1
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Battaglia S, Nazzi C, Lonsdorf TB, Thayer JF. Neuropsychobiology of fear-induced bradycardia in humans: progress and pitfalls. Mol Psychiatry 2024:10.1038/s41380-024-02600-x. [PMID: 38862673 DOI: 10.1038/s41380-024-02600-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 04/17/2024] [Accepted: 05/07/2024] [Indexed: 06/13/2024]
Abstract
In the last century, the paradigm of fear conditioning has greatly evolved in a variety of scientific fields. The techniques, protocols, and analysis methods now most used have undergone a progressive development, theoretical and technological, improving the quality of scientific productions. Fear-induced bradycardia is among these techniques and represents the temporary deceleration of heart beats in response to negative outcomes. However, it has often been used as a secondary measure to assess defensive responding to threat, along other more popular techniques. In this review, we aim at paving the road for its employment as an additional tool in fear conditioning experiments in humans. After an overview of the studies carried out throughout the last century, we describe more recent evidence up to the most contemporary research insights. Lastly, we provide some guidelines concerning the best practices to adopt in human fear conditioning studies which aim to investigate fear-induced bradycardia.
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Affiliation(s)
- Simone Battaglia
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna, Bologna, Italy
- Department of Psychology, University of Torino, Torino, Italy
| | - Claudio Nazzi
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna, Bologna, Italy
| | - Tina B Lonsdorf
- Department of Systems Neuroscience, University Medical Center Hamburg Eppendorf, Hamburg, Germany
- Department of Psychology, Section for Biological Psychology and Cognitive Neuroscience, University of Bielefeld, Bielefeld, Germany
| | - Julian F Thayer
- Department of Psychological Science, 4201 Social and Behavioral Sciences Gateway, University of California, Irvine, CA, USA.
- Department of Psychology, The Ohio State University, Columbus, OH, USA.
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2
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Ashton JL, Prince B, Sands G, Argent L, Anderson M, Smith JEG, Tedoldi A, Ahmad A, Baddeley D, Pereira AG, Lever N, Ramanathan T, Smaill BH, Montgomery JM. Electrophysiology and 3D-imaging reveal properties of human intracardiac neurons and increased excitability with atrial fibrillation. J Physiol 2024. [PMID: 38687681 DOI: 10.1113/jp286278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 03/22/2024] [Indexed: 05/02/2024] Open
Abstract
Altered autonomic input to the heart plays a major role in atrial fibrillation (AF). Autonomic neurons termed ganglionated plexi (GP) are clustered on the heart surface to provide the last point of neural control of cardiac function. To date the properties of GP neurons in humans are unknown. Here we have addressed this knowledge gap in human GP neuron structure and physiology in patients with and without AF. Human right atrial GP neurons embedded in epicardial adipose tissue were excised during open heart surgery performed on both non-AF and AF patients and then characterised physiologically by whole cell patch clamp techniques. Structural analysis was also performed after fixation at both the single cell and at the entire GP levels via three-dimensional confocal imaging. Human GP neurons were found to exhibit unique properties and structural complexity with branched neurite outgrowth. Significant differences in excitability were revealed between AF and non-AF GP neurons as measured by lower current to induce action potential firing, a reduced occurrence of low action potential firing rates, decreased accommodation and increased synaptic density. Visualisation of entire GPs showed almost all neurons are cholinergic with a small proportion of noradrenergic and dual phenotype neurons. Phenotypic distribution differences occurred with AF including decreased cholinergic and dual phenotype neurons, and increased noradrenergic neurons. These data show both functional and structural differences occur between GP neurons from patients with and without AF, highlighting that cellular plasticity occurs in neural input to the heart that could alter autonomic influence on atrial function. KEY POINTS: The autonomic nervous system plays a critical role in regulating heart rhythm and the initiation of AF; however, the structural and functional properties of human autonomic neurons in the autonomic ganglionated plexi (GP) remain unknown. Here we perform the first whole cell patch clamp electrophysiological and large tissue confocal imaging analysis of these neurons from patients with and without AF. Our data show human GP neurons are functionally and structurally complex. Measurements of action potential kinetics show higher excitability in GP neurons from AF patients as measured by lower current to induce action potential firing, reduced low firing action potential rates, and decreased action potential accommodation. Confocal imaging shows increased synaptic density and noradrenergic phenotypes in patients with AF. Both functional and structural differences occur in GP neurons from patients with AF that could alter autonomic influence on atrial rhythm.
