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1.
Depending on the type of autonomous regulation, differences in basic levels of interleukin-1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF alpha) were revealed under conditions of hyperthermia in healthy subjects aged 19-21. A parasympathetic type of autonomous regulation corresponded to higher initial levels of proinflammatory cytokinesis, whereas a dominating sympathetic type corresponded to lower levels of the IL-1 beta and TNF alpha. The subjects with the latter type of regulation revealed an increase in the IL-1 beta TNF alpha combined with a higher heat tolerance. The subjects with the former type of regulation revealed a lower heat tolerance. The increase in the alpha2-macroglobulin appeared to be a most typical acute phase response of the human body to hyperthermia.  相似文献   

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The cardiodynamic activity of intravenously administered milrinone was examined in alpha-chloralose anesthetized dogs. Two groups of dogs were used, one pretreated with hexamethonium to block autonomic reflexes, and a second group which received no pretreatment. In the untreated group milrinone produced dose-dependent increases in +dP/dt and heart rate while decreasing both systolic and diastolic blood pressure and left ventricular end diastolic pressure (LVEDP). After treatment with hexamethonium basal heart rate was significantly increased, whereas reflex changes in heart rate in response to i.v. norepinephrine or nitroglycerin were ablated. Systolic, but not diastolic blood pressure was also markedly reduced by hexamethonium. In the presence of hexamethonium responses to milrinone were qualitatively similar to milrinone responses in the absence of hexamethonium. However, the dose-response curves for milrinone were shifted dextrally for changes in +dP/dt and LVEDP, whereas the dose-response curve for blood pressure was shifted sinistrally. Thus, it appears that the autonomic nervous system enhances the effect of milrinone on +dP/dt and LVEDP, but attenuates its effect on blood pressure.  相似文献   

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Sanogenetic monitoring of schoolchildren’s health has demonstrated that, among high school students, the proportion of adolescents with elevated blood pressure (hypertension + hypernormotension) has risen from 15–20% in 8th-year students to 30–50% in 9th- to 11th-year students, while the proportion of adolescents with hypertension was 3.7% in all age groups. The level of blood pressure (BP) was compared with parameters of the autonomic control of the cardiovascular system. A high normal BP in adolescents 13–14 and 17–18 years of age was correlated with the higher proportion of low frequencies in the spectrum of heart rate variability (HRV) and with the lower sensitivity of the arterial baroreflex. At the age of 15–16 years, a high normal BP was accompanied by a reduced heart rate and a higher sensitivity of the arterial baroreflex; BP correlated also with a decrease in power of the high-frequency region of the HRV spectrum. Unlike normotensive age-matched subjects, hypernormotensive adolescents 15–16 years of age have a lower finger blood pressure and reduced relative power of the low-frequency range in the HRV spectrum during the functional test (an increase in the dead space). This may be a result of a functional inadaptability of sympathetic autonomic regulation.  相似文献   

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Inhibitory neurotransmission is primarily governed by γ-aminobutyric acid (GABA) type A receptors (GABAARs). GABAARs are heteropentameric ligand-gated channels formed by the combination of 19 possible subunits. GABAAR subunits are subject to multiple types of regulation, impacting the localization, properties, and function of assembled receptors. GABAARs mediate both phasic (synaptic) and tonic (extrasynaptic) inhibition. While the regulatory mechanisms governing synaptic receptors have begun to be defined, little is known about the regulation of extrasynaptic receptors. We examine the contributions of GABAARs to the pathogenesis of neurodevelopmental disorders, schizophrenia, depression, epilepsy, and stroke, with particular focus on extrasynaptic GABAARs. We suggest that extrasynaptic GABAARs are attractive targets for the treatment of these disorders, and that research should be focused on delineating the mechanisms that regulate extrasynaptic GABAARs, promoting new therapeutic approaches.  相似文献   

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The effect of olfactory stimuli was determined on students (men and women) with different tones of the autonomic nervous system under moderate psychoemotional stress conditions (before an academic test). It was found that the direction of changes in the heart rate variability values of students after olfactory stimulation is determined by the initial tone of the autonomic nervous system. The conclusion was made that olfactory stimuli may be used for correcting psychoemotional stress in students more efficiently if the tone of the autonomic nervous system is taken into consideration.  相似文献   

