Bone marrow hemopoiesis at emotional stress reactions of various intensity upon a background of exposure to low dose ionizing radiation

Rats preliminary exposed to 0.9 Gy of ionizing radiation showed disturbances in the development of adaptive reactions of blood system to emotional stress, compensatory capacity of the blood system being decreased. A degree of the disturbances directly depended on the duration and intensity of the emotional stress: at the prolonged intensive emotional stress a sharp decrease in the adaptive and compensatory capacity of blood system was found; at short intensive or moderate stress the changes in the adaptive and compensatory capacity of hemopoiesis were less pronounced. A combined action of low-dose ionizing radiation and short weak emotional stress did non affect the adaptive and compensatory capacity of hemopoietic system.     

Effect of mexidol on hemopoietic system in conditions of an emotional stress after exposure to ionizing radiation

The emotional stress after an irradiation can complicate the current of radiative defeats. At an emotional stress developing in early terms after an irradiation in low doses, are reduced adaptive and compensator capabilities of hemopoietic system. The emotional stress after a lethal dose irradiation inhibits the post-radiation recovery of haemopoiesis, aggravates the course of acute radiation disease and decreases the efficiency of the radioprotector--indralin. These disorders are especially pronounced under a prolonged and intensive stress. The use of the mexidol, having anxiolytic and antistress by activity, made it possible to arrest completely disturbances in the development of adaptive reactions to stress in the blood system and to normalize its compensatory potentialities in animals under conditions of combined influence of intensive long-term emotional stress and of low-dose irradiation. In the case of lethally irraiated animals, the treatment of stressed animals with mexidol favorably influenced the course of acute radiation disease, enhanced recovery processes in the blood system. Under these conditions, the use of mexidol completely removes the negative effect of emotional stress in indralin-protected animals. The pharmacological correction by mexidol from displays of an intensive emotional stress, developing after an irradiation in various doses, can be a part in system of medical measures.     

Comparative analysis of the stability of cardiovascular system functions in immobilized rats of different strains

The dynamics of arterial pressure and heart rate was studied in rats of different genetic lines (non-linear, Wistar, Way and August) during immobilization emotional stress. Different lines were characterised by different stability and ability of adaptation to emotional stress. Prognostic criteria were specified that enable to foresee at an early stage of emotional stress the disturbances of cardio-vascular control. The conclusion is made that resistancy against cardio-vascular disturbances during emotional stress is of genetic nature as well as may be due to characteristics of individual growth.     

Role of the GABAergic system in the mechanism of the stress-regulating action of phenibut

Disturbances in GABA-ergic inhibitory system were noted upon the exposure of thalamus and hypothalamus of experimental animals to stress of 18 hours and longer duration but not of 3 hours duration. Phenibut (I mg/kg) eliminates the symptoms of GABA-system disturbances revealed upon exposure to stress, decreases the tension of stress reaction and hyperglucocorticoidemia which causes hyperglycemia. In the bodies of intact rats phenibut causes "switching on" of adaptive GABA-system function, which is more physiological than the one appearing on short-term stress.     

Light optical and electron microscopic study of the nodose ganglion neurons in emotional stress

Cell bodies of cardiovascular receptors localized in the ganglion nodosum of rabbits exposed to experimental emotional stress were studied with the light and electron microscope. Two groups of animals were selected for investigation. Under emotional stress rabbits of one group demonstrated almost unchanged arterial pressure and only a small increase in heart rate, while animals of the other group displayed strongly marked disturbances of their blood circulation leading to the lethal outcome at the end of experiment. In the first group rabbits, the microscopic anatomy and ultrastructure of the nodose ganglion neurons indicated an increased activity in the nerve cell. At the same time, morphological evidences of exhaustion were revealed in neurons of the nodose ganglion of the second group rabbits. A possible role of the distortion of the afferent information in pathogenesis of cardiovascular disorders under emotional stress is discussed.     

A tryptic hydrolysate from bovine milk alphaS1-casein improves sleep in rats subjected to chronic mild stress

The putative effects of a tryptic bovine alphaS1-casein hydrolysate on stress-induced sleep disorders were investigated and their possible link with typical blood stress parameters such as plasma corticosterone concentrations and glycaemia was assessed. Rats were subjected to chronic stress in the form of environmental disturbances, while receiving an oral administration of the alphaS1-casein hydrolysate (CH). Chronic stress significantly reduced sleep duration in control rats during the first 2 days of the stress period, but stress-induced sleep disturbance was prevented in CH-treated rats. Indeed, CH administration allowed the maintenance of slow wave sleep (SWS) duration and even a slight increase in paradoxical sleep (PS) duration in treated rats. Results on plasma corticosterone concentrations and on glycemia values were inconclusive with respect to the implication of the HPA axis in this study. However, the protective effect of the alphaS1-casein hydrolysate on sleep during exposure to our chronic mild stress conditions may be mediated by modulation of the central adrenergic response.     

