS-CF) by comparing it to the Behavior Assessment System for Children Self-Report of Personality (BASC-SRP). Correlations were significant at 0.01 between BASC-SRP scales of Anxiety, Atypicality, and Clinical Maladjustment, and at least 0.05 between OSU PTSDS-CF scales for Social Stress, Depression, Inadequacy, and Emotional Symptoms Index (ESI). Analyses of variance (ANOVAs) yielded significant differences at 0.01 between children with and without PTSD, based on OSU PTSDS-CF cut-off scores, for BASC-SRP Anxiety, Atypicality, and Clinical Maladjustment. ANOVAs were significant at 0.05 for Social Stress, Locus of Control, Relationship with Parents, and ESI. Results yielded moderate effect sizes, and BASC-SRP means were within normal limits for all groups. Practitioners are encouraged to supplement the BASC-SRP with PTSD measures in children who have experienced trauma. © 2008 Wiley Periodicals, Inc. [source] Social stress, visceral obesity, and coronary artery atherosclerosis: product of a primate adaptationAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2009Carol A. Shively Abstract Abdominal obesity is prevalent and often accompanied by an array of metabolic perturbations including elevated blood pressure, dyslipidemia, impaired glucose tolerance or insulin resistance, a prothrombotic state, and a proinflammatory state, together referred to as the metabolic syndrome. The metabolic syndrome greatly increases coronary heart disease (CHD) risk. Social stress also increases CHD although the mechanisms through which this occurs are not completely understood. Chronic stress may result in sustained glucocorticoid production, which is thought to promote visceral obesity. Thus, one hypothesis is that social stress may cause visceral fat deposition and the metabolic syndrome, which, in turn increases CHD. CHD is caused by coronary artery atherosclerosis (CAA) and its sequelae. Cynomolgus monkeys (Macaca fascicularis) are a well-established models of CAA. Social subordination may be stressful to cynomolgus monkeys and result in hypercortisolemia and exacerbated CAA in females. Herein is reviewed a body of literature which suggests that social stress increases visceral fat deposition in cynomolgus monkeys, that subordinate females are more likely than dominants to have visceral obesity, that females with visceral obesity have behavioral and physiological characteristics consistent with a stressed state, and that females with high ratios of visceral to subcutaneous abdominal fat develop more CAA. While these relationships have been most extensively studied in cynomolgus macaques, obesity-related metabolic disturbances are also observed in other primate species. Taken together, these observations support the view that the current obesity epidemic is the result of a primate adaptation involving the coevolution with encephalization of elaborate physiological systems to protect against starvation and defend stored body fat in order to feed a large and metabolically demanding brain. Social stress may be engaging these same physiological systems, increasing the visceral deposition of fat and its sequelae, which increase CHD risk. Am. J. Primatol. 71:742,751, 2009. © 2009 Wiley-Liss, Inc. [source] Chronic social stress in adolescence influenced both amphetamine conditioned place preference and locomotor sensitizationDEVELOPMENTAL PSYCHOBIOLOGY, Issue 5 2008I. Z. Mathews Abstract We previously reported that chronic social stress (SS) in adolescence, but not in adulthood, increased the locomotor-activating effects of nicotine in females, and not males, when tested in adulthood. However, SS rats had decreased locomotor response to nicotine when tested in adolescence. Here, we investigated age-related changes in the effects of SS on both conditioned place preference (CPP) and locomotor sensitization to amphetamine. In the CPP experiment, SS females tested in adolescence had increased preference for the 1.0 mg/kg dose of amphetamine, whereas SS rats of both sexes showed a decrease in CPP for the 0.5 mg/kg dose when tested as adults. Irrespective of time of testing, SS males and females had enhanced locomotor sensitization compared to controls. Thus, adolescent SS produced both immediate and enduring effects on behavioral responses to amphetamine, likely by altering the development of the mesocorticolimbic dopamine system, which holds implications for vulnerability to addiction. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 451,459, 2008. [source] Subtle gene,environment interactions driving paranoia in daily lifeGENES, BRAIN AND BEHAVIOR, Issue 1 2009C. J. P. Simons It has been suggested that genes impact on the degree to which minor daily stressors cause variation in the intensity of subtle paranoid experiences. The objective of the present study was to test the hypothesis that catechol- O -methyltransferase (COMT) Val158Met and brain-derived neurotrophic factor (BDNF) Val66Met in part mediate genetic effects on paranoid reactivity to minor stressors. In a general population sample of 579 young adult female twins, on the one hand, appraisals of (1) event-related stress and (2) social stress and, on the other hand, feelings of paranoia in the flow of daily life were assessed using momentary assessment technology for five consecutive days. Multilevel regression analyses were used to examine moderation of daily life stress-induced paranoia by COMT Val158Met and BDNF Val66Met genotypes. Catechol- O -methyltransferase Val carriers