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The influence of the performance of a computerized visio-spatial task on the state of the autonomic nervous system of PC operators was studied. Statistical characteristics of the operator's heart rhythm during the 3-hour period of work on a computer were analyzed using Baevsky's method of variational pulsometry. The operators were classified in three groups by the character of their reaction to loading. It was suggested that the visio-spatial task performance on a computer could act as a stress factor only on a certain category of people.  相似文献   

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Human breathing and cardiac rhythms become synchronized during voluntary respiration of a subject with the rate higher than the initial cardiac rate. This phenomenon is observed during driving of the breathing rhythm with rhythmical flashes of a photostimulator lamp. The broadest bandwidth of the range of cardiorespiratory synchronization was observed in phlegmatic children, and the narrowest bandwidth was observed in choleric children. The dependence of characteristics of combined heart and breathing rhythmogenesis on temperamental types is determined by the properties of the nervous system, i.e., force, balance, and flexibility.  相似文献   

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A complex study of the functional state of the cardiovascular system of seven- to ten-year-old children with different types of autonomic nervous regulation of the heart rate was performed. It was found that the autonomic nervous system strongly affects the adaptive capacity of the body, bioelectrical processes in the myocardium, the duration of cardiac-cycle phases, the pulse volume, and the tone of large and small cerebral vessels.  相似文献   

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The influence of examination stress on the reactions of the autonomic nervous system in students with different levels of functional mobility of nervous processes (FMNP) was studied. More intense functioning of the cardiovascular system and the strain of all regulatory mechanisms during examination stress were characteristic of individuals with low FMNP, whereas students with high FMNP values were characterized by a weaker strain of the mechanisms of cardiac rhythm regulation, more economical activity of the cardiovascular system, and better performance on the examinations. The activation of humoral, metabolic, and sympathetic effects was observed in all the subjects under examination stress, along with decreased parasympathetic effects on the cardiac rhythm.  相似文献   

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Acute experiments on rats were made to investigate the synaptic transmission of impulses through the inferior mesenteric sympathetic ganglion in health and in different periods after a single injection of the hepatocarcinogen, 4-dimethyl-aminoazobenzene (DAB). It was found that on the second after carcinogen injection there occurs a considerable disturbance of impulse transmission through the sympathetic ganglia. This manifested in the increased latent period of the appearance of action potentials in the intestinal and hypogastric nerves, in the prolonged process of potential conduction, and in the decreased amplitude and frequency of impulse transmission through the ganglion when stimulating the preganglionic nerve. Injection of the carcinogen leads to functional sympathectomy of organs and tissues, thereby creating the conditions for penetration of its metabolites to the cells followed by their malignancy.  相似文献   

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In the denervated mammalian heart a change in right atrial pressure will still alter heart rate (intrinsic rate response, IRR). We have examined the IRR in isolated right atria of the guinea-pig maintained in oxygenated Krebs-Henseleit solution at 37 degrees C, to compare with and extend studies in other species, and to determine whether the guinea-pig is a suitable model for electrophysiological studies of the IRR. Baseline diastolic transmural pressure was set at 2 mmHg. A 6-mmHg increase in right atrial pressure (RAP) caused an increase in atrial rate that reached a steady value of 15 min(-1) after 1-2 min. This response was enhanced by carbamylcholine and attenuated by isoprenaline. The influence of RAP on the rate response to vagal stimulation was examined. With RAP set at 8 mmHg, the reduction in atrial rate following vagal stimulation was 72+/-5% of that at 2 mmHg (n=6, mean+/-S.E., P<0.005). Continuous vagal stimulation produced a sustained bradycardia, and the effect of this bradycardia on the IRR was examined. When atrial rate was reduced 6% by vagal stimulation, the IRR was augmented to 202+/-21% of the control (n=6, P<0.005). This augmentation was larger (P<0.05) than that seen when atrial rate was reduced 8% by carbamylcholine (130+/-8% of control; n=7, P<0.05). Overall, the IRR in the guinea-pig is similar to that in the rabbit, and shows similar interactions with the autonomic nervous system.  相似文献   

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