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Affiliation(s)
- J L Ashton
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - B Prince
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - G Sands
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - L Argent
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - M Anderson
- Cardiothoracic Surgical Unit, Auckland City Hospital, Auckland, New Zealand
| | - J E G Smith
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - A Tedoldi
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - A Ahmad
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
| | - D Baddeley
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - A G Pereira
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - N Lever
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
- Department of Cardiology, Auckland City Hospital, Auckland, New Zealand
| | - T Ramanathan
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
- Cardiothoracic Surgical Unit, Auckland City Hospital, Auckland, New Zealand
| | - B H Smaill
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Johanna M Montgomery
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Manaaki Manawa Centre for Heart Research, University of Auckland and Pūtahi Manawa Centre of Research Excellence, Auckland, New Zealand
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3
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Rajendran PS, Hadaya J, Khalsa SS, Yu C, Chang R, Shivkumar K. The vagus nerve in cardiovascular physiology and pathophysiology: From evolutionary insights to clinical medicine. Semin Cell Dev Biol 2024; 156:190-200. [PMID: 36641366 PMCID: PMC10336178 DOI: 10.1016/j.semcdb.2023.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/01/2023] [Accepted: 01/03/2023] [Indexed: 01/13/2023]
Abstract
The parasympathetic nervous system via the vagus nerve exerts profound influence over the heart. Together with the sympathetic nervous system, the parasympathetic nervous system is responsible for fine-tuned regulation of all aspects of cardiovascular function, including heart rate, rhythm, contractility, and blood pressure. In this review, we highlight vagal efferent and afferent innervation of the heart, with a focus on insights from comparative biology and advances in understanding the molecular and genetic diversity of vagal neurons, as well as interoception, parasympathetic dysfunction in heart disease, and the therapeutic potential of targeting the parasympathetic nervous system in cardiovascular disease.
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Affiliation(s)
| | - Joseph Hadaya
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; UCLA Molecular, Cellular, and Integrative Physiology Program, Los Angeles, CA, USA
| | - Sahib S Khalsa
- Laureate Institute for Brain Research, Tulsa, Ok, USA; Oxley College of Health Sciences, University of Tulsa, Tulsa, Ok, USA
| | - Chuyue Yu
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Rui Chang
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Kalyanam Shivkumar
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; UCLA Molecular, Cellular, and Integrative Physiology Program, Los Angeles, CA, USA.
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4
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Giannino G, Braia V, Griffith Brookles C, Giacobbe F, D'Ascenzo F, Angelini F, Saglietto A, De Ferrari GM, Dusi V. The Intrinsic Cardiac Nervous System: From Pathophysiology to Therapeutic Implications. BIOLOGY 2024; 13:105. [PMID: 38392323 PMCID: PMC10887082 DOI: 10.3390/biology13020105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/24/2024]
Abstract
The cardiac autonomic nervous system (CANS) plays a pivotal role in cardiac homeostasis as well as in cardiac pathology. The first level of cardiac autonomic control, the intrinsic cardiac nervous system (ICNS), is located within the epicardial fat pads and is physically organized in ganglionated plexi (GPs). The ICNS system does not only contain parasympathetic cardiac efferent neurons, as long believed, but also afferent neurons and local circuit neurons. Thanks to its high degree of connectivity, combined with neuronal plasticity and memory capacity, the ICNS allows for a beat-to-beat control of all cardiac functions and responses as well as integration with extracardiac and higher centers for longer-term cardiovascular reflexes. The present review provides a detailed overview of the current knowledge of the bidirectional connection between the ICNS and the most studied cardiac pathologies/conditions (myocardial infarction, heart failure, arrhythmias and heart transplant) and the potential therapeutic implications. Indeed, GP modulation with efferent activity inhibition, differently achieved, has been studied for atrial fibrillation and functional bradyarrhythmias, while GP modulation with efferent activity stimulation has been evaluated for myocardial infarction, heart failure and ventricular arrhythmias. Electrical therapy has the unique potential to allow for both kinds of ICNS modulation while preserving the anatomical integrity of the system.
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Affiliation(s)
- Giuseppe Giannino
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Valentina Braia
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Carola Griffith Brookles
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Federico Giacobbe
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Fabrizio D'Ascenzo
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Filippo Angelini
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Andrea Saglietto
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Gaetano Maria De Ferrari
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
| | - Veronica Dusi
- Cardiology, Department of Medical Sciences, University of Turin, 10124 Torino, Italy
- Division of Cardiology, Cardiovascular and Thoracic Department, 'Città della Salute e della Scienza' Hospital, 10126 Torino, Italy
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5
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Chin SH, Allen E, Brack KE, Ng GA. Autonomic neuro-cardiac profile of electrical, structural and neuronal remodeling in myocardial infarction-induced heart failure. JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY PLUS 2023; 5:100044. [PMID: 37745157 PMCID: PMC10512199 DOI: 10.1016/j.jmccpl.2023.100044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 07/25/2023] [Accepted: 08/16/2023] [Indexed: 09/26/2023]
Abstract
Aims Heart failure is a clinical syndrome typified by abnormal autonomic tone, impaired ventricular function, and increased arrhythmic vulnerability. This study aims to examine electrophysiological, structural and neuronal remodeling following myocardial infarction in a rabbit heart failure model to establish its neuro-cardiac profile. Methods and results Weight-matched adult male New Zealand White rabbits (3.2 ± 0.1 kg, n = 25) were randomized to have coronary ligation surgeries (HF group, n = 13) or sham procedures (SHM group, n = 12). Transthoracic echocardiography was performed six weeks post-operatively. On week 8, dual-innervated Langendorff-perfused heart preparations were set up for terminal experiments. Seventeen hearts (HF group, n = 10) underwent ex-vivo cardiac MRI. Twenty-two hearts (HF group, n = 7) were examined histologically. Electrical remodeling and abnormal autonomic profile were evident in HF rabbits with exaggerated sympathetic and attenuated vagal effect on ventricular fibrillation threshold, ventricular refractoriness and restitution curves, in addition to increased spatial restitution dispersion. Histologically, there was significant neuronal enlargement at the heart hila and conus arteriosus in HF. Structural remodeling was characterized by quantifiable myocardial scarring, enlarged left ventricles, altered ventricular geometry and impaired contractility. Conclusion In an infarct-induced rabbit heart failure model, extensive structural, neuronal and electrophysiological remodeling in conjunction with abnormal autonomic profile provide substrates for ventricular arrhythmias.