displayed more feelings of paranoia in response to event stress compared with Met carriers. Brain-derived neurotrophic factor Met carriers showed more social-stress-induced paranoia than individuals with the Val/Val genotype. Thus, paranoia in the flow of daily life may be the result of gene,environment interactions that can be traced to different types of stress being moderated by different types of genetic variation. [source] A Nursing Home in Arab-Israeli Society: Targeting Utilization in a Changing Social and Economic EnvironmentJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 1 2005Khalid Suleiman MD This article is a case study of the first 10 years of operation (1992,2002) of the Dabouriya Home for the Aged, the first publicly funded culturally adapted nursing home for Israeli citizens of Arab descent. Although 44% of Arab Israelis and 26% of Jewish Israelis aged 65 and older are disabled, in 1999, 4.3% of the Jewish population but only 0.7% of the Arab-Israeli population aged 65 or older lived in long-term care institutions; disabled Arab-Israeli elderly were mainly cared for by families. As Arab-Israeli society modernizes and traditional caregiving is reduced, alternatives must be found for this growing, disabled population. Medical and administrative records of 404 people admitted consecutively to a 136-bed facility over 10 years were analyzed. Two distinct segments of the needy population were served: people with independent activity of daily living (ADL) function but little or no family to provide help with intermediate ADLs and those dependent in ADLs and with health problems, especially dementia. Economic, demographic, and social changes in Arab-Israeli society may mean that traditional caregivers will not be able to adequately care for this highly disabled population. Administrators of the public health system in Israel should be aware of the underutilization of publicly funded long-term care by disabled Arab Israelis and the lack of care alternatives for the population that does use nursing homes, because there may be severe consequences in terms of caregiver burden and social stress when disabled elderly people remain in unsuitable environments. [source] Experimental infection magnifies inbreeding depression in house miceJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2008P. ILMONEN Abstract It is often assumed that inbreeding reduces resistance to pathogens, yet there are few experimental tests of this idea in vertebrates, and no tests for the effects of moderate levels of inbreeding more commonly found in nature. We mated wild-derived mice with siblings or first cousins and compared the resistance of their offspring to Salmonella infection with outbred controls under laboratory and seminatural conditions. In the laboratory, full-sib inbreeding reduced resistance to Salmonella and survivorship, whereas first-cousin inbreeding had no detectable effects. In competitive population enclosures, we found that first-cousin inbreeding reduced male fitness by 57% in infected vs. only 34% in noninfected control populations. Our study provides experimental evidence that inbreeding reduces resistance and ability to survive pathogenic infection, and moreover, it shows that even moderate inbreeding can cause significant fitness declines under naturalistic conditions of social stress, and especially with exposure to infectious agents. [source] Coat condition, housing condition and measurement of faecal cortisol metabolites , a non-invasive study about alopecia in captive rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2006Hanspeter W. Steinmetz Abstract Background, Previous studies have characterized alopecia in captive rhesus macaques (Macaca mulatta) by a mixed partial to complete alopecia in a bilateral symmetric pattern. Methods, In this study, coat condition assessments were related to exogenous and endogenous factors in captive rhesus macaques under different housing conditions in order to identify disturbances in environmental factors controlling or influencing hair growth. Additionally, the degree of alopecia was investigated in relation to adrenal endocrine function as an indicator of social stress using faecal glucocorticoid measurements. Results, Hair loss was found to vary with season and sex, was most pronounced in adult females during the winter and spring months. Generally, infants were not affected, but alopecia developed during adolescence. However, the housing system, available enclosure space and variations in group size and composition also appeared to influence coat condition. Levels of immunoreactive cortisol metabolites (11-oxoetiocholanolone) in faeces were significantly negatively correlated with alopecia, suggesting a relationship between hypothalamic-pituitary-adrenal (HPA) axis activity and hair loss in captive rhesus macaques. Conclusions, Although the present study demonstrates the influence of the HPA axis on coat condition, it is not known if hair loss is caused by abnormal behaviour or hormonal imbalances of the HPA axis itself. Our data suggest that alopecia in rhesus macaques is a highly complex multicausal disorder. [source] Changes in Hypothalamic-Pituitary-Adrenal Function, Body Temperature, Body Weight and Food Intake with Repeated Social Stress Exposure in RatsJOURNAL OF NEUROENDOCRINOLOGY, Issue 1 2006S. Bhatnagar Abstract These present studies aimed to compare changes in hypothalamic-pituitary-adrenal (HPA) activity and body temperature in response to