Acute Social Stress Research Articles

Acute social defeat stress upregulates gonadotrophin inhibitory hormone and its receptor but not corticotropin-releasing hormone and ACTH in the Male Nile Tilapia (Oreochromis niloticus)

Stress impairs the hypothalamic-pituitary-gonadal (HPG) axis, probably through its influence on the hypothalamic-pituitary-adrenal (= interrenals in the teleost, HPI) axis leading to reproductive failures. In this study, we investigated the response of hypothalamic neuropeptides, gonadotropin-inhibitory hormone (GnIH), a component of the HPG axis, and corticotropin-releasing hormone (CRH) a component of the HPI axis, to acute social defeat stress in the socially hierarchical male Nile tilapia (Oreochromis niloticus). Localization of GnIH cell bodies, GnIH neuronal processes, and numbers of GnIH cells in the brain during acute social defeat stress was studied using immunohistochemistry. Furthermore, mRNA levels of GnIH and CRH in the brain together with GnIH receptor, gpr147, and adrenocorticotropic hormone (ACTH) in the pituitary were quantified in control and socially defeated fish. Our results show, the number of GnIH-immunoreactive cell bodies and GnIH mRNA levels in the brain and the levels of gpr147 mRNA in the pituitary significantly increased in socially defeated fish. However, CRH and ACTH mRNA levels did not change during social defeat stress. Further, we found glucocorticoid type 2b receptor mRNA in laser captured immunostained GnIH cells. These results show that acute social defeat stress activates GnIH biosynthesis through glucocorticoid receptors type 2b signalling but does not change the CRH and ACTH mRNA expression in the tilapia, which could lead to temporary reproductive dysfunction.

Comparative Study of CRH Microinjections into PVN and CeA Nuclei on Food Intake, Ghrelin, Leptin, and Glucose Levels in Acute Stressed Rats

Introduction:Corticotropin-Releasing Hormone (CRH) is involved in stress and energy homeostasis. On the other hand, CRH receptors also exist within the paraventricular nucleus (PVN) and Central Amygdala (CeA) nuclei. The present study compared the effect of CRH microinjections into PVN and CeA on three consecutive hours and cumulative food intake, internal regulatory factors of food intake, such as serum leptin and ghrelin, as well as blood glucose levels in rats under different acute psychological (Social Stress [SS] and Isolation Stress [IS] group) stresses.Methods:Sixty-six male Wistar rats were randomly allocated to 11 groups: Control, Sham, CRH-PVN, CRH-CeA, SS, IS, SS-CRH-PVN, SS-CRH-CeA, IS-CRH-PVN, and IS-CRH-CeA groups. The CRH (2 µg/kg in 0.5 µL saline) was injected into PVN and CeA nuclei in rats under everyday, acute social stress and isolation stress conditions.Results:Acute isolation and social stresses did not affect cumulative food intake. Whereas isolation stress led to changes in both leptin and glucose levels, social stress reduced only glucose levels. Cumulative food intake significantly decreased under acute CRH injection into the CeA and particularly into the PVN. Blood glucose significantly reduced in all the groups receiving CRH into their CeA.Conclusion:The PVN played a more important role compared to CeA on food intake. These nuclei probably employ different mechanisms for their effects on food intake. Besides, it seems that exogenously CRH injection into the PVN probably had a more anorectic effect than naturally activated CRH by stresses. Acute isolation stress had a greater impact than social stress on leptin level and cumulative food intake. Thus, elevated food intake related to leptin compared to ghrelin and glucose levels in the CRH-PVN group under acute social stress.

Examining the role of ethnic microaggressions and ethnicity on cortisol responses to an acute stressor among young adults.