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Affiliation(s)
- Shui Hao Chin
- Cardiology group, Department of Cardiovascular Sciences, University of Leicester, UK
- University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Emily Allen
- Cardiology group, Department of Cardiovascular Sciences, University of Leicester, UK
| | - Kieran E. Brack
- Cardiology group, Department of Cardiovascular Sciences, University of Leicester, UK
| | - G. André Ng
- Cardiology group, Department of Cardiovascular Sciences, University of Leicester, UK
- University Hospitals of Leicester NHS Trust, Leicester, UK
- NIHR Leicester Cardiovascular Biomedical Research Unit, Leicester, UK
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6
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Mircea AA, Mori S, Ajijola OA, Khakpour H. Sinus Arrest during Radiofrequency Ablation from the Infero-septal Process of the Left Ventricle: Proposed Mechanisms of an Uncommon Finding. HeartRhythm Case Rep 2023. [DOI: 10.1016/j.hrcr.2023.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
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7
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Elia A, Fossati S. Autonomic nervous system and cardiac neuro-signaling pathway modulation in cardiovascular disorders and Alzheimer's disease. Front Physiol 2023; 14:1060666. [PMID: 36798942 PMCID: PMC9926972 DOI: 10.3389/fphys.2023.1060666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 01/19/2023] [Indexed: 01/31/2023] Open
Abstract
The heart is a functional syncytium controlled by a delicate and sophisticated balance ensured by the tight coordination of its several cell subpopulations. Accordingly, cardiomyocytes together with the surrounding microenvironment participate in the heart tissue homeostasis. In the right atrium, the sinoatrial nodal cells regulate the cardiac impulse propagation through cardiomyocytes, thus ensuring the maintenance of the electric network in the heart tissue. Notably, the central nervous system (CNS) modulates the cardiac rhythm through the two limbs of the autonomic nervous system (ANS): the parasympathetic and sympathetic compartments. The autonomic nervous system exerts non-voluntary effects on different peripheral organs. The main neuromodulator of the Sympathetic Nervous System (SNS) is norepinephrine, while the principal neurotransmitter of the Parasympathetic Nervous System (PNS) is acetylcholine. Through these two main neurohormones, the ANS can gradually regulate cardiac, vascular, visceral, and glandular functions by turning on one of its two branches (adrenergic and/or cholinergic), which exert opposite effects on targeted organs. Besides these neuromodulators, the cardiac nervous system is ruled by specific neuropeptides (neurotrophic factors) that help to preserve innervation homeostasis through the myocardial layers (from epicardium to endocardium). Interestingly, the dysregulation of this neuro-signaling pathway may expose the cardiac tissue to severe disorders of different etiology and nature. Specifically, a maladaptive remodeling of the cardiac nervous system may culminate in a progressive loss of neurotrophins, thus leading to severe myocardial denervation, as observed in different cardiometabolic and neurodegenerative diseases (myocardial infarction, heart failure, Alzheimer's disease). This review analyzes the current knowledge on the pathophysiological processes involved in cardiac nervous system impairment from the perspectives of both cardiac disorders and a widely diffused and devastating neurodegenerative disorder, Alzheimer's disease, proposing a relationship between neurodegeneration, loss of neurotrophic factors, and cardiac nervous system impairment. This overview is conducive to a more comprehensive understanding of the process of cardiac neuro-signaling dysfunction, while bringing to light potential therapeutic scenarios to correct or delay the adverse cardiovascular remodeling, thus improving the cardiac prognosis and quality of life in patients with heart or neurodegenerative disorders.