acute social defeat, to repeated social stress and to novel restraint after repeated stress, as well as to assess effects on metabolic parameters by measuring body weight gain and food and water intake. We found that social defeat produced a marked increase in both adrenocorticotrophic hormone and corticosterone compared to placement in a novel cage. Similarly, body temperature was also increased during social defeat and during 30 min of recovery from defeat. We then examined the effects of 6 days of repeated social stress and observed minimal HPA responses to repeated social stress compared to control rats. These neuroendocrine responses were contrasted by robust increases in body temperature during stress and during recovery from stress during 6 days of repeated stress. However, in response to novel restraint, repeatedly stressed rats displayed facilitated body temperature responses compared to controls, similar to our previous findings with HPA activity. Food intake was increased during the light period during which defeat took place, but later intake during the dark period was not affected. Repeated stress decreased body weight gain in the dark period but food intake was increased overall during the 6 days of repeated stress in the light period. As a result, repeated stress increased cumulative food intake during the light period in the stressed rats but these relatively small increases in food intake were unable to prevent the diminished total weight gain in repeatedly stressed rats. Overall, the results demonstrate that, although acute social defeat has similar effects on temperature and HPA activity, repeated exposure to social stress has divergent effects on HPA activity compared to body temperature and that dampened weight gain produced by repeated social stress cannot be fully explained by changes in food intake. [source] Effects of escitalopram on the regulation of brain-derived neurotrophic factor and nerve growth factor protein levels in a rat model of chronic stressJOURNAL OF NEUROSCIENCE RESEARCH, Issue 11 2009Olaf Schulte-Herbrüggen Abstract Escitalopram (ES-CIT) is a widely used, highly specific antidepressant. Until now there has been very little evidence on how this drug under pathological conditions affects an important feature within the pathophysiology of stress-related disorders such as depression: the endogenous neurotrophins. By using a well-characterized rat model in which chronic stress induces depressive-like behavior, the levels of neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were determined in representative brain regions and serum using a highly sensitive improved fluorometric two-site ELISA system. There was a significant increase of BDNF in the left and right cortices after stress treatment (twofold increase) that was reversed by application of ES-CIT. An ES-CIT-dependent NGF reduction in stressed rats was detectable in the right cortex only (P = 0.027). The left hippocampus revealed significantly higher amounts of BDNF (2.5-fold increase) protein than the right hippocampus. These interhemispheric differences were unrelated to stress or ES-CIT treatment in all animals. BDNF and NGF of the frontal cortex, cerebellum, and serum did not change between the study groups. There was a negative correlation between body weight and serum BDNF, independent of stress or ES-CIT treatment. In conclusion, BDNF and NGF show substantial changes in this rodent model of chronic social stress, which is susceptible to antidepressant treatment with ES-CIT and therefore may constitute a neurobiological correlate for the disease. © 2009 Wiley-Liss, Inc. [source] Psychological Research on Homelessness in Western Europe: A Review from 1970 to 2001JOURNAL OF SOCIAL ISSUES, Issue 3 2007Pierre Philippot The rapidly growing, but still small, research literature on homelessness in Europe has often been provided by non-academics, using qualitative methods, and has been published in sources that are not widely available. This article summarizes definitions employed, observed prevalence, the socio-demographic characteristics, and the physical and mental health status of the homeless in Western Europe. Research pertaining to the causes of homelessness and the societal response to the problem are also reviewed, and the ethical and methodological questions raised by European researchers are debated. A critical analysis of the largely descriptive European research is provided, and some noteworthy exceptions are described. We also discuss a number of promising theoretical models, including those that focus on learned helplessness, social strain, and social stress. [source] African American women's beliefs about mental illness, stigma, and preferred coping behaviors,RESEARCH IN NURSING & HEALTH, Issue 5 2009Earlise C. Ward Abstract We examined African American women's representations/beliefs about mental illness, preferred coping behaviors if faced with mental illness, whether perceived stigma was associated with treatment-seeking, and if so, whether it was related to beliefs and coping preference, and whether these variables differed by age group. Participants were 185 community-dwelling African American women 25 to 85 years of age. Results indicated the women believed that mental illness is caused by several factors, including family-related stress and social stress due to racism, is cyclical, and has serious consequences but can be controlled by treatment. Participants endorsed low perceptions of stigma. Major preferred coping strategies included praying and seeking medical and mental health care. Age differences were found in all variables except stigma. