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Macaque cardiac physiology is sensitive to the valence of passively viewed sensory stimuli.
Autonomic nervous system activity is an important component of affective experience. We demonstrate in the rhesus monkey that both the sympathetic and parasympathetic branches of the autonomic nervous system respond differentially to the affective valence of passively viewed video stimuli. We recorded cardiac impedance and an electrocardiogram while adult macaques watched a series of 300 30-second videos that varied in their affective content. We found that sympathetic activity (as measured by cardiac pre-ejection period) increased and parasympathetic activity (as measured by respiratory sinus arrhythmia) decreased as video content changes from positive to negative. These findings parallel the relationship between autonomic nervous system responsivity and valence of stimuli in humans. Given the relationship between human cardiac physiology and affective processing, these findings suggest that macaque cardiac physiology may be an index of affect in nonverbal animals
Effect of obesity on autonomic nervous system
The present study was carried out on 100 volunteers of which 50 subjects with BMI > 30kg/m2 were included in study group and 50 subjects with BMI < 30kg/m2 (non obese) were included in control group. The functioning of Autonomic nervous system was evaluated by six non-invasive tests- four of which were based mainly on parasympathetic control (30:15 ratio, standing to lying ratio (S/L ratio), expiration/inspiration ratio (E/I ratio) and valsalva maneuver) and two on sympathetic control (Blood pressure response to standing and cold pressor test). The results of the present study showed significantly low (p=0.001) S/L ratio in study group (1.04 ± 0.12) when compared to controls (1.12 ± 0.11) indicating impaired parasympathetic function. The mean change in sytolic blood pressure before and after cold pressor test (CPT) was less in study group (7.12 ± 5.28) as compared to control group (10.38 ± 6.35) and this was statistically significant (p=0.006) indicating impaired sympatheitc function. Thus ,in obese both division of ANS are affected which may be the cause of various cardiovascular complications
Thermal signatures of human pheromones in sexual and reproductive behaviour
Chemically mediated sexual communication in humans has been largely neglected due to its non-conscious and relatively concealed nature. However, menstrual cycle synchronisation, puberty onset in young pre-pubertal girls exposed to their stepfather, and consanguinity avoidance suggest a function in the physiological regulation of sexual and reproductive behaviour in humans. These phenomena are related to activation of the limbic system by pheromones. On the basis of sexually dimorphic activation of brain hypothalamic areas and the control of body temperature via the hypothalamus, our hypothesis is that human sexual pheromones can induce thermal effects that can be revealed by high-resolution thermal infrared imaging. Here we show that in women, male sexual pheromones induce thermal effects that are linked to the ovarian cycle. These findings suggest a dramatic influence of pheromones on human sexual and reproductive behaviour through neuroendocrine brain control, established on the plesiomorphic nature of chemical communication across species
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Distribution of α7 Nicotinic Acetylcholine Receptor Subunit mRNA in the Developing Mouse.