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8
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Scridon A. Autonomic imbalance and atrial ectopic activity-a pathophysiological and clinical view. Front Physiol 2022; 13:1058427. [PMID: 36531175 PMCID: PMC9755506 DOI: 10.3389/fphys.2022.1058427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/22/2022] [Indexed: 09/29/2023] Open
Abstract
The heart is one of the most richly innervated organs and the impact of the complex cardiac autonomic network on atrial electrophysiology and arrhythmogenesis, including on atrial ectopy, is widely recognized. The aim of this review is to discuss the main mechanisms involved in atrial ectopic activity. An overview of the anatomic and physiological aspects of the cardiac autonomic nervous system is provided as well as a discussion of the main pathophysiological pathways linking autonomic imbalance and atrial ectopic activity. The most relevant data on cardiac neuromodulation strategies are emphasized. Unanswered questions and hotspots for future research are also identified.
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Affiliation(s)
- Alina Scridon
- Physiology Department, Center for Advanced Medical and Pharmaceutical Research, University of Medicine, Pharmacy, Science and Technology “George Emil Palade” of Târgu Mureș, Târgu Mureș, Romania
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9
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Tompkins JD, Buckley U, Salavatian S, Shivkumar K, Ardell JL. Vagally-mediated heart block after myocardial infarction associated with plasticity of epicardial neurons controlling the atrioventricular node. Front Synaptic Neurosci 2022; 14:960458. [PMID: 36147731 PMCID: PMC9488518 DOI: 10.3389/fnsyn.2022.960458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 07/26/2022] [Indexed: 11/25/2022] Open
Abstract
Imbalances in the opposing actions of sympathetic and parasympathetic nerves controlling the heart enhance risk for arrhythmia and sudden cardiac death after myocardial infarction (MI). Plasticity in peripheral neuron function may underlie the observed changes in cardiomotor nerve activity. We studied vagal control of the heart in pigs after chronic infarction of the left ventricle. Stimulation of the cervical vagus nerve produced greater bradycardic responses 8-weeks after MI. Recordings of epicardial electrocardiograms demonstrate increased severity and duration of atrioventricular (AV) block in MI-pigs during 20 Hz vagal stimulation. Intracellular voltage recordings from isolated neurons of the inferior vena cava-inferior left atrium (IVC-ILA) ganglionated plexus, a cluster of epicardial neurons receiving innervation from the vagus known to regulate the AV node, were used to assess plasticity of membrane and synaptic physiology of intrinsic cardiac neurons (ICNs) after MI. Changes to both passive and active membrane properties were observed, including more negative resting membrane potentials and greater input resistances in MI-pig ICNs, concomitant with a depression of neuronal excitability. Immunoreactivity to pituitary adenylate cyclase-activating polypeptide (PACAP), a cardiotropic peptide known to modulate cardiac neuron excitability, was localized to perineuronal varicosities surrounding pig IVC-ILA neurons. Exogenous application of PACAP increased excitability of control but not MI-ICNs. Stimulation (20 Hz) of interganglionic nerves in the ex vivo whole-mount preparations elicited slow excitatory postsynaptic potentials (sEPSPs) which persisted in hexamethonium (500 μM), but were blocked by atropine (1 μM), indicating muscarinic receptor-mediated inhibition of M-current. Extracellular application of 1 mM BaCl2 to inhibit M-current increased neuronal excitability. The muscarine-sensitive sEPSPs were observed more frequently and were of larger amplitude in IVC-ILA neurons from MI animals. In conclusion, we suggest the increased probability of muscarinic sEPSPs play a role in the potentiation of the vagus nerve mediated-slowing of AV nodal conduction following chronic MI. We identify both a novel role of a muscarinic sensitive current in the regulation of synaptic strength at ICNs projecting to the AV node, and demonstrate changes to both intrinsic plasticity and synaptic plasticity of IVC-ILA neurons which may contribute to greater risk for heart block and sudden cardiac death after MI.
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10
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Kharbanda RK, van der Does WFB, van Staveren LN, Taverne YJHJ, Bogers AJJC, de Groot NMS. Vagus Nerve Stimulation and Atrial Fibrillation: Revealing the Paradox. Neuromodulation 2022; 25:356-365. [PMID: 35190246 DOI: 10.1016/j.neurom.2022.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 12/28/2021] [Accepted: 01/04/2022] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND OBJECTIVE The cardiac autonomic nervous system (CANS) plays an important role in the pathophysiology of atrial fibrillation (AF). Cardiovascular disease can cause an imbalance within the CANS, which may contribute to the initiation and maintenance of AF. Increased understanding of neuromodulation of the CANS has resulted in novel emerging therapies to treat cardiac arrhythmias by targeting different circuits of the CANS. Regarding AF, neuromodulation therapies targeting the vagus nerve have yielded promising outcomes. However, targeting the vagus nerve can be both pro-arrhythmogenic and anti-arrhythmogenic. Currently, these opposing effects of vagus nerve stimulation (VNS) have not been clearly described. The aim of this review is therefore to discuss both pro-arrhythmogenic and anti-arrhythmogenic effects of VNS and recent advances in clinical practice and to provide future perspectives for VNS to treat AF. MATERIALS AND METHODS A comprehensive review of current literature on VNS and its pro-arrhythmogenic and anti-arrhythmogenic effects on atrial tissue was performed. Both experimental and clinical studies are reviewed and discussed separately. RESULTS VNS exhibits both pro-arrhythmogenic and anti-arrhythmogenic effects. The anatomical site and stimulation settings during VNS play a crucial role in determining its effect on cardiac electrophysiology. Since the last decade, there is accumulating evidence from experimental studies and randomized clinical studies that low-level VNS (LLVNS), below the bradycardia threshold, is an effective treatment for AF. CONCLUSION LLVNS is a promising novel therapeutic modality to treat AF and further research will further elucidate the underlying anti-arrhythmogenic mechanisms, optimal stimulation settings, and site to apply LLVNS.