Role of emotional stress in disorders of carbohydrate tolerance

Two series of rabbit experiments were carried out to study the influence of emotional stress on glucose tolerance. Relatively short-term (10 days) chronic emotional stress induced by prolonged (2 h daily) intermittent stimulation of negative emotiogenic zones of the hypothalamus through implanted electrodes led to decreased glucose tolerance. Repeated powerful emotional stresses induced by the clash of food and pain irritation did not pass traceless and manifested in the same glucose tolerance disturbances after a lengthy period of time (1 year).     

Obesity and sleep disturbances: meaningful sub-typing of obesity

Obesity, excessive daytime sleepiness (EDS), and self-reported short sleep duration appear to be on the rise, while there is evidence that obesity and these sleep disorders are strongly connected. In this paper, we review data that challenge the common belief that the sleep apnoea and sleep loss, frequently associated with obesity, are the primary determinants of obesity-related objective daytime sleepiness and subjective fatigue (tiredness without increased sleep propensity). Specifically, obesity is associated with objective and subjective EDS regardless of the presence of sleep apnoea. The association between obesity and EDS was confirmed in recent studies of large random samples of the general population or clinical samples, which showed that the primary determinants of subjective EDS were depression, metabolic disturbances, i.e. obesity/diabetes and insulin resistance, and lack of physical activity, and, secondarily, sleep apnoea or sleep loss. Paradoxically, within the obese, with or without sleep apnoea, those who slept objectively better at night are sleepier (objectively) during the day than those who slept worse. The distinguishing factor between those that slept better vs. those that slept worse appears to be level of emotional stress. Furthermore, many studies reported that obesity is associated with self-reported short sleep duration; however, it appears that short sleep duration is a marker of emotional stress rather than a reflection of true sleep loss. Based on these data, we propose that obesity-related deeper sleep and objective EDS are primarily related to metabolic disturbances, whereas obesity-related poorer sleep and subjective fatigue appear to be the result of psychological distress. Furthermore, based on data from studies in normal controls and patients with sleep disorders, it appears that the interaction of the hypothalamic-pituitary-adrenal (HPA) axis and pro-inflammatory cytokines determines the level of sleep/arousal within the 24-hour cycle, i.e. "eucortisolemia" or "hypocortisolemia" plus hypercytokinemia is associated with high sleep efficiency and objective sleepiness, whereas "hypercortisolemia" plus hypercytokinemia is associated with low sleep efficiency and fatigue. In conclusion, we propose that the above-reviewed data provide the basis for a meaningful phenotypic and pathophysiologic sub-typing of obesity. One subtype is associated with emotional distress, poor sleep, fatigue, HPA axis "hyperactivity," and hypercytokinemia while the other is associated with non-distress, better sleep but more sleepiness, HPA axis "normo or hypoactivity," and hypercytokinemia. This proposed sub-typing may lead to novel, preventive and therapeutic strategies for obesity and its associated sleep disturbances.     

The adaptive reactions in hemopoietic system of the irradiated mice of two lines, differing in the level of emotionally-stress reactions on the emotional stress

On lines of the mice genetically differing on the sensitivity on emotional stress (steady--of the mouse of the line C57BL/6 or sensitive--of the mouse of the line BALB/c), the research of the development of the adaptive reactions in the system of the blood on the emotional stress influencing animals on the background of the preliminary irradiation in a low dose (0.9 Gy) is carried out. The unirradiated mice of the line C57BL/6 adequately reacted on the stress, that was shown in a moderate behavioural reaction during the period of stress, and the development of high-grade adaptive reactions in the hemopoietic system. Among the mice of the line C57BL/6 in conditions of the combined influence of ionizing radiation and of the emotional stress was not revealed of the infringements of the adaptive reactions of the hemogenesis. As opposed to these data, among unirradiated mice of the line BALB/c the sharply expressed behavioural reactions during the stress were marked, that was accompanied by incomplete development of the adaptive reactions in the system of a blood on the stress. Under the influence of stress on the previously irradiated animal line BALB/c was observed the inhibition of the medullar hemopoiesis.     

