Stress-induced salivary cortisol secretion during hypobaric hypoxia challenge and in vivo urinary thromboxane production in healthy male subjects

Few studies have assessed the effects of stress on in vivo platelet activation. In the present study, hypobaric hypoxia induced by rapid decompression during high-altitude simulated flight in a hypobaric chamber was used to evaluate the effects of environmental stress on salivary cortisol and urinary thromboxane metabolite (TXM) excretion, a noninvasive marker of in vivo platelet function. Twenty-one male aviators (mean ± SD age = 36 ± 7 years) experiencing hypoxia by removing their oxygen mask for 4-5 min during a simulated flight to 25,000 ft (7,620 m; pO(2) = 59.17 mmHg) and a matched control group of thirteen flying instructors wearing oxygen masks during the challenge, were studied. Hypobaric hypoxia induced a transient significant increase (P < 0.001) in the aviators' salivary cortisol concentration; the overall pattern of diurnal cortisol fluctuation was maintained in both groups. Urinary TXM showed a significant ～30% reduction (P < 0.01) after the chamber session in aviators exposed to hypobaric hypoxia, but not in controls. A significant inverse correlation was found between salivary cortisol and urinary TXM in aviators (r = - 0.64, P = 0.0015). Salivary cortisol was a significant predictor (P < 0.001) for urinary TXM concentrations in aviators. In conclusion, here we observed that an acute stress-induced salivary cortisol increase was associated with reduced urinary thromboxane biosynthesis, providing the first indirect evidence for an inhibitory effect of acute stress on in vivo platelet function.     

Differences between diurnal patterns of salivary cortisol and dehydroepiandrosterone in healthy female adolescents

The adrenal hormones cortisol and dehydroepiandrosterone (DHEA) share a common secretagogue: adrenocorticotropic hormone; however, secretion of these hormones can be dissociated suggesting subtle individual regulation at the level of the adrenal gland. We examined differences in the diurnal patterns of cortisol and DHEA secretion in healthy adolescent girls, with the aim of informing the possibility of exploiting these differences to aid interpretation of data from clinical populations in which these patterns can become dysregulated. Fifty-six healthy females aged 10-18 years provided saliva samples at 0 and 30 min (morning samples) and 12 h post-awakening on 2 consecutive weekdays. For morning salivary cortisol in relation to morning DHEA concentrations, correlational analysis revealed only a trend (p = 0.054). Similarly, the association between evening cortisol and DHEA was characterised as a trend (p = 0.084). Mean morning DHEA concentrations showed more day-to-day consistency than equivalent cortisol samples (r = 0.829 for DHEA and 0.468 for cortisol; z = 3.487, p < 0.0005). Unlike the cortisol pattern, characterised by a marked awakening response (cortisol awakening response, CAR), a significant rise in DHEA concentration post-awakening was not evident. Finally, there was a strong association between morning and evening concentrations of DHEA, not found for cortisol. The study shows differences in cortisol and DHEA secretion in the post-awakening period and informs work that seeks to examine correlates of dysregulated hypothalamic-pituitary-adrenal axis function. Parallel examination of both hormones enables enhanced interpretation of aberrant patterns of the CAR, i.e. an exploration of whether dysregulation affects both hormones (reflecting overall steroidogenic capacity) or cortisol alone (CAR-specific mechanisms).     

The effect of mother-infant skin-to-skin contact on plasma cortisol and β-endorphin concentrations in preterm newborns

The aim of this study was to assess the effect of mother-infant skin-to-skin contact on plasma β- endorphin and cortisol concentrations in stable, preterm infants on a newborn intensive care unit. Blood samples were obtained before and at the end of a 20-min period of skin-to-skin contact. Similarly paired samples, obtained at the same times and after the same interval, without skin-to- skin contact, were obtained on another day and served as controls. Both cortisol and β-endorphin concentrations fell significantly after the skin-to-skin session (cortisol: geometric mean change 66%, p=0.008; β-endorphin: geometric mean change 74%, p=0.002). There was also a significant fall in cortisol levels during the control session (geometric mean change 78%, p=0.02), in contrast to β-endorphin levels, in which there was no significant change. Analysis of variance showed that the fall in β-endorphin, but not the fall in cortisol, during the skin-to-skin session was significant when compared with the control session. These results emphasize the hormonal responsiveness of the preterm newborn to relatively minor interventions. We conclude that maternal skin-to-skin contact results in a significant reduction in circulating β-endorphin in the newborn; there was no evidence of any adverse effect.     