Objective: This study examined whether the frequency of experiences of ethnic microaggressions and the sensitivity to such experiences were associated with cortisol responses to an acute social stressor (Trier Social Stress Test; TSST) among an ethnically diverse sample of young adults (N = 109, Mage = 18.82 years, SD = 1.40 years, 74% female, 44% Latinx). Method: Self-reported experiences of and sensitivity to microaggressions were assessed using the Everyday Microaggressions Scale. Participants' salivary cortisol was collected before, immediately after, and at three 15-min intervals after the TSST (for a total of 5 salivary samples) to assess their cortisol responses to an acute social stressor. Results: Mixed model analyses revealed that experiencing a higher frequency of microaggressions (p = .005) and being more sensitive to those experiences (p = .001) were associated with a more blunted cortisol response (i.e., lower cortisol reactivity and recovery) to the TSST, relative to experiencing a lower frequency of microaggressions and being less sensitive to them. Furthermore, this blunted cortisol response to the TSST was more prominent among young adults of Latinx and other ethnic backgrounds (i.e., biracial, African American, and Native American) compared to their Asian American and non-Hispanic White peers (p = .034). Conclusion: Findings provide insight into the different ways in which experiences of ethnic microaggressions can be associated with biological markers of stress. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The Stressed Brain: Neural Underpinnings of Social Stress Processing in Humans.

As humans, we face a variety of social stressors on a regular basis. Given the established role of social stress in influencing physical and psychological functioning, researchers have focused immense efforts on understanding the psychological and physiological changes induced by exposure to acute social stressors. With the advancement of functional magnetic resonance imaging (fMRI), more recent work has sought to identify the neural correlates of processing acute social stress. In this review, we provide an overview of research on the neural underpinnings of social stress processing to date. Specifically, we summarize research that has examined the neural underpinnings of three types of social stressors commonly studied in the literature: social rejection, social evaluation, and racism-related stress. Within our discussion of each type of social stressor, we describe the methods used to induce stress, the brain regions commonly activated among studies investigating that type of stress, and recommendations for future work. This review of the current literature identifies activity in midline regions in both prefrontal and parietal cortices, as well as lateral prefrontal regions, as being associated with processing social rejection. Activity in the insula, thalamus, and inferior frontal gyrus is often found in studies using social evaluation tasks. Finally, racism-related stress is associated with activity in the ventrolateral prefrontal cortex and rostral anterior cingulate cortex. We conclude by taking a "30,000-foot view" of this area of research to provide suggestions for the future of research on the neuroscience of social stress.

Individual Differences in Cross-System Physiological Activity at Rest and in Response to Acute Social Stress.

Individual differences in long-term cardiovascular disease risk are related to physiological responses to psychological stress. However, little is known about specific physiological response profiles in young adults that may set the stage for long-term increased cardiovascular disease risk. We investigated individual differences in profiles of resting cardiovascular physiology and stress reactivity, combining parasympathetic, sympathetic, and hemodynamic measures. Participants (n = 744, 71% women, mean [standard deviation] age = 20.1 [2.4] years) underwent the Trier Social Stress Test, while blood pressure (systolic blood pressure, diastolic blood pressure), electrocardiograms (interbeat interval), and impedance cardiograms (preejection period, left ventricular ejection time) were recorded. Respiratory sinus arrhythmia was derived from the combination of the electrocardiogram and the impedance cardiogram. A three-step latent profile analysis (LPA) was performed on resting and reactivity values to derive clusters of individual physiological profiles. We also explored demographic and health behavioral correlates of the observed latent clusters. For resting physiology, LPA revealed five different resting physiology profiles, which were related to sex, usual physical activity levels, and body mass index. Five cardiovascular stress reactivity profiles were identified: a reciprocal/moderate stress response (Cr1; 29%), and clusters characterized by high blood pressure reactivity (Cr2: 22%), high vagal withdrawal (Cr3; 22%), autonomic coactivation (parasympathetic nervous system and sympathetic nervous system; Cr4; 13%), and overall high reactivity (Cr5; 12%). Men were more likely to belong to the high reactivity (Cr5) cluster, whereas women were more likely to have autonomic coactivation (Cr4). We identified five cardiovascular physiological reactivity profiles, with individuals displaying generalized hyperreactivity, predominant vagal withdrawal, autonomic coactivation, or blood pressure-specific hyperreactivity. Longitudinal studies are needed to determine whether these profiles are useful in early detection of individuals at high risk for cardiovascular disease.

