НАУЧНО-МЕТОДИЧЕСКИЕ АСПЕКТЫ ОЦЕНКИ ЭФФЕКТИВНОСТИ НАПИТКА «СИЛА ПРИРОДЫ»

In the present study, we investigated the acute effects of 2 different kinds of stress, namely physical stress (foot shock) and psychological stress (non-foot shock) induced by the communication box method, on the sleep patterns of rats. The sleep patterns were recorded for 6 h immediately after 1 h of stress. Physical and psychological stress had almost opposite effects on the sleep patterns: In the physical stress group, hourly total rapid eye movement (REM) sleep and total non-REM sleep were significantly inhibited, whereas psychological stress enhanced hourly total REM sleep but not total non-REM sleep. Further results showed that total REM sleep, total non-REM sleep, total sleep and the total number of REM sleep episodes in 5 h were reduced, and that sleep latency was prolonged compared to the control group. On the other hand, in the psychological stress group, the total REM sleep in 5 h was increased significantly due to the prolongation of the average duration of REM sleep episodes and reduced REM sleep latency. In addition, the plasma of corticosterone increased significantly after physical stress but not after psychological stress. These results suggested that the sleep patterns, particularly the patterns of REM sleep following physical and psychological stress, are probably regulated by 2 different pathways.

Multiple adult health problems are associated with adolescent stress. As the brain discriminates physical and psychological stressors by activation of different neural networks, we hypothesized that behavioral and physiological performance would be modulated differently based on the nature of the stressors. Thus, we studied the comparative effects of adolescent repeated physical and psychological stresses on adult cognitive performance, pro-oxidant-antioxidant balance (PAB) and heart rate in female rats. The aim was to differentiate disparate potency of chronic psychological and physical stresses leading to long-term behavioral and physiological alterations. Twenty-one female rats were divided randomly into three groups of seven rats each; control, physical, and psychological stress. Experimental rats were exposed to the stressors for five consecutive days (10 min daily) via a two-communication box. After verifying stress induction by serum corticosterone measurement, the rats were returned to their home cage for 6 weeks, until adulthood, elevated plus maze (EPM), forced swimming test (FST), Y-maze, object recognition task (ORT), and passive avoidance test (PAT) were used as five different behavioral tests to evaluate cognitive performance of each group. Serum PAB and heart rate were measured to assess long-term stress-induced physiological disorders. The results showed exposure to adolescent psychological stress resulted in a larger set of significant changes (in behavioral variation, oxidative stress, and elevated heart rate) 6 weeks post-stress compared to adolescent physical stress. Hence, mental health care in adolescence and therapies targeting PAB and heart rate could be prevention and treatment approaches to confront persistent adolescent stress-induced disorders.Lay summaryThe aim of our study on female laboratory rats was to differentiate disparate potency of chronic psychological and physical stresses in adolescence leading to long-term behavioral and physiological alterations. The results suggest that psychological stresses result in a greater extent of changes compared to physical stress. Adolescent chronic psychological stress may reveal itself in the form of certain behavioral and physiological variations in adulthood. Therefore, mental health care in adolescence could be a valuable prevention approach to confront a variety of adult stress-induced disorders.

Psychological stress is associated with the pathogenesis of several neuropsychiatric disorders. In contrast, physical stress, as provoked by exercise, counteracts symptoms and potentially also disease progression. The kynurenine pathway, which is imbalanced in neuropsychiatric disorders, responds to both psychological and physical stress. Here, we compared the acute effects of psychological versus physical stress on the kynurenine pathway and inflammatory mediators. Thirty-five healthy males (mean age: 24.09±3.39 years) underwent both the Trier Social Stress Test (psychological stressor) and the Wingate-Test (physical stressor). The kinetics of tryptophan and its metabolites as well as cytokines IL-6, IFN-γ, TNF-α, and IL-10 were measured before and after the two stress conditions. After both stressors, there was a significant change over time for the kinetics of tryptophan metabolites and for cytokines. Furthermore, the reactivity of kynurenine pathway metabolite ratios and cytokines was statistically greater after physical stress than after psychological stress. The increased metabolic flux towards kynurenic acid following acute physical stress suggests an exercise-induced neuroprotective mechanism. Despite the paradoxical influence of both stressors on neuropsychiatric diseases, the acute kynurenine pathway reactivity appears to be similar, although effects were more pronounced in response to physical stress.

