Cardiovascular Consequences of a Mutant Thyroid Hormone Receptor α1

2010 ◽  
Vol 6 (2) ◽  
pp. 51 ◽  
Author(s):  
Jens Mittag ◽  
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Thyroid Hormone ◽  
Cardiovascular System ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Cardiac Activity ◽  
Autonomic Nervous

Thyroid hormone has long been known for its profound direct effects on the cardiovascular system, but its interactions with the autonomic nervous system controlling cardiac activity still remain enigmatic. Recently, mice heterozygous for a mutant thyroid hormone receptor α1 (TRα1+/m) have been generated and their analysis has provided new insights into the actions of thyroid hormone on the cardiovascular system. The mutant TRα1 caused many symptoms resembling hypothyroidism, such as bradycardia, as well as reduced contraction and delayed relaxation time of isolated cardiomyocytes. While no abnormalities were detected in the autonomic regulation of the basal heart rate using pharmacological denervation, an impaired adjustment of the autonomic nervous system could be observed in TRα1+/m mice on activity, stress or increased temperature. The results thus confirm the important role of TRα1 in maintaining the intrinsic properties of the heart and demonstrate a novel role for TRα1 in the adaptations of the autonomic nervous system controlling the heart rate under non-baseline conditions.

Cardiovascular Consequences of a Mutant Thyroid Hormone Receptor α1

2011 ◽  
Vol 07 (01) ◽  
pp. 55
Author(s):  
Jens Mittag ◽  
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Thyroid Hormone ◽  
Cardiovascular System ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Cardiac Activity ◽  
Autonomic Nervous

Thyroid hormone has long been known for its profound direct effects on the cardiovascular system, but its interactions with the autonomic nervous system controlling cardiac activity still remain enigmatic. Recently, mice heterozygous for a mutant thyroid hormone receptor 〈1 (TR〈1+/m) have been generated and their analysis has provided new insights into the actions of thyroid hormone on the cardiovascular system. The mutant TR〈1 caused many symptoms resembling hypothyroidism, such as bradycardia, as well as reduced contraction and delayed relaxation time of isolated cardiomyocytes. While no abnormalities were detected in the autonomic regulation of the basal heart rate using pharmacologic denervation, an impaired adjustment of the autonomic nervous system could be observed in TR〈1+/m mice on activity, stress, or increased temperature. The results thus confirm the important role of TR〈1 in maintaining the intrinsic properties of the heart and demonstrate a novel role for TR〈1 in the adaptations of the autonomic nervous system controlling the heart rate under non-baseline conditions.

scholarly journals Adaptations of the Autonomous Nervous System Controlling Heart Rate Are Impaired by a Mutant Thyroid Hormone Receptor-α1

Endocrinology ◽  
2010 ◽  
Vol 151 (5) ◽  
pp. 2388-2395 ◽  
Author(s):  
Jens Mittag ◽  
Benjamin Davis ◽  
Milica Vujovic ◽  
Anders Arner ◽  
Björn Vennström
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Thyroid Hormone ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Cardiac Activity ◽  
Autonomic Control ◽  
Autonomous Nervous System ◽  
Wild Type ◽  
Brown Adipose

Thyroid hormone has profound direct effects on cardiac function, but the hormonal interactions with the autonomic control of heart rate are unclear. Because thyroid hormone receptor (TR)-α1 has been implicated in the autonomic control of brown adipose energy metabolism, it might also play an important role in the central autonomic control of heart rate. Thus, we aimed to analyze the role of TRα1 signaling in the autonomic control of heart rate using an implantable radio telemetry system. We identified that mice expressing the mutant TRα1R384C (TRα1+m mice) displayed a mild bradycardia, which becomes more pronounced during night activity or on stress and is accompanied by a reduced expression of nucleotide-gated potassium channel 2 mRNA in the heart. Pharmacological blockage with scopolamine and the β-adrenergic receptor antagonist timolol revealed that the autonomic control of cardiac activity was similar to that in wild-type mice at room temperature. However, at thermoneutrality, in which the regulation of heart rate switches from sympathetic to parasympathetic in wild-type mice, TRα1+m mice maintained sympathetic stimulation and failed to activate parasympathetic signaling. Our findings demonstrate a novel role for TRα1 in the adaptation of cardiac activity by the autonomic nervous system and suggest that human patients with a similar mutation in TRα1 might exhibit a deficit in cardiac adaptation to stress or physical activity and an increased sensitivity to β-blockers.