Homomeric α7 nicotinic acetylcholine receptors (nAChRs) are abundantly expressed in the central and peripheral nervous system (CNS and PNS, respectively), and spinal cord. In addition, expression and functional responses have been reported in non-neuronal tissue. In the nervous system, α7 nAChR subunit expression appears early during embryonic development and is often transiently upregulated, but little is known about their prenatal expression outside of the nervous system. For understanding potential short-term and long-term effects of gestational nicotine exposure, it is important to know the temporal and spatial expression of α7 nAChRs throughout the body. To that end, we studied the expression of α7 nAChR subunit mRNA using highly sensitive isotopic in situ hybridization in embryonic and neonatal whole-body mouse sections starting at gestational day 13. The results revealed expression of α7 mRNA as early as embryonic day 13 in the PNS, including dorsal root ganglia, parasympathetic and sympathetic ganglia, with the strongest expression in the superior cervical ganglion, and low to moderate levels were detected in brain and spinal cord, respectively, which rapidly increased in intensity with embryonic age. In addition, robust α7 mRNA expression was detected in the adrenal medulla, and low to moderate expression in selected peripheral tissues during embryonic development, potentially related to cells derived from the neural crest. Little or no mRNA expression was detected in thymus or spleen, sites of immune cell maturation. The results suggest that prenatal nicotine exposure could potentially affect the nervous system with limited effects in non-neural tissues
Variability of the Heart Rhythm as an Additional Marker for Determining Vegetative Functions in Patients with Chronic Cerebral Ischemia
Aim. Practical cardiology is in constant search for non-invasive vascular risk markers. Heart rhythm reflects the body\u27s response to various stimuli of the external and internal environment. Heart rate variability (HRV) has a prognostic and diagnostic value and allows timely identification of conditions that threaten life. The results of an instrumental examination of heart rhythm fluctuations in patients suffering from chronic cerebral ischemia against the background of angina pectoris of different functional classes allows to evaluate the prognosis of the disease and select the appropriate treatment.Materials and methods. An assessment of the state of the mechanisms of regulation of physiological functions in patients suffering from chronic cerebral ischemia against the background of angina pectoris of different functional classes was obtained according to spectral and temporal analysis of heart rate variability using electrocardiographic monitoring. The spectral characteristics of the heart rate variability were studied: HF (high frequency), LF (low frequency), VLF (very low frequency).Results. Heart rhythm regulation in patients with chronic cerebral ischemia occurred under the influence of neurohumoral mechanisms. The imbalance of functional systems was caused by changes in the autonomic nervous system, which disrupted the normal functioning of the sympathetic and parasympathetic parts. We marked decrease in the activity of the parasympathetic autonomic nervous system, which changed the indices of spectral analysis, while the high-frequency component of the spectrum was characterized by a decrease, while the low-frequency component was characterized by an increase. The progression of stable angina of tension (SAT) in patients with chronic cerebral ischemia (CCI) occurred with disruption of the autonomic nervous system (ANS) and was associated with a shift in the physiological response towards sympathetic activity. This was particularly pronounced in patients in group 2 with CCI on the background of SAT III FC, as the regulatory mechanisms were in a critical state of tension against the background of long-term chronic ischemia, they showed a high level of humoral modulation of regulatory mechanisms, which was manifested by excessive VLF and high-frequency oscillations.Conclusions. A connection was established between the autonomic nervous system and chronic cerebral ischemia, which was expressed in the imbalance of the ANS, associated with reliable signs of the dominant sympathetic system, which was associated with the progression of stable angina of tension
The role of inhibitory G proteins and regulators of G protein signaling in the in vivo control of heart rate and predisposition to cardiac arrhythmias
Inhibitory heterotrimeric G proteins and the control of heart rate. The activation of cell signaling pathways involving inhibitory heterotrimeric G proteins acts to slow the heart rate via modulation of ion channels. A large number of Regulators of G protein signalings (RGSs) can act as GTPase accelerating proteins to inhibitory G proteins and thus it is important to understand the network of RGS\G-protein interaction. We will review our recent findings on in vivo heart rate control in mice with global genetic deletion of various inhibitory G protein alpha subunits. We will discuss potential central and peripheral contributions to the phenotype and the controversies in the literature
Vagal nerve stimulation therapy: what is being stimulated?
Vagal nerve stimulation in cardiac therapy involves delivering electrical current to the vagal sympathetic complex in patients experiencing heart failure. The therapy has shown promise but the mechanisms by which any benefit accrues is not understood. In this paper we model the response to increased levels of stimulation of individual components of the vagal sympathetic complex as a differential activation of each component in the control of heart rate. The model provides insight beyond what is available in the animal experiment in as much as allowing the simultaneous assessment of neuronal activity throughout the cardiac neural axis. The results indicate that there is sensitivity of the neural network to low level subthreshold stimulation. This leads us to propose that the chronic effects of vagal nerve stimulation therapy lie within the indirect pathways that target intrinsic cardiac local circuit neurons because they have the capacity for plasticity
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