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:480,492, 2009 [source] Effects of reproductive condition and dominance rank on cortisol responsiveness to stress in free-ranging female rhesus macaquesAMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2010Christy L. Hoffman Abstract The hypothalamic,pituitary,adrenal (HPA) axis modulates individuals' physiological responses to social stress, which is an inevitable aspect of the daily lives of group-living animals. Previous nonhuman primate studies have reported that sex, age, rank, and reproductive condition influence cortisol levels under stressful conditions. In this study we investigated cortisol responses to stress among 70 multiparous, free-ranging female rhesus macaques (Macaca mulatta) on the island of Cayo Santiago, PR. Plasma cortisol samples were collected in two consecutive years under similar conditions. Twenty-two females were sampled both years, and most of those females were lactating in only one of the years. Individual differences in cortisol levels were stable across years, even though reproductive condition changed for most individuals. No relationship was found between age or social rank and cortisol levels. Of the females that changed reproductive conditions, cortisol levels were higher when they were lactating than when they were cycling, and the amount of change in cortisol from cycling to lactating was greatest for low-ranking individuals. Heightened reactivity to stress during lactation may be the result of concerns about infant safety, and such concerns may be higher among low-ranking mothers than among higher ranking mothers. Psychosocial stress and hyperactivation of the HPA axis during lactation can suppress immune function and increase vulnerability to infectious diseases, thus explaining why adult females in the free-ranging rhesus macaque population on Cayo Santiago have a higher probability of mortality during the birth season than during the mating season. Am. J. Primatol. 72:559,565, 2010. © 2009 Wiley-Liss, Inc. [source] Cannibalism in wild bonobos (Pan paniscus) at Lui KotaleAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010Andrew Fowler Abstract We describe the cannibalization of an infant bonobo (circa 2.5 years old) at Lui Kotale, in the Democratic Republic of Congo. The infant died of unknown causes and was consumed by several community members including its mother and an older sibling one day after death. Certain features concerning the pattern of consumption fit in with previously observed episodes of cannibalism in Pan, whereas others, such as the mother's participation in consuming the body, are notable. The incident suggests that filial cannibalism among apes need not be the result of nutritional or social stress and does not support the idea that filial cannibalism is a behavioral aberration. Am. J. Primatol. 72:509,514, 2010. © 2010 Wiley-Liss, Inc. [source] The unique value of primate models in translational researchAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2009Carol A. Shively Abstract This special issue of AJP is focused on research using nonhuman primates as models to further the understanding of women's health. Nonhuman primates play a unique role in translational science by bridging the gap between basic and clinical investigations. The use of nonhuman primates in biomedical research challenges our resolve to treat all life as sacred. The scientific community has responded by developing ethical guidelines for the care and the use of primates and clarifying the responsibility of investigators to insure the physical and psychological well-being of nonhuman primates used in research. Preclinical investigations often involve the use of animal models. Rodent models have been the mainstay of biomedical science and have provided enormous insight into the workings of many mammalian systems that h ave proved applicable to human biological systems. Rodent models are dissimilar to primates in numerous ways, which may limit the generalizability to human biological systems. These limitations are much less likely in nonhuman primates and in Old World primates, in particular, Macaques are useful models for investigations involving the reproductive system, bioenergetics, obesity and diabetes, cardiovascular health, central nervous system function, cognitive and social behavior, the musculoskeletal system, and diseases of aging. This issue considers primate models of polycystic ovary syndrome; diet effects on glycemic control, breast and endometrium; estrogen, reproductive life stage and atherosclerosis; estrogen and diet effects on inflammation in atherogenesis; the neuroprotective effects of estrogen therapy; social stress and visceral obesity; and sex differences in the role of social status in atherogenesis. Unmet research needs in women's health include the use of diets in nonhuman primate studies that are similar to those consumed by human beings, primate models of natural menopause, dementia, hypertension, colon cancer, and frailty in old age, and dedicated colonies for the study of breast cancer. Am. J. Primatol. 