scholarly journals Altered Autonomic Nervous System Reactivity to Pain in Trigeminal Neuralgia

2015 ◽  
Vol 42 (2) ◽  
pp. 125-131 ◽  
Author(s):  
Guillaume Léonard ◽  
Philippe Chalaye ◽  
Philippe Goffaux ◽  
David Mathieu ◽  
Isabelle Gaumond ◽  
...  
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Trigeminal Neuralgia ◽  
Cold Pressor Test ◽  
Cardiac Activity ◽  
Cold Pressor ◽  
Healthy Controls ◽  
P Values ◽  
Autonomic Nervous

AbstractBackground: In the past two decades, there has been increasing evidence to suggest that trigeminal neuralgia (TN) may be linked to a dysfunction of the autonomic nervous system (ANS). The aim of the present study was to formally test this hypothesis by comparing the reactivity of the ANS to experimental pain in a population of TN patients and healthy controls. Methods: Twelve patients diagnosed with classical TN and 12 healthy controls participated in the study. Cardiac activity was assessed while participants were instructed to rest and again during a cold pressor test (CPT). Heart rate variability analyses were performed off-line to obtain parasympathetic (high-frequency) and sympathetic (low-frequency) indices. Results: At baseline, ANS measures did not differ between healthy controls and TN patients, and both groups showed a similar increase in heart rate during the CPT (all p values >0.05). However, TN patients showed a greater increase in cardiac sympathetic activity and a greater decrease in cardiac parasympathetic activity during CPT compared with healthy controls (all p values <0.05). Importantly, changes in sympathetic reactivity, from baseline to CPT, were negatively associated with the number of pain paroxysms experienced each day by TN patients in the preceding week (r=−.58, p<0.05). Conclusions: These results suggest that TN, like many other short-lasting, unilateral facial pain conditions, is linked to ANS alterations. Future studies are required to determine if the altered ANS response observed in TN patients is a cause or a consequence of TN pain

19. Role of the autonomic nervous system in blood pressure and heart rate variability in conscious rats

1991 ◽  
Vol 9 (6) ◽  
pp. S429
Author(s):  
C. Cerutti ◽  
M. Lo ◽  
Claude Julien ◽  
Madelaine Vincent ◽  
C. Paultre ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Conscious Rats ◽  
Autonomic Nervous

scholarly journals Evaluation of Autonomic Nervous System Changes Using Short-term Heart Rate Variability During Apnea

2020 ◽  
Author(s):  
Baolin He ◽  
Wenyu Li ◽  
Xiaotong Zhang ◽  
Yanan Wu ◽  
Jing Liu ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Physiological State ◽  
Cardiac Activity ◽  
Normal Function ◽  
Short Term ◽  
Autonomic Nervous ◽  
Respiratory State

Abstract Background: Frequent cessations of respiration can greatly increase the prevalence rate of arrhythmia. It has been confirmed that cardiac activity is regulated by autonomic nervous system (ANS). And heart rate variability (HRV) is widely used as a method to evaluate the function of ANS. Therefore, we analyzed whether apnea can affect the balance and normal function of ANS using short-term HRV indices. Methods: Forty-five healthy subjects were asked to breathe normally and hold their breathing to simulate 10 times apnea. Thirty-six patients from the dataset of a sleep laboratory for the diagnosis of sleep disorders with 10 times apnea were included in analysis. We calculated short-term HRV indices of subjects in normal respiratory and apneic states, respectively. Results: Compared with normal respiratory state, respiration cease would lead to the values of the mean-RR, nLF, LF/HF, and α1 were significantly increase whereas the values of rMSSD and nHF were significantly decrease. Conclusions: Cessations of respiration would lead to an imbalance in function of ANS, as well as an increase in fractal characteristics of the heart. These changes in physiological state are likely to induce and cause the occurrence of arrhythmia, which is regulated by ANS.