Morningness–eveningness orientation and attitude change: Evidence for greater systematic processing and attitude change at optimal time-of-day

This study examines the relationship between morningness–eveningness orientation and time-of day on attitude change, and tests the hypothesis that people will be more persuaded when tested at their optimal time-of-day (i.e., morning for M-types and evening for E-types) than non-optimal time-of-day (i.e., evening for M-Types and morning for E-types). Two hundred and twenty participants read a message that contained either strong vs. weak quality counter-attitudinal arguments (anti-voluntary euthanasia) in the morning (9.00 a.m.) or in the evening (7.00 p.m.). When tested at their respective optimal time-of-day (for both M- and E-types) there was a reliable difference in attitude change between the strong vs. weak messages (indicating message processing had occurred) while there was no difference between strong vs. weak messages when tested at their non-optimal time-of-day. In addition, the amount of message-congruent thinking mediated the attitude change. The results show that M- and E-types pay greater attention to and elaborate on a persuasive message at their optimal time-of-day, and this leads to increased attitude change, compared to those tested at their non-optimal time-of-day.     

东莨菪碱对吗啡诱导的大鼠行为敏感化的影响

药物重复处理导致的行为敏感化与成瘾过程密切相关。本实验检验东莨菪碱对吗啡诱导的大鼠行为敏感化发展和转化的影响。实验一动物分为3组,分别进行生理盐水（对照组）、吗啡（10mg/kg,吗啡组）、吗啡（10mg/kg）＋东莨菪碱（3mg/kg,吗啡-东莨菪碱组）前处理,36小时腹腔注射4次（第1~2天）。自然戒断7天（第3~9天）。第10天,所有动物均使用吗啡（4mg/kg）激发,记录动物的自发活动量;第24天,吗啡组和吗啡-东莨菪碱组动物重复第10天的操作。实验二动物分为3组,分别接受生理盐水（对照组）、吗啡（10mg/kg,吗啡组）、吗啡（10mg/kg,吗啡-东莨菪碱组）处理,36小时腹腔注射4次（第1~3天）;间隔12小时后,3组动物分别接受生理盐水、生理盐水和东莨菪碱（3mg/kg）处理,仍为36小时腹腔注射4次（第3 ~5天）。第6~9天不进行药物处理。第10天和第17天,分别使用吗啡（4mg/kg）激发,记录动物的活动量。记录时间均为两小时(10分钟为一个记录单元)。结果表明,东莨菪碱能够抑制吗啡诱导的行为敏感化的发展,一定程度上也能够延缓行为敏感化的转化但没有阻断这种转化     

Sex differences of salivary cortisol secretion in patients with major depression

Depression is associated with increased cortisol secretion and occurs more often in women than in men. Thus, it has been hypothesized that differences in cortisol secretion might, in part, be responsible for the greater risk of developing depression in women. However, only few studies have examined sex differences in baseline cortisol secretion in depressed patients and healthy controls. We examined sex effects on cortisol secretion in 52 medication-free patients with major depression (37 women, 15 men, mean ± SD age 35 ± 11 years, Hamilton Depression Scale mean score 27 ± 5) and 50 healthy age- and sex-matched control subjects. Salivary cortisol concentrations were measured at 8:00, 12:00, 16:00, and 22:00 h. Repeated measures analysis of covariance revealed a group × sex interaction (p = 0.05). Post hoc tests revealed higher cortisol concentrations in depressed compared to healthy men [F(1;29) = 7.5, p = 0.01]. No differences were found between depressed and non-depressed women. Our results do not support the hypothesis that differences in cortisol secretion between depressed and non-depressed subjects are more pronounced in women than in men. Study characteristics and methods as well as sex-specific confounding variables such as menstrual cycle, menopause and the use of oral contraceptives may account for inconclusive results across studies.     