Role of brain noradrenergic mechanisms in disturbing the circadian rhythm of the functioning hypothalamo-hypophyseo-adrenal cortex system in white rats in early ontogeny

The effects of hormone action and disturbance in catecholamine synthesis in the early postnatal ontogenesis on the circadian rhythm in the hypothalamic-hypophysial-adrenocortical system function were compared in the adult albino rat males. Injection of prednisolone on the 17-19th days of life blocked completely the diurnal rhythm of the corticosterone basal level in blood, the rhythm of adrenocortical response to an emotional stressor and to injection of noradrenaline into the brain lateral ventricle in 3-4 month old animals. Injection of an inhibitor of tyrosine hydroxylase, alpha-methyl-p-tyrosine, at the same period resulted in disappearance of the diurnal rhythm of the corticosterone basal level in adult animals, although the rhythm of response to an emotional stressor or injection of noradrenaline into the brain remained unchanged. A conclusion has been reached that disturbances in catecholamine synthesis in the early postnatal period induces long-term changes of predominantly tonic corticosterone secretion, while the hormone action on the circadian rhythm of the corticosterone basal level and stress response is only partly due to changes in noradrenergic regulation of the hypothalamic-hypophysial-adrenocortical system.     

The luminescence of blood leukocytes, stained with the fluorochrome acridine orange, from surgical patients in the dynamics of emotional, anesthesiological and surgical stress

Luminescence of blood leukocytes of surgical patients during treatment was studied using orange acridine. Luminescence intensity at 640 nm wave length (I640) was the most informative. It characterized amount of single-stranded nucleic acids, synthesized in cell due to previous activation of protein-synthesizing system and hence cell functional activity, while in lymphocytes these changes exceeded by duration and amplitude those in neutrophils. During premedication (emotional stress) I640 was minimal, during anesthetization it developed, and sharply raised during traumatic period of surgery and after it, as reflection of immune system participation in reparative regeneration.     

The acid phosphatase, aminopeptidase and glutamate dehydrogenase activity in the nodose ganglion neurons in emotional stress]

Cell bodies of cardiovascular receptors localized in the rabbit ganglion nodosum exposed to experimental emotional stress were studied histochemically. Two groups of animals were selected for investigation. Rabbits of one group had almost unchanged arterial pressure and small increase in heart rate under emotional stress, while animals of the other group were characterized by strongly marked disturbances of blood circulation leading to the lethal exit at the end of experiment. Activities of lysosomal enzymes--acid phosphatase and aminopeptidase--in the nodose ganglion neurons of the first group rabbits were found to be on the control level, the activity of mitochondrial enzyme, a glutamate-dehydrogenase, was slightly increased, whereas in the second group rabbits all the enzymes studied were significantly activated. A possible correlation between the metabolic changes found in the neurons and the type of hemodynamic changes is discussed.     

The role of the central nervous system imidazoline receptors in cardiovascular manifestations of emotional stress

The effect of central nervous system imidazoline receptors activation on basal blood pressure level, heart rate and arterial baroreceptor reflex in steady state and aversive emotional tension was tested in experiments on alert WKY, SHR and white bastard rats. It was found that the brain imidazoline receptors activation led to arterial baroreceptor reflex rise (both in resting and in emotional tension) and caused an emotional stress pressor effects decrease. No data proving involvement of imidazoline receptors in functioning of the systems maintaining level of blood pressure, were found.     

Possible role of hypoxia and lipid peroxidation in the development of a neurosis-like condition in the rat

The chronic emotional pain stress resulting in a development of neurosis-like state in rats induced an increase of arterial pressure and change of the cardiac rate dynamics under the conditions of functional load. An increase of cardiac mass was also seen without change of masses of the thymus, adrenal glands and the spleen. The rise of activity of cytochromeoxidase and activation of peroxide lipide oxidation (by malonate dialdehyde level) were observed in the cerebral cortex and the hippocampus of neurotized rats. Injection of antioxidant F-801 before each emotional pain stress trial prevented vegetative disturbances, cardiac hypertrophy, and increase of oxidative activity in the brain. The role of peroxide lipide oxidation and that of the factor of hypoxia in development of disturbances caused by neurotization were discussed.     

Repeating of emotional stress prevents development of melanocortin obesity and type 2 diabetes in the mice with the Agouti yellow mutation

Brain melanocortin system (MC-system) participates in regulation of energy homeostasis. Dominant mutation yellow of the Agouti gene leads to the hyperphagia, obesity and type 2 diabetes. Stress is known to inhibit food intake and body weight. The aim of the work was to study effects of repeating emotional stress on food intake and lipid-carbohydrate metabolism in Ay-mice. Male mice of C57B1/6J strain predisposed to the obesity (Ay/a-genotype) and normal (a/a-genotype) were used. In control group food intake, body weight and blood levels of insulin and leptin were increased in Ay/a-mice as compared to a/a-mice. Repeating emotional stress (30 min restraint 3 times a week for 5 weeks) did not alter food intake and indices of lipid-carbohydrate metabolism in a/a-mice and decreased food intake, body weight and blood levels of insulin and leptin in Ay/a-mice. Insulin and leptin blood levels were the same in Ay/a- and a/a-mice on 5 week of treatment. The stress increased basal and stress-induced concentrations of corticosterone to an equal degree in Ay/a- and a/a-mice. Thus, light repeating emotional stress hampered development of obesity and 2 type diabetes in the mice with the Agouti yellow mutation.     