The Role of Autonomic Nervous System and Baroreflex in the Pattern of Heart Rate Fragmentation

2020 ◽  
Vol 34 (S1) ◽  
pp. 1-1
Author(s):  
Thaís Marques Silva ◽  
Jaci Airton Castania ◽  
Carlos Alberto Aguiar Silva ◽  
Helio Cesar Salgado ◽  
Luiz Eduardo Virgílio Silva ◽  
...  
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Autonomic Nervous

Autonomic nervous system in euthymic patients with bipolar affective disorder

2011 ◽  
Vol 26 (S2) ◽  
pp. 222-222
Author(s):  
K. Latalova ◽  
T. Diveky ◽  
A. Grambal ◽  
D. Kamaradova ◽  
H. Velartova ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Age Of Onset ◽  
Bipolar Affective Disorder ◽  
Cardiac Activity ◽  
Diagnostic Systems ◽  
Autonomic Nervous ◽  
Bipolar Patients

BackgroundAutonomic nervous system (ANS) dysfunction and reduced heart rate variability (HRV) have been reported in a wide variety of psychiatric disorders, but have not been well characterized in bipolar patiens in remission. We recorded cardiac activity and assessed HRV in bipolar outpatients in remission.AimsAscertain if ANS decrease with the age of the patient; ascertain relation between activity of ANS and level of dissociation, and other components (age of patients, and age of disorder, dosage of psychotropic medication)MethodsAutonomic nervous system (ANS) has been evaluated during orthostatic change in three positions (1- lie down 5 minutes, 2 – stand up 5 minutes, 3 – lie down 5 minutes). The functioning of the ANS has been measured by the diagnostic systems that are using the power spectral analysis which quantifies the heart rate variability (HRV) was assessed using time domain, frequency domain, and nonlinear analyses in 23 bipolar patients in remission.ResultsWe found highly statistically significant negative correlations between level of dissociation measured by DES and most of parameters of ANS. We found negative correlations between the age of the patient and activity of ANS, and negative correlations between activity of ANS and duration and onset of disorder.ConclusionsAutonomic dysregulation is associated with bipolar disorder in remission and has relation to level of dissociation and probably to age of patiens and age of onset and duration of disorder.Supported by grant IGA MZ ČR NT11047

scholarly journals Autonomic Nervous System Function in Chronic Exogenous Subclinical Thyrotoxicosis and the Effect of Restoring Euthyroidism

2008 ◽  
Vol 93 (7) ◽  
pp. 2835-2841 ◽  
Author(s):  
Carmen F. A. Eustatia-Rutten ◽  
Eleonora P. M. Corssmit ◽  
Karen A. Heemstra ◽  
Johannes W. A. Smit ◽  
Rik C. Schoemaker ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Thyroid Hormone ◽  
Urinary Excretion ◽  
Vanillylmandelic Acid ◽  
Subclinical Hyperthyroidism ◽  
Autonomic Nervous