71:715,721, 2009. © 2009 Wiley-Liss, Inc. [source] Social stress, visceral obesity, and coronary artery atherosclerosis: product of a primate adaptationAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2009Carol A. Shively Abstract Abdominal obesity is prevalent and often accompanied by an array of metabolic perturbations including elevated blood pressure, dyslipidemia, impaired glucose tolerance or insulin resistance, a prothrombotic state, and a proinflammatory state, together referred to as the metabolic syndrome. The metabolic syndrome greatly increases coronary heart disease (CHD) risk. Social stress also increases CHD although the mechanisms through which this occurs are not completely understood. Chronic stress may result in sustained glucocorticoid production, which is thought to promote visceral obesity. Thus, one hypothesis is that social stress may cause visceral fat deposition and the metabolic syndrome, which, in turn increases CHD. CHD is caused by coronary artery atherosclerosis (CAA) and its sequelae. Cynomolgus monkeys (Macaca fascicularis) are a well-established models of CAA. Social subordination may be stressful to cynomolgus monkeys and result in hypercortisolemia and exacerbated CAA in females. Herein is reviewed a body of literature which suggests that social stress increases visceral fat deposition in cynomolgus monkeys, that subordinate females are more likely than dominants to have visceral obesity, that females with visceral obesity have behavioral and physiological characteristics consistent with a stressed state, and that females with high ratios of visceral to subcutaneous abdominal fat develop more CAA. While these relationships have been most extensively studied in cynomolgus macaques, obesity-related metabolic disturbances are also observed in other primate species. Taken together, these observations support the view that the current obesity epidemic is the result of a primate adaptation involving the coevolution with encephalization of elaborate physiological systems to protect against starvation and defend stored body fat in order to feed a large and metabolically demanding brain. Social stress may be engaging these same physiological systems, increasing the visceral deposition of fat and its sequelae, which increase CHD risk. Am. J. Primatol. 71:742,751, 2009. © 2009 Wiley-Liss, Inc. [source] The relationship between socio-sexual behavior and salivary cortisol in bonobos: tests of the tension regulation hypothesisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2009Gottfried Hohmann Abstract Bonobos are known for their pacifistic behavior and their large repertoire of behaviors that are thought to serve conflict resolution. One is an unusual form of ventro-ventral mounting that facilitates genital contacts (GC). Various hypotheses have been proposed to explain its function. In this study we tested predictions of the tension regulation hypothesis using salivary cortisol as a marker for social stress. The results indicate a temporal relationship between GC and cortisol levels. Compared with baseline data and matched samples of unrestricted food access, rates of GC increased when access to food sources was restricted. Cortisol levels were highest when access to food was constrained. However, because the behavioral and hormonal responses occurred when viewing the stimulus at a distance and preceded the physical presence of the stimulus, we conclude that the anticipation of a competitive situation was sufficient to induce social stress. Contrary to our prediction, targets of aggression did not have higher rates of GC nor did they solicit GC more often than others. Furthermore, higher GC rates did not correlate with a more pronounced decrease in cortisol levels. Not all results obtained in this study supported the predictions concerning the regulatory function of GC on social tension and further research is needed to explore this question. However, the results indicate that the anticipation of competition may be sufficient to induce a costly physiological response, and that high levels of resource competition may have lasting effects on physical stress and stress management. Am. J. Primatol. 71:223,232, 2009. © 2008 Wiley-Liss, Inc. [source] Factors affecting fecal glucocorticoid levels in semi-free-ranging female mandrills (Mandrillus sphinx)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2008Joanna M Setchell Abstract Subordinate female cercopithecine primates often experience decreased reproductive success in comparison with high-ranking females, with a later age at sexual maturity and first reproduction and/or longer interbirth intervals. One explanation that has traditionally been advanced to explain this is high levels of chronic social stress in subordinates, resulting from agonistic and aggressive interactions and leading to higher basal levels of glucocorticoids. We assessed the relationships among fecal cortisol levels and reproductive condition, dominance rank, degree of social support, and fertility in female mandrills (Mandrillus sphinx) living in a semi-free-ranging colony in Franceville, Gabon. Lower-ranking females in this colony have a reproductive disadvantage relative to higher-ranking females, and we were interested in determining whether this relationship between dominance rank and reproductive success is mediated through stress hormones. We analyzed 340 fecal samples from 19 females, collected over a 14-month period. We found that pregnant females experienced higher fecal cortisol levels than cycling or lactating females. This is similar to results for other primate species and is likely owing to increased metabolic demands and interactions between the hypothalamus,pituitary,adrenal