Physical and emotional stress have differential effects on preference for saccharine and open field behaviour in rats

ObjectiveThis study examined a novel method to differentiate between mental and physical stress using Baevsky's Enhanced Stress Technique.BackgroundOccupational stress events, whether mental or physical, are handled by the sympathetic and parasympathetic nervous systems, which have been shown to be associated with heart rate variability (HRV), but have not been previously differentiated.MethodNaturalistic HRV and accelerometer data were measured continuously using wrist-worn sensors during a typical 12-h direct-care nursing shift (28 ICU nurses). Physical and mental stress events were calculated using the Baevsky's Stress Index, and Activity Index was used to investigate their differences between mental and combined mental and physical stress.ResultsRoot mean square of successive differences between heartbeats (RMSSD), which is associated with the parasympathetic nervous system activity as well as low-frequency power/high-frequency power (LF/HF ratio), and the alpha value of detrended fluctuation analysis (DFA a2), which are associated with the balance between sympathetic and parasympathetic nervous system activity, were the most predictive features of stress events (accounting for AUC of 85.46).ConclusionBaevsky's Enhanced Stress Technique shows promise in assessing occupational mental stress among ICU nurses. There were more persistent and significant physiological changes in HRV associated with combined mental and physical stress events.ApplicationFindings suggest a new stress measurement method for classifying occupational mental stress. Measurement using wrist-worn accelerometer and HRV data sources has pragmatic relevance to the design of real-time, noninvasive, and cost-efficient stress monitoring tools relevant to applications in high-stress work environments.

Prenatal psychological stress causes higher emotionality, depression-like behavior, and elevated activity in the hypothalamo-pituitary-adrenal axis

Young women post-MI have higher plasma concentrations of interleukin-6 before and after stress testing

Psychological and physical stress induce differential effects on human colonic motility

Acute stress exposure can elicit analgesic responses in multiple pain models. Research indicates that dopaminergic pathways in the hippocampus contribute to the analgesic responses elicited by forced swim stress, considered a combination of physical and psychological stress. Since psychological and physical stresses can trigger different brain pathways and areas, this study has examined how dopaminergic receptors in the CA1 region of the hippocampus affect the pain relief induced by restraint stress (RS), generally considered a psychological stress, in an acute pain model. Ninety-six Wistar rats underwent stereotaxic surgery, during which a cannula was unilaterally implanted in the CA1 region of the hippocampus. Five minutes prior to exposure to RS, D1- and D2-like dopamine receptor antagonists (SCH23390 and sulpiride, respectively) or their respective carriers, saline and DMSO, were administered in different doses (0.25, 1, and 4 µg/0.5 µl per rat) into the CA1 area. The analgesic effects of RS were examined with and without dopaminergic receptor antagonists using the tail-flick test. This study's findings indicated that the administration of SCH23390 and sulpiride into the CA1 area of the hippocampus at the maximal doses (4 µg/0.5 µl; P < 0.001) markedly diminished the analgesic benefits of RS in the acute pain paradigm. The magnitude of estimated ED50s in the effect of these antagonists on reducing the RS-induced analgesia was 1.64 µg for SCH23390 and 2.79 µg for sulpiride, suggesting that both dopamine D1-like and D2-like receptors in the CA1 region of the hippocampus likely contribute to the analgesic effects of RS in the rats.