Childhood Adversities and Salivary Cortisol Responses to the Trier Social Stress Test: A Systematic Review of Studies Using the Children Trauma Questionnaire (CTQ).

Alteration in cortisol response to acute social stressors has been hypothesized to mediate childhood adversities (CA) and increased morbidity in adulthood. However, the evidence supporting an association between CA and cortisol response to social stressors is inconclusive. The present review addressed this issue by reviewing the literature on CA and cortisol response to acute social stressors, with a focus on studies with adolescents or adults, using the Childhood Trauma Questionnaire (CTQ) to assess CA, and examining salivary cortisol response to the Trier Social Stress Test (TSST). Systematic searches of relevant articles in PsycINFO, PubMed, Web of Science and ScienceDirect in February and March 2020 identified 12 articles including 1196 participants with mean ages ranging from 15.3 to 52.3 yrs. across studies. CTQ scores were significantly associated with cortisol response in 2 studies. In addition, the physical abuse and emotional neglect subscales were associated with cortisol response respectively in 2 separate studies. The lack of association between CA and cortisol response calls for more longitudinal studies, and the use of formal records of maltreatment or informant reports in future research to complement information collected by retrospective measures. In addition, increased attention to biological mechanisms other than that associated with the regulation of cortisol in explaining the connection between CA and psychiatry morbidity is warranted.

Activity of a vmPFC-DRN Pathway Corresponds With Resistance to Acute Social Defeat Stress.

The ventromedial prefrontal cortex (vmPFC) plays a critical role in stress resilience through top-down inhibition of key stress-sensitive limbic and hindbrain structures, including the dorsal raphe nucleus (DRN). In a model of experience-dependent stress resistance, socially dominant Syrian hamsters display fewer signs of anxiety following acute social defeat when compared to subordinate or control counterparts. Further, dominants activate vmPFC neurons to a greater degree during stress than do subordinates and become stress-vulnerable following pharmacological inhibition of the vmPFC. Dominants also display fewer stress-activated DRN neurons than subordinates do, suggesting that dominance experience gates activation of vmPFC neurons that inhibit the DRN during social defeat stress. To test whether social dominance alters stress-induced activity of a vmPFC-DRN pathway, we injected a retrograde tracer, cholera toxin B (CTB), into the DRN of dominant, subordinate, and control hamsters and used a dual-label immunohistochemical approach to identify vmPFC neurons co-labeled with CTB and the defeat-induced expression of an immediate early gene, cFos. Results indicate that dominant hamsters display more cFos+ and dual-labeled cells in layers V/VI of infralimbic and prelimbic subregions of the vmPFC compared to other animals. Furthermore, vmPFC-DRN activation corresponded directly with proactive behavioral strategies during defeat, which is indicative of stress resilience. Together, results suggest that recruiting the vmPFC-DRN pathway during acute stress corresponds with resistance to the effects of social defeat in dominant hamsters. Overall, these findings indicate that a monosynaptic vmPFC-DRN pathway can be engaged in an experience-dependent manner, which has implications for behavioral interventions aimed at alleviating stress-related psychopathologies.