积极道德情绪和年龄对3-5岁幼儿安慰行为的影响

大量研究已经表明,消极道德情绪可以促进幼儿的亲社会行为,但积极道德情绪对幼儿亲社会行为的促进作用仍然缺乏全面探索。安慰行为是幼儿的典型亲社会行为,本研究使用实验法,采取想象启动和实际启动两种范式,考察积极道德情绪对3-5岁257名幼儿的安慰行为的影响。研究发现,幼儿的安慰行为发展具有年龄特征,4岁是幼儿安慰行为发展的转变关键期,更有意义的是,研究证明积极道德情绪对幼儿的安慰行为具有促进效应。本研究结果能为有效培养儿童的安慰行为提供有益建议。     

Continuity and Change in Emotional Reactivity in Rhesus Monkeys Throughout the Prepubertal Period

We examined continuity and change in emotional reactiviy as assessed by hypothalamic–pituitary–adrenal (HPA) activity in rhesus monkeys. Plasma samples were obtained from mother-peer–reared and surrogate-peer–reared monkeys and assayed for cortisol concentrations at 5 time points in infancy. Both plasma and saliva samples were collected for cortisol assay from the same monkeys as 1-, 2-, and 3-year-old juveniles, respectively. Plasma cortisol concentrations increased during the first 5 months of life and decreased from 1 to 3 years of age. Females consistently had higher plasma cortisol concentrations than males. Plasma cortisol concentrations were lower in surrogate-peer–reared than mother-peer–reared monkeys during the first month of life. Juvenile plasma cortisol concentrations were significantly correlated with infant cortisol levels at all but the earliest time point. Analysis of salivary cortisol from a subset of animals showed a similar age-related decline and the presence of a significant rearing effect, with lower concentrations in surrogate-peer–reared juveniles, but no sex difference. Salivary and plasma cortisol concentrations in these animals were significantly correlated.     

Visuo-spatial path learning,stress, and cortisol secretion following military cadets’ first parachute jump: the effect of increasing task complexity

The present field experiment examined how multi-trial visuo-spatial learning and memory performance are impacted by excessive arousal, instigated by a potentially life-threatening event (i.e., a first parachute jump). Throughout a parachute training activity, subjective and neuroendocrine (i.e., cortisol) stress levels were assessed of 61 male military cadets who were randomly assigned to a control (n = 30) or a jump stress condition (n = 31). Post-stress learning and memory capacity was assessed with a 10-trial path-learning task that permitted emergence of learning curves. Pre-activity cortisol concentrations indicated a significant neuroendocrine anticipatory stress response in the stress group. Following parachuting, subjective stress levels and salivary cortisol reactivity differed significantly between groups. Visuo-spatial path-learning performance was impaired significantly after jump stress exposure, relative to the control group. Moreover, examination of the learning curves showed similar learning and memory performance at onset of the trials, with curves bifurcating as the task became more complex. These findings are in accordance with leading theories that acknowledge a moderating effect of task complexity. In sum, the present study extends knowledge concerning anticipatory stress effects, endogenously instigated cortisol reactivity, and the influence of extreme arousal on visuo-spatial path learning.     

Resilience and hypothalamic-pituitary-adrenal axis reactivity under acute stress in young men

The present study examined the relationship between resilience (measured using the Resilience Scale for Adults) and hypothalamic-pituitary-adrenal (HPA) axis reactivity. We examined the subjective and cortisol responses of 28 healthy young men to an acute stressor (public speech task). Eight saliva samples were collected in order to obtain the response curve (anticipation, reactivity, recuperation) for each subject. ANOVA indicated that highly resilient individuals tended to display less mood deterioration than less resilient individuals (marginal p(time x group interaction) = 0.075). They also revealed that the former tended to secrete less cortisol overall than the latter during the experiment (marginal p(main group effect) = 0.087) but this effect was not uniform across time (p(time x group interaction) = 0.029). Additional analyses performed to identify the source of this interaction revealed that resilience moderates cortisol secretion in anticipation of the stressor (i.e. highly resilient individuals secreted less cortisol than less resilient ones, p = 0.05) but that it is not conductive to lower HPA reactivity amidst stress (i.e. there was no difference between groups in the increase in cortisol secretion from baseline to peak). The recovery slopes were likewise not statistically different. The implications of these findings regarding health are discussed.     

