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Clinical and Experimental Pharmacology... Feb 2017Acute kidney injury (AKI) is a rapid loss of kidney function resulting in accumulation of end metabolic products and associated abnormalities in fluid, electrolyte and... (Review)
Review
Acute kidney injury (AKI) is a rapid loss of kidney function resulting in accumulation of end metabolic products and associated abnormalities in fluid, electrolyte and acid-base homeostasis. The pathophysiology of AKI is complex and multifactorial involving numerous vascular, tubular and inflammatory pathways. Neurohumoral activation with heightened activity of the sympathetic nervous system and renin-angiotensin-aldosterone system play a critical role in this scenario. Inflammation and/or local renal ischaemia are underlying mechanisms triggering renal tissue hypoxia and resultant renal microcirculation dysfunction; a common feature of AKI occurring in numerous clinical conditions leading to a high morbidity and mortality rate. The contribution of renal nerves to the pathogenesis of AKI has been extensively demonstrated in a series of experimental models over the past decades. While this has led to better knowledge of the pathogenesis of human AKI, therapeutic approaches to improve patient outcomes are scarce. Restoration of autonomic regulatory function with vagal nerve stimulation resulting in anti-inflammatory effects and modulation of centrally-mediated mechanisms could be of clinical relevance. Evidence from experimental studies suggests that a therapeutic splenic ultrasound approach may prevent AKI via activation of the cholinergic anti-inflammatory pathway. This review briefly summarizes renal nerve anatomy, basic insights into neural control of renal function in the physiological state and the involvement of the autonomic nervous system in the pathophysiology of AKI chiefly due to sepsis, cardiopulmonary bypass and ischaemia/reperfusion experimental model. Finally, potentially preventive experimental pre-clinical approaches for the treatment of AKI aimed at sympathetic inhibition and/or parasympathetic stimulation are presented.
Topics: Acute Kidney Injury; Animals; Autonomic Nervous System; Humans; Kidney; Kidney Function Tests; Microcirculation; Renal Circulation; Vagus Nerve Stimulation
PubMed: 28116780
DOI: 10.1111/1440-1681.12694 -
American Journal of Audiology Oct 2017This paper consists of 2 parts. The purpose of Part 1 was to review the potential influence of internal (person-related) factors on listening effort. The purpose of Part... (Review)
Review
PURPOSE
This paper consists of 2 parts. The purpose of Part 1 was to review the potential influence of internal (person-related) factors on listening effort. The purpose of Part 2 was to present, in support of Part 1, preliminary data illustrating the interactive effects of an external factor (task demand) and an internal factor (evaluative threat) on autonomic nervous system measures.
METHOD
For Part 1, we provided a brief narrative review of motivation and stress as modulators of listening effort. For Part 2, we described preliminary data from a study using a repeated-measures (2 × 2) design involving manipulations of task demand (high, low) and evaluative threat (high, low). The low-demand task consisted of repetition of sentences from a narrative. The high-demand task consisted of answering questions about the narrative, requiring both comprehension and recall. During the high evaluative threat condition, participants were filmed and told that their video recordings would be evaluated by a panel of experts. During the low evaluative threat condition, no filming occurred; participants were instructed to "do your best." Skin conductance (sympathetic nervous system activity) and heart rate variability (HRV, parasympathetic activity) were measured during the listening tasks. The HRV measure was the root mean square of successive differences of adjacent interbeat intervals. Twelve adults with hearing loss participated.
RESULTS
Skin conductance increased and HRV decreased relative to baseline (no task) for all listening conditions. Skin conductance increased significantly with an increase in evaluative threat, but only for the more demanding task. There was no significant change in HRV in response to increasing evaluative threat or task demand.
CONCLUSIONS
Listening effort may be influenced by factors other than task difficulty, as reviewed in Part 1. This idea is supported by the preliminary data indicating that the sympathetic nervous system response to task demand is modulated by social evaluative threat. More work is needed to determine the relative contributions of motivation and emotional stress on physiological responses during listening tasks.