Sex differences in cortisol and memory following acute social stress in amnestic mild cognitive impairment

ABSTRACT Objective Older adults with amnestic mild cognitive impairment (aMCI) develop Alzheimer’s type dementia approximately 10 times faster annually than the normal population. Adrenal hormones are associated with aging and cognition. We investigated the relationship between acute stress, cortisol, and memory function in aMCI with an exploratory analysis of sex. Method Salivary cortisol was sampled diurnally and during two test sessions, one session with the Trier Social Stress Test (TSST), to explore differences in the relationship between cortisol and memory function in age-normal cognition (NA) and aMCI. Participants with aMCI (n = 6 women, 9 men; mean age = 75) or similarly aged NA (n = 9 women, 7 men, mean age = 75) were given tests of episodic, associative, and spatial working memory with a psychosocial stressor (TSST) in the second session. Results The aMCI group performed worse on the memory tests than NA as expected, and males with aMCI had elevated cortisol levels on test days. Immediate episodic memory was enhanced by social stress in NA but not in the aMCI group, indicating that stress-induced alterations in memory are different in individuals with aMCI. High cortisol was associated with impaired performance on episodic memory in aMCI males only. Cortisol in Session 1 moderated the relationship with spatial working memory, whereby higher cortisol was associated with worse performance in NA, but better spatial working memory in aMCI. In addition, effects of aMCI on perceived anxiety in response to stress exposure were moderated by stress-induced cortisol in a sex-specific manner. Conclusions We show effects of aMCI on Test Session cortisol levels and effects on perceived anxiety, and stress-induced impairments in memory in males with aMCI in our exploratory sample. Future studies should explore sex as a biological variable as our findings suggest that effects at the confluence of aMCI and stress can be obfuscated without sex as a consideration.

OXTR receptor (OXTR) gene rs53576 predicts proinflammatory C-reactive protein response to acute social stress in African American men

OXTR receptor (OXTR) gene rs53576 predicts proinflammatory C-reactive protein response to acute social stress in African American men

Salivary osteocalcin: Reactivity to acute social stress and relationships with concomitant stress biomarkers in healthy African Americans

High uric acid (UA) is associated with hypertension and cardiovascular disease (CVD), both of which occur disproportionately among African Americans. High UA also predicts greater blood pressure reactivity responses to acute social stress. However, whether UA itself shows reactivity in response to stress is unknown. We evaluated salivary uric acid (sUA) and blood pressure reactivity in response to acute social stress. Healthy African Americans (N = 103; 32 % male; M age = 31.36 years), completed the Trier Social Stress Test. sUA and blood pressure measurements were taken before, during and after the stressor task. sUA showed significant reactivity and recovery, especially among older African Americans. Total sUA activation was also associated with systolic and diastolic blood pressure total activation. Findings illuminate that acute stress may be a way in which UA is implicated in hypertension and CVD, suggesting a critical need to explore UA reactivity as a novel parameter of the acute stress response.

GSB-106 Dipeptide Mimetic of Brain-Derived Neurotrophic Factor Prevents Anhedonia Development under Acute Social Defeat Stress Conditions in Mice

The influence of the dimeric dipeptide mimetic of brain-derived neurotrophic factor (BDNF) bis(N-monosuccinyl-L-seryl-L-lysine) hexamethylenediamide (GSB-106, dosage form) during three-day peroral administration at a dose of 0.1 mg/kg on the 1% sucrose solution preference test and the content of postsynaptic density protein (PSD-95) in the prefrontal cortex and hippocampus of C57Bl/6 mice was studied in an acute three-day social defeat stress model. The preference for sucrose solution decreased and the PSD-95 content in the prefrontal cortex was halved statistically significantly in stressed mice as compared to control animals. The hippocampal PSD-95 content in stressed animals did not change. Anhedonia was completely prevented after each stress session according to the sucrose preference test with peroral administration of GSB-106 at a dose of 0.1 mg/kg once per day for three days. GSB-106 did not reduce the prefrontal PSD-95 content of stressed animals during the experiment.