Circadian rhythm disorders and dynamic changes of energy metabolism in rat heart muscle cells

The functional states of pro- and antioxidant systems in blood and heart muscle cells in rats with long-term emotional stress have been studied. It has been shown that daily rhythm disorders produce psycho-emotional stress in animals and that, this is accompanied by quantitative changes in physiological parameters and hormones in the blood. In the present study, it was observed that such stress increased lipid peroxidation in blood and heart muscle cells. Also, activities of antioxidant enzymes, superoxide dismutase, and catalase were diminished, indicating deterioration of the antioxidant system. In addition, there were decreased activities of mitochondrial enzymes participating in energy metabolism, indicating decreased energy levels in heart muscle cells. These results suggest the likelihood that emotional stress is a key factor that can cause a whole range of diseases of the cardiovascular system.     

Therapeutic action of an antioxidant in chronic emotional-pain stress in the rat

Chronic emotional pain stress in rats causes disturbances of the cardiovascular system function (increase in arterial pressure and in heart rate), typical of neuroses-like state, and changes of the vegetative nervous system reactivity tested with functional load by two-hour hypokinesis. Increase in spleen weight is observed as well as a tendency to adrenals weight increase, a decrease of Na, K-ATPase activity and activation of lipid peroxidation in cortical and hippocampal homogenates. Administration of F-801 antioxidant according to therapeutic scheme after the end of stress action, restores normal function of the cardiovascular system, normal reactivity of the vegetative nervous system, decreases adrenals weight and increases the weight of thymus and also normalizes ATPase activity and the level of lipid peroxidation. A backward correlation dependence of the Na, K-ATPase activity on the level of malondialdehyde in the brain tissue has been established.     

Protein metabolism in the cerebral hemispheres during the emotional-algesic stress

Emotional-algesic stress causes essential changes in the protein metabolism of cerebral hemispheres. These changes may be of great importance for the functioning of the brain and cause the disturbances of the higher nervous activity when the organism is influenced by the emotional stress factors.     

Japanese Quail’s Genetic Background Modulates Effects of Chronic Stress on Emotional Reactivity but Not Spatial Learning

Chronic stress is known to enhance mammals’ emotional reactivity and alters several of their cognitive functions, especially spatial learning. Few studies have investigated such effects in birds. We investigated the impact of a two-week stress on Japanese quail’s emotional reactivity and spatial learning. Quail is an avian model widely used in laboratory studies and for extrapolation of data to other poultry species. As sensitivity to chronic stress can be modulated by intrinsic factors, we tested juvenile female Japanese quail from three lines, two of them divergently selected on tonic immobility duration, an indicator of general fearfulness. The different emotional reactivity levels of quail belonging to these lines can be revealed by a large variety of tests. Half of the birds were submitted to repeated unpredictable aversive events for two weeks, whereas the other half were left undisturbed. After this procedure, two tests (open field and emergence tests) evaluated the emotional reactivity of treated and control quails. They were then trained in a T-maze for seven days and their spatial learning was tested. The chronic stress protocol had an impact on resting, preening and foraging in the home cage. As predicted, the emotional reactivity of treated quails, especially those selected for long tonic immobility duration, was higher. Our spatial learning data showed that the treatment enhanced acquisition but not memorization. However, intrinsic fearfulness did not seem to interact with the treatment in this test. According to an inverted U-shaped relationship between stress and cognition, chronic stress can improve the adaptability of birds to a stressful environment. We discussed the mechanisms possibly implied in the increase of emotional reactivity and spatial abilities.     

Influence of prolonged stress on cerebral hemodynamics

The author has investigated the impact of psychological and socio-economic factors on cerebral hemodynamics and development of cerebrovascular disease (CVD). A group of 120 war sufferers with signs of post-traumatic stress disorder and adaptation disturbances, and 120 persons of the control group with no traumatic war experience have been studied. The blood flow velocity and various parameters of spectral frequency analysis have been measured, using the method of transcranial doppler sonography (TCD). A greater number of hemodynamical changes has been found in the group of subjects than in the control group (p < 0.05), in which increase of vasospasm is statistically significant probably as a result of predomination of the sympathetic system stimulation and nicotinic effect on the brain blood vessels. Flow disturbances are relatively more frequent in older subjects, which suggests the rapid development of the atherosclerotic process. The results suggest that exposure to prolonged stress and bad socio-economic factors, through different neurobiological mechanisms, increased the risk for stroke.