Effect of pre- and postcompetition emotional state on salivary cortisol in top-ranking wrestlers

The purpose was three-fold: (1) to investigate the effect of baseline, precompetition, and postcompetition stress on salivary cortisol levels in top-ranking Brazilian wrestlers (N = 17) participating in a national competition; (2) to estimate correlations among three stress measures (perceived stress, salivary cortisol, and physiological stress reaction); and (3) to compare cortisol concentrations between losers and winners. Salivary cortisol was collected at baseline, pre-, and postcompetition. Physiological stress reaction and perceived stress scores were measured just before warm-up for the competition. Analysis showed a significant main effect for testing time. Correlations among the stress measures were not significant. Analysis of covariance between the winners (n = 10) and the losers (n = 7) was also not significant. Salivary cortisol concentrations increased after the intense exercise of competition. The wrestlers did not perceive any physiological effects.     

Cognitively-Based Compassion Training for parents reduces cortisol in infants and young children

This study tests a group-based secular contemplative practice intervention, Cognitively-Based Compassion Training (CBCT), with parents of young children. We report on a randomized controlled preliminary efficacy study. Certified teachers administered CBCT for 20 hr across 8 to 10 weeks in two cohorts of parents with infants and young children. The intervention group was compared to a waitlist control group. Thirty-nine parents and their children, who ranged in age from 4 months to 5 years, were evaluated at pre- and postintervention (n = 25 intervention, n = 14 waitlist control) on hair cortisol concentration. Parents also completed self-administered questionnaires at both time points regarding demographics, physical symptoms of stress, parenting stress, self-compassion, and mindfulness. Children of parents in the CBCT group experienced significant decreases in cortisol at the postintervention assessment, as compared with the control group. However, parent cortisol and self-report measures did not significantly change other than a small effect on clinical levels of parenting stress. CBCT may be a positive new way to intervene with parents to lower infants’ and young children's cumulative physiological stress.     

Stability of pace and turn parameters of elite long-distance swimmers

This study aimed to assess the stability of the performance, pace and turn parameters of elite long-distance male swimmers during an 800 m freestyle race. The sample was composed by 38 male swimmers, participating in the 800 m event at the 2016 LEN European Aquatic Championships (long course meter). The performance, and a set of pace and turn parameters were analyzed. A customized software was used to perform each race analysis. Swimmers spent 64.05 ± 0.50% and 35.95 ± 0.49% of the final race time in the clean swim and turns, respectively. In the pace parameters, the clean swim was the only one that did not differ between the first and second half of the race (1.63 ± 0.05 vs 1.62 ± 0.05 m·s⁻¹), and in the turn parameters, the water break distance was also similar (5.13 ± 1.17 vs 5.06 ± 0.98 m). A significant and moderate-strong variation was verified for the performance (total race lap effect: p < 0.001, η² = 0.62), and a significant and moderate variation for the pace parameters (total race: p < 0.001, 0.15 ≤ η² ≤ 0.33), and for the turn parameters (total race: p < 0.01, 0.15 ≤ η² ≤ 0.33). Present data (pace and turn variation) shows that elite long-distance male swimmers do not maintain a similar pattern during an 800 m freestyle race. Future research is need to understand if this lack of pace and turn stability is the best way to enhance the performance, or if swimmers should be advised to control their pace and turn. Nevertheless, coaches are advised to help swimmers with feedback about their pace (i.e., controlling the intermediate 30 m) and turn performances (i.e., controlling the 5 m in and 15 m out), leading to a positive effect in their final race time.     