Topics: Aged; Aged, 80 and over; Auditory Perception; Autonomic Nervous System; Female; Galvanic Skin Response; Heart Rate; Humans; Male; Middle Aged; Motivation; Stress, Psychological; Task Performance and Analysis
PubMed: 29049621
DOI: 10.1044/2017_AJA-16-0133 -
Applied Psychophysiology and Biofeedback Dec 2022Heart rate variabfility (HRV) has been a focal point throughout my academic history. To put into perspective, I have published studies spanning seven decades focusing on... (Review)
Review
Heart rate variabfility (HRV) has been a focal point throughout my academic history. To put into perspective, I have published studies spanning seven decades focusing on HRV (1969-2022). My interest in HRV started early in graduate school and continues to be an important portal informing my theoretical perspective. The current paper tracks some of this history, which started as an empirical observation and moved through several scientific stages including development of quantitative methods and investigations of neural mechanisms. Along this journey a variety of hypotheses were tested including the relative sensitivity of HRV metrics to neural mechanisms, psychological processes, and medical diagnoses. In addition, the research led to the identification of portal of intervention that have become strategies to optimize mental and physical health. These apparent disparate programs of inquiry have been tightly merged as the Polyvagal Theory evolved. In the sections below, I have shared my personal journey through these stages of scientific inquiry and my attempts to integrate the new knowledge in an expansive theoretical model.
Topics: Humans; Heart Rate; Autonomic Nervous System; Vagus Nerve
PubMed: 36136145
DOI: 10.1007/s10484-022-09559-x -
Circulation. Cardiovascular Imaging Jun 2024
Topics: Humans; Autonomic Nervous System; Autonomic Nervous System Diseases
PubMed: 38868943
DOI: 10.1161/CIRCIMAGING.124.017028 -
Autonomic Neuroscience : Basic &... Sep 2015Most early studies of the role of nucleotides in development have evidenced their crucial importance as carriers of energy in all organisms. However, an increasing... (Review)
Review
Most early studies of the role of nucleotides in development have evidenced their crucial importance as carriers of energy in all organisms. However, an increasing number of studies are now available to suggest that purines and pyrimidines, acting as extracellular ligands specifically on receptors of the plasma membrane, may play a pivotal role throughout pre- and postnatal development in a wide variety of organisms including amphibians, birds, and mammals. Purinergic receptor expression and functions have been studied in the development of many organs, including the autonomic nervous system (ANS). Nucleotide receptors can induce a multiplicity of cellular signalling pathways via crosstalk with bioactive molecules acting on growth factors and neurotransmitter receptors which are fundamental for the development of a mature and functional ANS. Purines and pyrimidines may influence all the stages of neuronal development, including neural cell proliferation, migration, differentiation and phenotype determination of differentiated cells. Indeed, the normal development of the ANS is disturbed by dysfunction of purinergic signalling in animal models. To establish the primitive and fundamental nature of purinergic neurotransmission in the ontogeny of the ANS, in this review the roles of purines and pyrimidines as signalling molecules during embryological and postnatal development are considered.
Topics: Animals; Autonomic Nervous System; Humans; Receptors, Purinergic
PubMed: 25953245
DOI: 10.1016/j.autneu.2015.04.009 -
Progress in Brain Research 2023This systematic review explores the influence of silence on the autonomic nervous system. The Polyvagal Theory has been used as a reference model to describe the...
This systematic review explores the influence of silence on the autonomic nervous system. The Polyvagal Theory has been used as a reference model to describe the autonomic nervous system by explaining its role in emotional regulation, social engagement, and adaptive physiological responses. PubMed, Scopus, PsycInfo, EMBASE, and Google Scholar were systematically searched up until July 2023 for relevant studies. The literature search yielded 511 results, and 37 studies were eventually included in this review. Silence affects the autonomic nervous system differently based on whether it is inner or outer silence. Inner silence enhances activity of the ventral vagus, favoring social engagement, and reducing sympathetic nervous system activity and physiological stress. Outer silence, conversely, can induce a heightened state of alertness, potentially triggering vagal brake removal and sympathetic nervous system activation, though with training, it can foster inner silence, preventing such activation. The autonomic nervous system response to silence can also be influenced by other factors such as context, familiarity with silence, presence and quality of outer noise, and empathy.
Topics: Humans; Autonomic Nervous System; Vagus Nerve; Emotional Regulation; Empathy; Recognition, Psychology
PubMed: 37714570
DOI: 10.1016/bs.pbr.2023.08.001 -
High Blood Pressure & Cardiovascular... Jun 2016Hypertension is a leading cause of morbidity and mortality worldwide, being the major risk factor for stroke, heart failure and kidney diseases. During past decades,... (Review)
Review
Hypertension is a leading cause of morbidity and mortality worldwide, being the major risk factor for stroke, heart failure and kidney diseases. During past decades, several therapies have been developed to afford an optimal regulation of blood pressure levels. However, the prevalence of uncontrolled hypertension still represents an unsolved problem, with a number of patients resistant as well to all ongoing antihypertensive treatments, raising unsolved mechanistic challenges. In the last years, the most attractive novelty in hypertension research postulated that immune system may have a crucial role in blood pressure elevation, as well as in end-organ damage. Here we briefly review the most important contribution revealing the role of innate and adaptive immune system in hypertension. Moreover, we discuss evidence showing that, in the regulation of body hemodynamics, the immune system and the autonomic nervous systems serve as two major sensory organs whose interaction is crucial for blood pressure increase and target organ damage in hypertension.