Evaluación e Intervención Psicofisiológica Térmica de Sesión Única de Estrés Social en Estudiantes de Psicología

El estrés social agudo induce un incremento de la actividad simpática, mientras que la relajación promueve actividad parasimpática. Sin embargo, algunas personas no logran regular su balance autonómico (estrés- relajación), por lo que se propuso evaluar el efecto de una intervención psicofisiológica de sesión única. Participaron estudiantes de Psicología (n= 15) quienes completaron una evaluación psicométrica de medidas de distrés (ansiedad, depresión, estrés postraumático, alexitimia y percepción subjetiva de estrés). Posteriormente se aplicó el Trier Social Stress Test (TSST-Cog), un protocolo conductual para inducir estrés social agudo, seguido de una estrategia de relajación por imaginería guiada (IG). Mediante un diseño de medidas repetidas se registró su temperatura nasal y se comparó la diferencia térmica entre estrés y relajación. Posteriormente, los estudiantes que reportaron un nivel de distrés en las medidas psicométricas se aleatorizaron en dos subgrupos para aplicar un procedimiento de condicionamiento térmico en manos – relajación y un grupo control. Los resultados revelaron una asociación (p< 0.05) entre la temperatura nasal y las medidas de distrés; un decremento de la temperatura nasal post-TSST-Cog (acompañado de un aumento de percepción de estrés) y un incremento térmico (asociado a una disminución de estrés) post-IG existiendo una diferencia estadística entre ambos procedimientos (p< 0.01). Para los participantes con distrés, el procedimiento de condicionamiento térmico logró revertir el descenso de temperatura (p= 0.05), mientras que los estudiantes sin el procedimiento no hubo cambios post-IG (p= 0.15). Se concluye que el uso del protocolo TSST-Relajación puede ser utilizado como un procedimiento diagnóstico del funcionamiento emocional, así como la promoción del condicionamiento térmico en quienes no se beneficien de los procedimientos de relajación tradicionales.

Autonomic nervous system activity predicts increasing serum cytokines in children

Systemic inflammation is associated with increased risk for prevalent and costly diseases, and animal models implicate the autonomic nervous system in the control of inflammatory processes. In humans, research on autonomic-immune connections has been much more limited, and has focused on single branch autonomic measures (i.e., either parasympathetic or sympathetic). The current study utilized cardiac autonomic balance (CAB), derived from dual-branch cardiac autonomic recordings, to test the relation between resting autonomic function and inflammatory reactivity to challenge in children. MethodsParticipants included 96 children (51 boys, 45 girls) ages 9–11 years (mean age = 9.93 years, SD = 0.57 years). CAB values were calculated from standardized measures of parasympathetic and sympathetic activity, namely resting respiratory sinus arrhythmia and pre-ejection period data, respectively. Children provided two blood samples, one before and one following exposure to an acute social stressor or control condition. Serum was assayed for four cytokines that orchestrate inflammation: interleukin-6 (IL6), interleukin-8 (IL8), interleukin-10 (IL10), and tumor necrosis factor-alpha (TNFa). ResultsWe discovered large individual differences in inflammatory marker production across children, and no average main effect of stress condition. CAB significantly predicted these individual differences, such that children lower on CAB showed increasing serum cytokines from time 1 to time 2. In contrast, children with greater CAB tended to show declining inflammatory markers across the session. DiscussionLow cardiac autonomic balance (i.e., the combination of low parasympathetic and high sympathetic activity) may be a useful marker of proinflammatory tendencies in children, suggesting novel paths for early risk detection and intervention.

Physiological stressor impact on peripheral facial temperature, Il-6 and mean arterial pressure, in young people.

Nowadays, stress is part of everyday life, whose long-term effects can trigger health risks. Among the main alterations that occur in the human body we can find the variation of inflammatory activity, blood pressure, and facial peripheral temperature. The objective of this work is to show the facial thermal behavior for men and women, as well as the differences in vascular and inflammatory responses induced by the effect of acute social stress. The Trier Social Stress Test was applied to 15 women and 15 men, free of disease, with an average age of 23.8 years and a standard deviation of 5.52. After capturing the baseline state, and at the end of the test, the inflammatory activity was measured through salivary interleukin-6; the mean blood pressure, and the capture of facial thermographic images. For the thermal images, six regions of interest (biothermomarkers) were analyzed: forehead, right cheek, left cheek, chin, nose, and corrugator muscle. The results obtained after analyzing the information were: an increase in inflammatory activity, an increase in mean blood pressure, and significant temperature changes in different areas of interest of the face, depending on gender. For men, it only appeared in the region of the nose and women's forehead, cheeks, and nose. Furthermore, the correlation between the three variables (il-6, blood pressure, and temperature) was performed and no significant values were found. Regarding the relationship between genders, only significant values were found for il-6.