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Affiliation(s)
- Rohit K Kharbanda
- Department of Cardiology, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Cardiothoracic Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | | | - Yannick J H J Taverne
- Department of Cardiothoracic Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Ad J J C Bogers
- Department of Cardiothoracic Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
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11
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Stress-related dysautonomias and neurocardiology-based treatment approaches. Auton Neurosci 2022; 239:102944. [DOI: 10.1016/j.autneu.2022.102944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 10/13/2021] [Accepted: 01/16/2022] [Indexed: 11/21/2022]
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12
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Leung C, Robbins S, Moss A, Heal M, Osanlouy M, Christie R, Farahani N, Monteith C, Chen J, Hunter P, Tappan S, Vadigepalli R, Cheng Z(J, Schwaber JS. 3D single cell scale anatomical map of sex-dependent variability of the rat intrinsic cardiac nervous system. iScience 2021; 24:102795. [PMID: 34355144 PMCID: PMC8324857 DOI: 10.1016/j.isci.2021.102795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 05/05/2021] [Accepted: 06/24/2021] [Indexed: 02/01/2023] Open
Abstract
We developed and analyzed a single cell scale anatomical map of the rat intrinsic cardiac nervous system (ICNS) across four male and three female hearts. We find the ICNS has a reliable structural organizational plan across individuals that provide the foundation for further analyses of the ICNS in cardiac function and disease. The distribution of the ICNS was evaluated by 3D visualization and data-driven clustering. The pattern, distribution, and clustering of ICNS neurons across all male and female rat hearts is highly conserved, demonstrating a coherent organizational plan where distinct clusters of neurons are consistently localized. Female hearts had fewer neurons, lower packing density, and slightly reduced distribution, but with identical localization. We registered the anatomical data from each heart to a geometric scaffold, normalizing their 3D coordinates for standardization of common anatomical planes and providing a path where multiple experimental results and data types can be integrated and compared.
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Affiliation(s)
- Clara Leung
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Shaina Robbins
- Daniel Baugh Institute of Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Alison Moss
- Daniel Baugh Institute of Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | | | - Mahyar Osanlouy
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Richard Christie
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | | | - Jin Chen
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Peter Hunter
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | - Rajanikanth Vadigepalli
- Daniel Baugh Institute of Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Zixi (Jack) Cheng
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - James S. Schwaber
- Daniel Baugh Institute of Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
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13
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Hanna P, Buch E, Stavrakis S, Meyer C, Tompkins JD, Ardell JL, Shivkumar K. Neuroscientific therapies for atrial fibrillation. Cardiovasc Res 2021; 117:1732-1745. [PMID: 33989382 PMCID: PMC8208752 DOI: 10.1093/cvr/cvab172] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 05/13/2021] [Indexed: 02/06/2023] Open
Abstract
The cardiac autonomic nervous system (ANS) plays an integral role in normal cardiac physiology as well as in disease states that cause cardiac arrhythmias. The cardiac ANS, comprised of a complex neural hierarchy in a nested series of interacting feedback loops, regulates atrial electrophysiology and is itself susceptible to remodelling by atrial rhythm. In light of the challenges of treating atrial fibrillation (AF) with conventional pharmacologic and myoablative techniques, increasingly interest has begun to focus on targeting the cardiac neuraxis for AF. Strong evidence from animal models and clinical patients demonstrates that parasympathetic and sympathetic activity within this neuraxis may trigger AF, and the ANS may either induce atrial remodelling or undergo remodelling itself to serve as a substrate for AF. Multiple nexus points within the cardiac neuraxis are therapeutic targets, and neuroablative and neuromodulatory therapies for AF include ganglionated plexus ablation, epicardial botulinum toxin injection, vagal nerve (tragus) stimulation, renal denervation, stellate ganglion block/resection, baroreceptor activation therapy, and spinal cord stimulation. Pre-clinical and clinical studies on these modalities have had promising results and are reviewed here.