Abstract Context: Knowledge on the relationship between the autonomic nervous system and subclinical hyperthyroidism is mainly based upon cross-sectional studies in heterogeneous patient populations, and the effect of restoration to euthyroidism in subclinical hyperthyroidism has not been studied. Objective: We investigated the long-term effects of exogenous subclinical hyperthyroidism on the autonomic nervous system and the potential effects of restoration of euthyroidism. Design: This was a prospective single-blinded, placebo-controlled, randomized trial. Setting: The study was performed at a university hospital. Patients: A total of 25 patients who were on more than 10-yr TSH suppressive therapy after thyroidectomy was examined. Intervention: Patients were studied at baseline and subsequently randomized to a 6-month thyroid hormone substitution regimen to obtain either euthyroidism or maintenance of the subclinical hyperthyroid state. Main Outcome Measures: Urinary excretion of catecholamines and heart rate variability were measured. Baseline data of the subclinical hyperthyroidism patients were compared with data obtained in patients with hyperthyroidism and controls. Results: Urinary excretion of norepinephrine and vanillylmandelic acid was higher in the subclinical hyperthyroidism patients compared with controls and lower compared with patients with overt hyperthyroidism. Heart rate variability was lower in patients with hyperthyroidism, intermediate in subclinical hyperthyroidism patients, and highest in the healthy controls. No differences were observed after restoration of euthyroidism. Conclusions: Long-term exogenous subclinical hyperthyroidism has effects on the autonomic nervous system measured by heart rate variability and urinary catecholamine excretion. No differences were observed after restoration to euthyroidism. This may indicate the occurrence of irreversible changes or adaptation during long-term exposure to excess thyroid hormone that is not remedied by 6-month euthyroidism.

Analysis of Heart rate Variability and Implication of Different Factors on Heart Rate Variability

2020 ◽  
Vol 16 ◽  
Author(s):  
Reena Tiwari ◽  
Ravindra Kumar ◽  
Sujata Malik ◽  
Tilak Raj ◽  
Punit Kumar
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Parasympathetic Nervous System ◽  
Invasive Technique ◽  
Clinical Practices ◽  
Autonomic Nervous ◽  
Pathological Conditions

Background:: The heart is the central organ of the circulatory system which maintains the flow of blood along with the transport of nutrients to different cells and tissues. A well-functioning cardiac state is a complicated mode of changeability. A healthy heart is not only about oscillation as the rhythmometer is not the same in every circumstance. Heart rate shows variations so that it can be regulated according to psychophysiological conditions to maintain the effect of the internal-external stimulus. Objective:: The main objective of this review is to provide a piece of all-inclusive information about heart rate variability (HRV) and different variables affecting HRV. The direct interconnection among factors and so that HRV can be used in clinical practices. Methods:: This review article contains a detailed survey of literature about HRV available in different online sources such as; Google Scholar, Science Direct, PubMed, and Web of Science, etc. In this review, the authors have focused on the role of the autonomic nervous system in the regulation of HRV and the role of various factors affecting HRV. Results:: The variation in the time between two heartbeats is termed as HRV. It is one of the indicators of many pathological conditions related to cardiovascular health. It provided reliable information about the interaction of the sympathetic and parasympathetic nervous systems. The analysis of the variation of heart rate is a well-known non-invasive technique to identify the functioning of the autonomic nervous system. The autonomic nervous system (ANS) depends on the sympathetic and parasympathetic nervous system for transferring information. The cardio-accelerating center, lungs, and non-striated muscles are innervated by cardiac sympathetic nerves. This division of ANS latches upon the heart accordingly via the cervicothoracic ganglion and vagus nerve. It is found that cardiac normal variability depends upon this stimulation towards the sinoatrial node (pacemaker) which can be evaluated by analyzing the HRV. In human- based studies, it has been found that low level of HRV is one of the main causes of death rate among adults. Hence, HRV helps in identifying the risk of cardiac diseases and the state of ANS. Conclusion:: The heart plays a vital role in the human body and the well-functioning of the cardiac system is the need for a healthy life. The heart contains its nervous system termed as neurocardio system in which ANS plays a key role in which the sympathetic and parasympathetic system interplay to regulate HRV. High HRV is associated with healthy condition while low HRV is associated with pathological conditions. The HRV is influenced by various variables such as; pathological, physiological, psychological, environmental factors, lifestyle factors, and genetic factors, etc.

Role of pulse wave velocity for assessing autonomic nervous system activities in reference to heart rate variability

1996 ◽  
Vol 21 (1) ◽  
pp. 81-90 ◽  
Author(s):  
M. Okada ◽  
T. Matsuto ◽  
S. Satoh ◽  
S. Igarashi ◽  
M. Baba ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Pulse Wave Velocity ◽  
Wave Velocity ◽  
Pulse Wave ◽  
Autonomic Nervous
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