LRRK2 mutation alters behavioral, synaptic, and nonsynaptic adaptations to acute social stress.

Parkinson's disease (PD) risk is increased by stress and certain gene mutations, including the most prevalent PD-linked mutation LRRK2-G2019S. Both PD and stress increase risk for psychiatric symptoms, yet it is unclear how PD-risk genes alter neural circuitry in response to stress that may promote psychopathology. Here we show significant differences between adult G2019S knockin and wild-type (wt) mice in stress-induced behaviors, with an unexpected uncoupling of depression-like and hedonia-like responses in G2019S mice. Moreover, mutant spiny projection neurons in nucleus accumbens (NAc) lack an adaptive, stress-induced change in excitability displayed by wt neurons, and instead show stress-induced changes in synaptic properties that wt neurons lack. Some synaptic alterations in NAc are already evident early in postnatal life. Thus G2019S alters the magnitude and direction of behavioral responses to stress that may reflect unique modifications of adaptive plasticity in cells and circuits implicated in psychopathology in humans.NEW & NOTEWORTHY Depression is associated with Parkinson's disease (PD), and environmental stress is a risk factor for both. We investigated how LRRK2-G2019S PD mutation affects depression-like behaviors, synaptic function, and intrinsic neuronal excitability following stress. In response to stress, the mutation drives abnormal synaptic changes, prevents adaptive changes in intrinsic excitability, and leads to aberrant behaviors, thus defining new ways in which PD mutations derail adaptive plasticity in response to stress that may contribute to disease onset.

Hippocampal-Amygdala Resting State Functional Connectivity Serves as Resilience Factor for Short- and Long-Term Stress Exposure

Stressful experiences modulate neuro-circuitry function, and the temporal trajectory of these alterations, elapsing from early disturbances to late recovery, heavily influences resilience for psychopathology. In our previous work, we found that sustainability of subjective stress feeling following an acute social stressor, corresponded to neural stress response as indicated by resting-state functional connectivity (rsFC). In particular, we found that sustained enhancement of amygdala-hippocampus rsFC, for as long as 2 hours following lab stress induction, anti-correlated with faster recovery in stress feelings (Vaisvaser et al., 2013, 2016). Nevertheless, it is yet unknown if such acute rsFC changes could also mark long-term recovery from traumatic life stress.

Emotion expressivity in the Dutch: Validation of the Dutch translation of the Berkeley Expressivity Questionnaire.

When examining emotions and emotion regulation, we discriminate between emotion experience and emotion expressivity. Research shows that the two are modestly related. The Berkeley Expressivity Questionnaire (BEQ) was designed to assess positive and negative expressivity, as well as the intensity of the expressive behavior. The current article reports on 2 studies that examined the reliability and validity of the Dutch translation of the BEQ. In Study 1, we performed a confirmatory factor analysis of the BEQ items in two samples that differed in age (young adults and adults), correlated the facet and total scores with measures of behavioral control, affective response tendencies, and emotion regulation strategies, and examined sex differences. Results confirmed the three-factor structure and further showed that factors were correlated, and two items loaded on all factors. Internal consistency was good, and test-retest reliability was excellent. As expected, emotion expression was larger in women. Convergent and divergent validity were confirmed. Behavioral control measures were inversely related to emotion expression. Although neuroticism and depression were associated with negative expressivity, extraversion, openness, and agreeableness were associated with positive expressivity. Emotion regulation strategies generally showed association patterns in the expected directions. In Study 2, we report on the predictive value of the BEQ facet scores for the emotional response to acute social evaluative stress. Results showed that only expression intensity was significantly associated with a larger emotional stress response. In conclusion, the Dutch version of Berkeley Expressivity Questionnaire is a reliable and valid instrument to be used in the Dutch setting. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Chemogenetic activation of an infralimbic cortex to basolateral amygdala projection promotes resistance to acute social defeat stress