axis, estrogen, and placental production of corticotrophin releasing hormones during pregnancy. There was no influence of dominance rank on fecal cortisol levels, suggesting that subordinate females do not suffer chronic stress. This may be because female mandrills have a stable social hierarchy, with low levels of aggression and high social support. However, we found no relationship between matriline size, as a measure of social support, and fecal cortisol levels. Subordinates may be able to avoid aggression from dominants in the large enclosure or may react only transiently to specific aggressive events, rather than continuously expecting them. Finally, we found no relationship between fecal cortisol levels and fertility. There was no difference in fecal cortisol levels between conceptive and nonconceptive cycles, and no significant relationship between fecal cortisol level and either the length of postpartum amenorrhea or the number of cycles before conception. This suggests that the influence of dominance rank on female reproductive success in this population is not mediated through chronic stress in subordinate females, and that alternative explanations of the relationship between social rank and reproduction should be sought. Am. J. Primatol. 70:1023,1032, 2008. © 2008 Wiley-Liss, Inc. [source] Response of the hypothalamic,pituitary,adrenal axis to psychological stress in patients with psoriasisBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2005H.L. Richards Summary Background, Psoriasis may, in some patients, be triggered and/or exacerbated by stress. Objectives, As activation of the hypothalamic,pituitary,adrenal (HPA) axis is critical to a successful stress response we investigated this in patients with psoriasis. Methods, Forty patients with chronic plaque psoriasis and 40 age-matched normal controls experienced three randomly presented acute psychological stressors (cognitive, emotional and social). Serial serum cortisol, pulse rate and blood pressure assessments were undertaken at baseline and following each of the stressors. Salivary cortisol samples were collected at 09·00 h on the day of testing. Results, In control subjects there was a significant (r = 0·38; P < 0·05) correlation between pulse rate and serum cortisol level following the social performance stressor; this was not evident in the psoriasis group (r = 0·07; not significant). Patients who believed that their psoriasis was highly stress responsive had significantly lower salivary cortisol levels at baseline (P < 0·01) and lower serum cortisol levels following the social performance stressor (P = 0·016) than patients with nonstress-responsive disease who believed that stress had no impact. In contrast, there was no difference between the groups for change in pulse rate poststressor. Conclusions, This study shows that patients with psoriasis, and in particular those whose disease appears to be stress responsive, exhibit an altered HPA response to acute social stress. The implication is that such patients may perhaps be primed to flares of their psoriasis. Whether this is genetically predetermined and/or a consequence of the distress of living with psoriasis remains to be determined. [source] Reproduction and Resistance to Stress: When and HowJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2003J. C. Wingfield Abstract Environmental and social stresses have deleterious effects on reproductive function in vertebrates. Global climate change, human disturbance and endocrine disruption from pollutants are increasingly likely to pose additional stresses that could have a major impact on human society. Nonetheless, some populations of vertebrates (from fish to mammals) are able to temporarily resist environmental and social stresses, and breed successfully. A classical trade-off of reproductive success for potential survival is involved. We define five examples. (i) Aged individuals with minimal future reproductive success that should attempt to breed despite potential acute stressors. (ii) Seasonal breeders when time for actual breeding is so short that acute stress should be resisted in favour of reproductive success. (iii) If both members of a breeding pair provide parental care, then loss of a mate should be compensated for by the remaining individual. (iv) Semelparous species in which there is only one breeding period followed by programmed death. (v) Species where, because of the transience of dominance status in a social group, individuals may only have a short window of opportunity for mating. We suggest four mechanisms underlying resistance of the gonadal axis to stress. (i) Blockade at the central nervous system level, i.e. an individual no longer perceives the perturbation as stressful. (ii) Blockade at the level of the hypothalamic-pituitary-adrenal axis (i.e. failure to increase secretion of glucocorticosteroids). (iii) Blockade at the level of the hypothalamic-pituitary-gonad axis (i.e. resistance of the reproductive system to the actions of glucocorticosteroids). (iv) Compensatory stimulation of the gonadal axis to counteract inhibitory glucocorticosteroid actions. Although these mechanisms are likely genetically determined, their expression may depend upon a complex interaction with environmental factors. Future research will provide valuable information on the biology of stress and how organisms cope. Such mechanisms would be particularly insightful as the spectre of global change continues to unfold. [source] | ||||||||||||||||