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Affiliation(s)
- Peter Hanna
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Neurocardiology Research Program of Excellence, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Molecular, Cellular & Integrative Physiology Program, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
| | - Eric Buch
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
| | - Stavros Stavrakis
- Heart Rhythm Institute, University of Oklahoma Health Sciences Center, 1100 N Lindsay Ave, Oklahoma City, OK 73104, USA
| | - Christian Meyer
- Division of Cardiology, cardiac Neuro- and Electrophysiology Research Consortium (cNEP), EVK Düsseldorf, Teaching Hospital University of Düsseldorf, Kirchfeldstraße 40, 40217 Düsseldorf, Germany
- Institute of Neural and Sensory Physiology, cardiac Neuro- and Electrophysiology Research Consortium (cNEP), University of Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - John D Tompkins
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Neurocardiology Research Program of Excellence, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
| | - Jeffrey L Ardell
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Neurocardiology Research Program of Excellence, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Molecular, Cellular & Integrative Physiology Program, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
| | - Kalyanam Shivkumar
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Neurocardiology Research Program of Excellence, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
- Molecular, Cellular & Integrative Physiology Program, David Geffen School of Medicine, UCLA, 100 Medical Plaza, Suite 660, Los Angeles, CA 90095, USA
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14
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Hanna P, Dacey MJ, Brennan J, Moss A, Robbins S, Achanta S, Biscola NP, Swid MA, Rajendran PS, Mori S, Hadaya JE, Smith EH, Peirce SG, Chen J, Havton LA, Cheng Z(J, Vadigepalli R, Schwaber J, Lux RL, Efimov I, Tompkins JD, Hoover DB, Ardell JL, Shivkumar K. Innervation and Neuronal Control of the Mammalian Sinoatrial Node a Comprehensive Atlas. Circ Res 2021; 128:1279-1296. [PMID: 33629877 PMCID: PMC8284939 DOI: 10.1161/circresaha.120.318458] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Peter Hanna
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
- UCLA Molecular, Cellular & Integrative Physiology Program, UCLA
| | - Michael J. Dacey
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
- UCLA Molecular, Cellular & Integrative Physiology Program, UCLA
| | - Jaclyn Brennan
- Bioengineering, George Washington University, Washington, DC
| | - Alison Moss
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | - Shaina Robbins
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | - Sirisha Achanta
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | | | - Mohammed A. Swid
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | - Pradeep S. Rajendran
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | - Shumpei Mori
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | - Joseph E. Hadaya
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | | | | | - Jin Chen
- University of Central Florida, Burnett School of Biomedical Sciences, College of Medicine, Orlando, FL
| | - Leif A. Havton
- Neurology, Icahn School of Medicine at Mount Sinai, New York City, NY
- Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY
- VA RR&D National Center of Excellence for the Medical Consequences of Spinal and; Cord Injury and Neurology Service, James J. Peters Veterans Administration Medical Center, Bronx, NY
| | - Zixi (Jack) Cheng
- University of Central Florida, Burnett School of Biomedical Sciences, College of Medicine, Orlando, FL
| | - Rajanikanth Vadigepalli
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | - James Schwaber
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | - Robert L. Lux
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | - Igor Efimov
- Bioengineering, George Washington University, Washington, DC
| | - John D. Tompkins
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
| | - Donald B. Hoover
- Biomedical Sciences
- Center of Excellence in Inflammation, Infectious Disease and Immunity, James H. Quillen College of Medicine, East Tennessee State University
| | - Jeffrey L. Ardell
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
- UCLA Molecular, Cellular & Integrative Physiology Program, UCLA
| | - Kalyanam Shivkumar
- University of California Los Angeles (UCLA) Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, Department of Medicine
- UCLA Molecular, Cellular & Integrative Physiology Program, UCLA
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15
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Hadaya J, Ardell JL. Autonomic Modulation for Cardiovascular Disease. Front Physiol 2020; 11:617459. [PMID: 33414727 PMCID: PMC7783451 DOI: 10.3389/fphys.2020.617459] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 11/25/2020] [Indexed: 12/11/2022] Open
Abstract
Dysfunction of the autonomic nervous system has been implicated in the pathogenesis of cardiovascular disease, including congestive heart failure and cardiac arrhythmias. Despite advances in the medical and surgical management of these entities, progression of disease persists as does the risk for sudden cardiac death. With improved knowledge of the dynamic relationships between the nervous system and heart, neuromodulatory techniques such as cardiac sympathetic denervation and vagal nerve stimulation (VNS) have emerged as possible therapeutic approaches for the management of these disorders. In this review, we present the structure and function of the cardiac nervous system and the remodeling that occurs in disease states, emphasizing the concept of increased sympathoexcitation and reduced parasympathetic tone. We review preclinical evidence for vagal nerve stimulation, and early results of clinical trials in the setting of congestive heart failure. Vagal nerve stimulation, and other neuromodulatory techniques, may improve the management of cardiovascular disorders, and warrant further study.