Serum testosterone,cortisol, glucose,and ethanol in males arrested for spouse abuse

Concentrations of ethanol, testosterone, cortisol, and glucose were determined in serum obtained from 16 males taken into police custody after incidents of spouse abuse. The mean blood ethanol level at the time of arrest was 33.3 ± 2.6 mM. Serum testosterone levels were significantly lower and cortisol levels higher at the time of police intervention (within 1 hour of the incident) compared to control data collected later from the subjects when sober. Offenders did not differ from a group of nonviolent pub patrons at similar blood ethanol levels (35.9 ± 4.5 mM) with respect to serum testosterone, cortisol, or glucose, but their sober state cortisol and glucose concentrations were significantly higher compared to a control group of nonalcoholic men. Intoxication or acute hormonal changes were thus not specifically associated with violent behaviour. Provocative cues, however, may have been more frequent in the offender families, as Straus Conflict Tactics data showed that offenders and victims resorted to verbal aggression significantly more often than control families. The significantly elevated cortisol and glucose concentrations in offenders when sober compared to nonviolent controls could be viewed as direct effects of life stress, or as indirect effects of stress mediated by learned escape drinking. Excessive drinking as well as spouse abuse could be maladaptive coping strategies that principally serve to maintain the status quo, physiologically as well as psychologically. © 1992 Wiley-Liss, Inc.     

Stress and stereotypic behaviour in mink (Mustela vison): a focus on adrenocortical activity

We examined whether female mink with low (LS) and high (HS) occurrence of stereotypic behaviour differ in their adrenocortical activity in baseline conditions or in response to immobilisation (Experiment 1), handling, adrenocorticotropic hormone (ACTH) challenge (Experiment 2) and excretion of circulating cortisol (Experiment 3). Faeces are the predominating excretory route of cortisol (83%), with peak concentrations after 4.2 h (urine: 3.4 h). Faecal cortisol metabolites (FCMs) reflected changes in relation to handling/ACTH challenge. In Experiment 1 (n = 162), HS mink had approximately 54% higher baseline level of FCM than LS mink (P < 0.001), with markedly elevated FCM on the days after an immobilisation stressor. In Experiment 2 (n = 48), LS and HS mink did not differ in adrenocortical activity after an ACTH challenge. However, HS mink reacted more in response to handling, evident in the FCM level 4-20 h after the handling (P = 0.001). In Experiment 3 (n = 16), the excretion of infused (3)H-cortisol did not differ between LS and HS mink. Stereotypic behaviour is concurrent with higher baseline concentrations of FCM, which cannot be explained by a greater adrenocortical reactivity or a different excretion of the circulating cortisol. Instead, we conclude that mink with a high level of stereotypic behaviour have a greater perception of stress, or increased sensitivity to stressors at the pituitary level.     

Acute consolidation stress enhances reality monitoring in healthy young adults

Source monitoring refers to cognitive processes involved in making attributions about the origins of memories, knowledge, and beliefs. One particular type of source monitoring with ample practical significance is reality monitoring, i.e., the ability to discriminate between internally vs. externally generated memories. Abundant evidence indicates that exposure to acute stress enhances declarative memory consolidation. To date, no study has looked at whether exposure to acute stress during the consolidation phase may promote reality monitoring performance. The authors examined this by administering cold pressor stress (CPS) or a control procedure to participants (N = 80) after they had either performed or only imagined performing simple motor acts, and assessing reality monitoring 24 h later. When compared with the control condition, CPS significantly elevated salivary free cortisol concentrations and enhanced reality monitoring. Stress-induced cortisol responses, however, were found not to be related to improved reality monitoring performance. Our findings are consistent with the view that post-learning stress hormone-related activity may modulate source memory consolidation.     

The presence of a best friend buffers the effects of negative experiences

The goal of the current study was to examine how the presence of a best friend might serve as protection against the effect of negative experiences on global self-worth and the hypothalamic-pituitary-adrenocortical axis (HPA axis). A total of 103 English-speaking male (n = 55) and female (n = 48) participants from Grade 5 (M = 10.27 years) and Grade 6 (M = 11.30 years) completed booklets about their experiences that occurred 20 min previously and how they felt about themselves at the moment, and they provided saliva multiple times per day over the course of 4 consecutive days. Having a best friend present during an experience significantly buffered the effect of the negativity of the experience on cortisol and global self-worth. When a best friend was not present, there was a significant increase in cortisol and a significant decrease in global self-worth as the negativity of the experience increased. When a best friend was present, there was less change in cortisol and global self-worth due to the negativity of the experience.     