Tremendous individual differences exist in stress responsivity and social defeat stress is a key approach for identifying cellular mechanisms of stress susceptibility and resilience. Syrian hamsters show reliable territorial aggression, but after social defeat they exhibit a conditioned defeat (CD) response characterized by increased submission and an absence of aggression in future social interactions. Hamsters that achieve social dominance prior to social defeat exhibit greater defeat-induced neural activity in infralimbic (IL) cortex neurons that project to the basolateral amygdala (BLA) and reduced CD response compared to subordinate hamsters. Here, we hypothesize that chemogenetic activation of an IL-to-BLA neural projection during acute social defeat will reduce the CD response in subordinate hamsters and thereby produce dominant-like behavior. We confirmed that clozapine-N-oxide (CNO) itself did not alter the CD response and validated a dual-virus, Cre-dependent, chemogenetic approach by showing that CNO treatment increased c-Fos expression in the IL and decreased it in the BLA. We found that CNO treatment during social defeat reduced the acquisition of CD in subordinate, but not dominant, hamsters. This project extends our understanding of the neural circuits underlying resistance to acute social stress, which is an important step toward delineating circuit-based approaches for the treatment of stress-related psychopathologies.

Efectos diferenciales de la citoquina IL-6 después del estrés social agudo: resultados preliminares

Objetivo: evaluar el efecto diferencial del estrés social agudo sobre la interleucina 6 salival mediante la prueba conductual Trier Social Stress Test (TSST).Método: participaron diecisiete estudiantes universitarios, normotensos, a quienes se registró la presión arterial media en tres momentos: 10 minutos antes, pre y post TSST. También se recolectó una muestra de IL-6 salival pre-post TSST.Resultados: hubo un incremento en la presión arterial media sólo cuando se presentó el TSST (p<0.001). El nivel de IL-6 pre-post tsst no mostró cambios estadísticamente significativos (p>0.05). El análisis de IL-6 reveló que 53 % de la muestra incrementó su concentración de IL-6 (p<0.001) mientras que 47 % de los participantes decrementó su nivel de IL-6 (p<0.01), existiendo una diferencia estadísticamente significativa post-TSST entre ambos subgrupos (p<0.05).Limitaciones: se recomienda establecer parámetros normativos de la IL-6 salival.Principales hallazgos: los datos preliminares que presentamos sugieren que el estrés social agudo incrementa la presión arterial, pero que este efecto induce una expresión diferencial de IL-6 en todos los participantes, en aquellos con una concentración baja de IL-6 se incrementa después del estrés agudo, mientras que aquellos con un nivel alto de IL-6 previo, la prueba tiende a disminuirla.

C-reactive protein in saliva and dried blood spot as markers of stress reactivity in healthy African-Americans.

Aim: Noninvasive assessments of C-reactive protein (CRP) in stress contexts have seldom been compared. This study evaluated CRP response to acute social stress as measured in saliva and dried blood spot (DBS). Materials & methods: African-Americans (N=118; mean age=32years) participated in a laboratory-based social-evaluative stressor task. Six saliva samples taken before, during and after were assayed for salivary CRP. DBS measurements of CRP were taken alongside saliva at the first and last collection. Results: Salivary and DBS CRP were modestly positively associated with one another at baseline, and only salivary CRP increased in response to the stressor task. Conclusion: Noninvasive measures of CRP reactivity may be only moderately related to one another in stress reactivity contexts.