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Affiliation(s)
- Joseph Hadaya
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, United States.,UCLA Neurocardiology Research Program of Excellence, UCLA, Los Angeles, CA, United States.,Molecular, Cellular, and Integrative Physiology Program, UCLA, Los Angeles, CA, United States
| | - Jeffrey L Ardell
- University of California, Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, United States.,UCLA Neurocardiology Research Program of Excellence, UCLA, Los Angeles, CA, United States
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16
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Achanta S, Gorky J, Leung C, Moss A, Robbins S, Eisenman L, Chen J, Tappan S, Heal M, Farahani N, Huffman T, England S, Cheng ZJ, Vadigepalli R, Schwaber JS. A Comprehensive Integrated Anatomical and Molecular Atlas of Rat Intrinsic Cardiac Nervous System. iScience 2020; 23:101140. [PMID: 32460006 PMCID: PMC7327996 DOI: 10.1016/j.isci.2020.101140] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/11/2020] [Accepted: 05/01/2020] [Indexed: 12/21/2022] Open
Abstract
We have developed and integrated several technologies including whole-organ imaging and software development to support an initial precise 3D neuroanatomical mapping and molecular phenotyping of the intracardiac nervous system (ICN). While qualitative and gross anatomical descriptions of the anatomy of the ICN have each been pursued, we here bring forth a comprehensive atlas of the entire rat ICN at single-cell resolution. Our work precisely integrates anatomical and molecular data in the 3D digitally reconstructed whole heart with resolution at the micron scale. We now display the full extent and the position of neuronal clusters on the base and posterior left atrium of the rat heart, and the distribution of molecular phenotypes that are defined along the base-to-apex axis, which had not been previously described. The development of these approaches needed for this work has produced method pipelines that provide the means for mapping other organs. Comprehensive single-neuron-scale mapping of the intrinsic cardiac nervous system Whole-organ high-throughput imaging and reconstruction at a cellular resolution 3D anatomical framework for spatially tracked single-neuron molecular phenotypes Integrated histology, neuron mapping, and molecular profiles for 3D organ reconstruction
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Affiliation(s)
- Sirisha Achanta
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Jonathan Gorky
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Clara Leung
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Alison Moss
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Shaina Robbins
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Leonard Eisenman
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Jin Chen
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | | | | | | | | | | | - Zixi Jack Cheng
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA.
| | - Rajanikanth Vadigepalli
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA.
| | - James S Schwaber
- Daniel Baugh Institute for Functional Genomics/Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA.
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17
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Jungen C, Scherschel K, Flenner F, Jee H, Rajendran P, De Jong KA, Nikolaev V, Meyer C, Ardell JL, Tompkins JD. Increased arrhythmia susceptibility in type 2 diabetic mice related to dysregulation of ventricular sympathetic innervation. Am J Physiol Heart Circ Physiol 2019; 317:H1328-H1341. [PMID: 31625779 DOI: 10.1152/ajpheart.00249.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Patients with type 2 diabetes mellitus (T2DM) have a greater risk of developing life-threatening cardiac arrhythmias. Because the underlying mechanisms and potential influence of diabetic autonomic neuropathy are not well understood, we aimed to assess the relevance of a dysregulation in cardiac autonomic tone. Ventricular arrhythmia susceptibility was increased in Langendorff-perfused hearts isolated from mice with T2DM (db/db). Membrane properties and synaptic transmission were similar at cardiac postganglionic parasympathetic neurons from diabetic and control mice; however, a greater asynchronous neurotransmitter release was present at sympathetic postganglionic neurons from the stellate ganglia of db/db mice. Western blot analysis showed a reduction of tyrosine hydroxylase (TH) from the ventricles of db/db mice, which was confirmed with confocal imaging as a heterogeneous loss of TH-immunoreactivity from the left ventricular wall but not the apex. In vivo stimulation of cardiac parasympathetic (vagus) or cardiac sympathetic (stellate ganglion) nerves induced similar changes in heart rate in control and db/db mice, and the kinetics of pacing-induced Ca2+ transients (recorded from isolated cardiomyocytes) were similar in control and db/db cells. Antagonism of cardiac muscarinic receptors did not affect the frequency or severity of arrhythmias in db/db mice, but sympathetic blockade with propranolol completely inhibited arrhythmogenicity. Collectively, these findings suggest that the increased ventricular arrhythmia susceptibility of type 2 diabetic mouse hearts is due to dysregulation of the sympathetic ventricular control.NEW & NOTEWORTHY Patients with type 2 diabetes mellitus have greater risk of suffering from sudden cardiac death. We found that the increased ventricular arrhythmia susceptibility in type 2 diabetic mouse hearts is due to cardiac sympathetic dysfunction. Sympathetic dysregulation is indicated by an increased asynchronous release at stellate ganglia, a heterogeneous loss of tyrosine hydroxylase from the ventricular wall but not apex, and inhibition of ventricular arrhythmias in db/db mice after β-sympathetic blockade.