Topics: Adaptive Immunity; Animals; Autonomic Nervous System; Blood Pressure; Cardiovascular System; Humans; Hypertension; Immunity, Innate; Neuroimmunomodulation; T-Lymphocytes
PubMed: 27080378
DOI: 10.1007/s40292-016-0141-8 -
Acta Cardiologica Aug 2023The role of the autonomic nervous system in the onset of supraventricular and ventricular arrhythmias is well established. It can be analysed by the spontaneous... (Review)
Review
The role of the autonomic nervous system in the onset of supraventricular and ventricular arrhythmias is well established. It can be analysed by the spontaneous behaviour of the heart rate with ambulatory ECG recordings, through heart rate variability measurements. Input of heart rate variability parameters into artificial intelligence models to make predictions regarding the detection or forecast of rhythm disorders is becoming routine and neuromodulation techniques are now increasingly used for their treatment. All this warrants a reappraisal of the use of heart rate variability for autonomic nervous system assessment.Measurements performed over long periods such as 24H-variance, total power, deceleration capacity, and turbulence are suitable for estimating the individual basal autonomic status. Spectral measurements performed over short periods provide information on the dynamics of systems that disrupt this basal balance and may be part of the triggers of arrhythmias, as well as premature atrial or ventricular beats. All heart rate variability measurements essentially reflect the modulations of the parasympathetic nervous system which are superimposed on the impulses of the adrenergic system. Although heart rate variability parameters have been shown to be useful for risk stratification in patients with myocardial infarction and patients with heart failure, they are not part of the criteria for prophylactic implantation of an intracardiac defibrillator, because of their high variability and the improved treatment of myocardial infarction. Graphical methods such as Poincaré plots allow quick screening of atrial fibrillation and are set to play an important role in the e-cardiology networks. Although mathematical and computational techniques allow manipulation of the ECG signal to extract information and permit their use in predictive models for individual cardiac risk stratification, their explicability remains difficult and making inferences about the activity of the ANS from these models must remain cautious.
Topics: Humans; Heart Rate; Artificial Intelligence; Autonomic Nervous System; Heart; Myocardial Infarction; Atrial Fibrillation; Heart Atria
PubMed: 36803313
DOI: 10.1080/00015385.2023.2177371 -
American Journal of Otolaryngology 2018The inferior turbinate has well-recognized respiratory and immune functions to provide the airway with appropriate warmth, humidification, and filtration of the inspired... (Review)
Review
The inferior turbinate has well-recognized respiratory and immune functions to provide the airway with appropriate warmth, humidification, and filtration of the inspired air while sampling the environment for pathogens. Normal functioning of the inferior turbinate relies on an intact autonomic system to maintain homeostasis within the nasal cavity. The autonomic nervous system innervates the submucosal glands and the vasculature within the inferior turbinate, resulting in control of major turbinate functions: nasal secretions, nasal patency, warmth, and humidification. This review will summarize the autonomic innervations of the turbinates, both the normal and abnormal autonomic processes that contribute to the turbinate functions, and the clinical considerations regarding optimal functioning of the turbinate autonomic system.
Topics: Autonomic Nervous System; Humans; Turbinates
PubMed: 30193745
DOI: 10.1016/j.amjoto.2018.08.009 -
Vascular Pharmacology Aug 2015In the last decades, a large body of experimental and clinical evidence has been accumulated showing that cardiovascular diseases are often accompanied by an imbalance... (Review)
Review
In the last decades, a large body of experimental and clinical evidence has been accumulated showing that cardiovascular diseases are often accompanied by an imbalance in the sympathetic-vagal outflow to the heart, resulting in a chronic adrenergic activation. The arterial baroreceptor system is a key component of mechanisms contributing to the neural regulation of the cardiovascular system. Several methods have been proposed to assess autonomic activity by analyzing heart rate and blood pressure changes either spontaneously occurring or following provocations. The autonomic nervous system has been regarded as one of the putative mechanisms involved into the beneficial effects of exposure to n-3 fatty acids observed in epidemiological studies. The aim of the present review is to provide an update on the clinical evidence proposed so far linking exposure to n-3 fatty acids to autonomic nervous system modulation.
Topics: Animals; Autonomic Nervous System; Blood Pressure; Cardiovascular Diseases; Fatty Acids, Omega-3; Heart Rate; Humans; Neural Pathways; Vagus Nerve
PubMed: 25869497
DOI: 10.1016/j.vph.2015.02.005