Specificity of Reward Sensitivity and Parasympathetic-Based Regulation among Children with Attention-Deficit/Hyperactivity and Disruptive Behavior Disorders

Attention-deficit/hyperactivity disorder (ADHD) is associated with disruptionsin reward sensitivity and regulatory processes. However, it is unclear whether thesedisruptions are better explained by comorbid disruptive behavior disorder (DBD)symptomology. This study sought to examine this question using multiple levels ofanalysis (i.e., behavior, autonomic reactivity). One hundred seventeen children (aged 6 to 12 years; 72.6% male; 69 with ADHD) completed theBalloon-Analogue Risk Task (BART) to assess external reward sensitivity behaviorally.Sympathetic-based internal reward sensitivity and parasympathetic-based regulationwere indexed via cardiac pre-ejection period (PEP) and respiratory sinus arrhythmia(RSA), respectively. Children with ADHD exhibited reduced internal reward sensitivity (i.e.,lengthened PEP; F(1,112)=4.01, p=0.047) compared to healthy controls and werecharacterized by greater parasympathetic-based dysregulation (i.e., reduced RSAaugmentation F(1,112)=10.12, p=0.002). However, follow-up analyses indicated theADHD effect was better accounted for by comorbid DBD diagnoses; that is, childrenwith ADHD and comorbid ODD were characterized by reduced internal rewardsensitivity (i.e., lengthened PEP; t=2.47, p=0.046) and by parasympathetic-baseddysregulation (i.e., reduced RSA augmentation; t=3.51, p=0.002) in response to rewardwhen compared to typically developing youth. Furthermore, children with ADHD and comorbid CD exhibited greater behaviorally-based external reward sensitivity (i.e.,more total pops; F(3,110)= 5.96, p=0.001) compared to children with ADHD only (t=3.87, p=0.001) and children with ADHD and ODD (t=3.56, p=0.003). Results suggest that disruptions in sensitivity to reward may be betteraccounted for, in part, by comorbid DBD.Key Words: attention-deficit/hyperactivity disorder, autonomic nervous system,disruptive behavior disorders, reward sensitivityPowered     

Cortisol deviations in people with burnout before and after psychotherapy: a pilot study.

Burnout is characterized by exhaustion, cynicism, and feelings of reduced competence. These complaints may be reflected in disturbances in the main stress regulatory endocrine system: the hypothalamus pituitary adrenal (HPA) axis. In this study, the HPA-axis hormone cortisol was sampled after awakening and during the day in 22 participants with clinical burnout and in 21 healthy controls. The cortisol level after awakening was shown to be significantly lower in the burnout group as compared with the control group. Cortisol levels during the day did not differ. The same sampling procedure was repeated after 14 sessions of psychotherapeutic intervention. The intervention led to a significant reduction in complaints and to an increase of the initially lowered morning cortisol levels. No consistent correlations, however, between the changes in subjective complaints and the change in cortisol parameters were found.     

Emotional plasticity: conditions and effects of improving emotional competence in adulthood

This study aimed to investigate (a) whether it is possible to increase emotional competence (EC) in adulthood; (b) whether this improvement results in better mental, physical, and social adjustment; (c) whether this improvement can be maintained 1 year later; and (d) whether these benefits are accompanied by a reduction in stress-hormone secretion (i.e., cortisol). One hundred and thirty-two participants were randomly assigned to an EC-enhancing intervention (in group format) or to a control group. Participants in the intervention group underwent a specifically designed 15-hr intervention targeting the 5 core emotional competencies, complemented with a 4-week e-mail follow-up. Results reveal that the level of emotional competencies increased significantly in the intervention group in contrast with the control group. This increase resulted in lower cortisol secretion, enhanced subjective and physical well-being, as well as improved quality of social and marital relationships in the intervention group. No significant change occurred in the control group. Peer reports on EC and quality of relationships confirmed these results. These data suggest that emotional competencies can be improved, with effective benefits on personal and interpersonal functioning lasting for at least 1 year. The theoretical implications of these results as well as their practical implications for the construction and the development of effective emotional competencies interventions are discussed.