Despite accumulating evidence that psychological stress has a short-lasting detrimental effect on asthma, little is known about the way stress in childhood predisposes to adult asthma. Using a communication box, we investigated the long-lasting effect of early psychological and physical stress on adult asthma in mice. Male BALB/c mice were exposed to either psychological stress or physical stress three times (every other day) during their fourth week of life. The mice were sensitized to ovalbumin at 8 and 10 weeks, and an ovalbumin airway challenge was conducted at the age of 11 weeks. Twenty-four hours after ovalbumin challenge, both psychological and physical stress-exposed mice exhibited a significant acceleration in the number of total mononuclear cells and eosinophils and airway hyperresponsiveness compared with control mice. No differences in serum anti-OVA-specific immunoglobulin E levels were found between stress-exposed and control animals after antigen sensitization. In the psychological stress group, but not in the physical stress group, an elevation of the serum corticosterone levels during ovalbumin challenge was significantly attenuated in comparison with the control group. Moreover, pretreatment with RU-486, a glucocorticoid receptor antagonist, before ovalbumin challenge completely inhibited a psychological stress-induced exacerbation of asthma. However, pretreatment with GR-82334, a neurokinin-1 receptor antagonist, failed to affect physical stress-induced augmentation of airway inflammation. Early psychological and physical stresses aggravated adult asthma via hyporesponsiveness of the hypothalamic-pituitary-adrenal axis during antigen challenge and via a pathway(s) distinct from the hypothalamic-pituitary-adrenal axis or neurokinin-1 receptors.

Sulpiride Specifically Attenuates Psychological Stress-Induced Gastric Lesions in Rodents

Endocrine and cardiovascular responses to a series of graded physical and psychological stress stimuli in healthy volunteers.

It has been known that CA change during physical exercises and associate with dynamic aspects of the coagulation fibrinolysis system of the blood. Therefore, we studied fibrin and fibrinogen degradation products (FDP) under physical exercises together with LDH, CPK, LA, CRE, Na, K and P. 1) College students of Department of Education majoring in sciences of physical education significantly increased activities of CPK and LDH during the training for volleyball games compared with the pre-training values. This increment was remarkable for those who exercised hard, that is, who were loaded with large physical stress. 2) Changes in LA were included in the range of its normal values. Freshmen who had not been trained much and consequently whose adaptability for physical stress was insufficient increased the LA level significantly relative to the pre-training level. 3) Although changes in P were included in the range of its normal values, significant increase was observed by physical stress. Examinations by individual disclosed that a tendency of changes in P was similar to that in CPK and FDP. 4) The tendency of changes in FDP agreed with that in CPK and P and an increase was observed for those who were loaded with large physical stress. It was further observed that especially for those who were loaded with large mental stress together with physical stress the increase in FDP was evident. Therefore, it has been suggested that FDP can be used as an index of biotic effects of not only physical stress but also mental stress.

Re-defining Sustainability: Living in Harmony with Life on Earth

Mental sweating is human sweating that is accelerated via the sympathetic nerve by application of mental or physical stress. In the neurosciences, there is keen interest in this type of sweating, because the amount of sweat in response to a stress applied to a volunteer directly reflects activity of the sympathetic nerve. It is therefore of particular value that optical coherence tomography (OCT) can provide clear in vivo imaging of the spiral lumen of an eccrin sweat gland in the epidermis with a spatial resolution around 10 mum. We demonstrate dynamic OCT of mental sweating of an eccrin sweat gland on a human fingertip, where the sweating dynamics can be tracked by time-sequential OCT images with a frame spacing of one second. An instantaneous amount of sweat stored in the spiral lumen is evaluated quantitatively in each OCT image, resulting in time variation measurements of excess sweat in response to mental or physical stress. In the dynamic OCT of mental sweating, as demonstrated here, we note for the first time internal sweating without ejection of excess sweat from the spiral lumen to the skin surface. Internal sweating has not been previously detected without the availability of our dynamic OCT technique. Until now, it has been commonly accepted that sweating is always accompanied with ejection of excess sweat to the skin surface. On the basis of our findings reported here, this type of sweating should now be referred to as external sweating. In this study, we demonstrate that internal sweating occurs more often in the case where mental stress is applied to a volunteer, and that it is more useful for evaluation of activity of the sympathetic nerve. The dynamic OCT for both external and internal sweating is demonstrated.