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Affiliation(s)
- Christiane Jungen
- Department of Cardiology-Electrophysiology, cNEP, cardiac Neuro- and Electrophysiology research group, University Heart Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Katharina Scherschel
- Department of Cardiology-Electrophysiology, cNEP, cardiac Neuro- and Electrophysiology research group, University Heart Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Frederik Flenner
- DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany.,Department of Experimental Pharmacology and Toxicology, Cardiovascular Research Centre, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Haesung Jee
- University of California, Los Angeles Cardiac Arrhythmia Center, Neurocardiology Research Program of Excellence, Department of Medicine-Cardiology, Los Angeles, California
| | - Pradeep Rajendran
- University of California, Los Angeles Cardiac Arrhythmia Center, Neurocardiology Research Program of Excellence, Department of Medicine-Cardiology, Los Angeles, California
| | - Kirstie A De Jong
- DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany.,Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, University of Hamburg, Germany
| | - Viacheslav Nikolaev
- DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany.,Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, University of Hamburg, Germany
| | - Christian Meyer
- Department of Cardiology-Electrophysiology, cNEP, cardiac Neuro- and Electrophysiology research group, University Heart Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Jeffrey L Ardell
- University of California, Los Angeles Cardiac Arrhythmia Center, Neurocardiology Research Program of Excellence, Department of Medicine-Cardiology, Los Angeles, California
| | - John D Tompkins
- University of California, Los Angeles Cardiac Arrhythmia Center, Neurocardiology Research Program of Excellence, Department of Medicine-Cardiology, Los Angeles, California
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18
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Allen E, Coote JH, Grubb BD, Batten TFC, Pauza DH, Ng GA, Brack KE. Electrophysiological effects of nicotinic and electrical stimulation of intrinsic cardiac ganglia in the absence of extrinsic autonomic nerves in the rabbit heart. Heart Rhythm 2018; 15:1698-1707. [PMID: 29800749 PMCID: PMC6207532 DOI: 10.1016/j.hrthm.2018.05.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Indexed: 11/18/2022]
Abstract
Background The intrinsic cardiac nervous system is a rich network of cardiac nerves that converge to form distinct ganglia and extend across the heart and is capable of influencing cardiac function. Objective The goals of this study were to provide a complete picture of the neurotransmitter/neuromodulator profile of the rabbit intrinsic cardiac nervous system and to determine the influence of spatially divergent ganglia on cardiac electrophysiology. Methods Nicotinic or electrical stimulation was applied at discrete sites of the intrinsic cardiac nerve plexus in the Langendorff-perfused rabbit heart. Functional effects on sinus rate and atrioventricular conduction were measured. Immunohistochemistry for choline acetyltransferase (ChAT), tyrosine hydroxylase, and/or neuronal nitric oxide synthase (nNOS) was performed using whole mount preparations. Results Stimulation within all ganglia produced either bradycardia, tachycardia, or a biphasic brady-tachycardia. Electrical stimulation of the right atrial and right neuronal cluster regions produced the largest chronotropic responses. Significant prolongation of atrioventricular conduction was predominant at the pulmonary vein-caudal vein region. Neurons immunoreactive (IR) only for ChAT, tyrosine hydroxylase, or nNOS were consistently located within the limits of the hilum and at the roots of the right cranial and right pulmonary veins. ChAT-IR neurons were most abundant (1946 ± 668 neurons). Neurons IR only for nNOS were distributed within ganglia. Conclusion Stimulation of intrinsic ganglia, shown to be of phenotypic complexity but predominantly of cholinergic nature, indicates that clusters of neurons are capable of independent selective effects on cardiac electrophysiology, therefore providing a potential therapeutic target for the prevention and treatment of cardiac disease.
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Affiliation(s)
- Emily Allen
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, United Kingdom; NIHR Leicester BRC, Glenfield Hospital, Leicester, United Kingdom
| | - John H Coote
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, United Kingdom
| | - Blair D Grubb
- Institute of Life and Human Sciences, University of Liverpool, Liverpool, United Kingdom
| | | | - Dainius H Pauza
- Institute of Anatomy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - G André Ng
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, United Kingdom; NIHR Leicester BRC, Glenfield Hospital, Leicester, United Kingdom.
| | - Kieran E Brack
- Department of Cardiovascular Sciences, University of Leicester, Glenfield Hospital, Leicester, United Kingdom; NIHR Leicester BRC, Glenfield Hospital, Leicester, United Kingdom
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19
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Kember G, Ardell JL, Shivkumar K, Armour JA. Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control. PLoS One 2017; 12:e0180194. [PMID: 28692680 PMCID: PMC5503241 DOI: 10.1371/journal.pone.0180194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 06/12/2017] [Indexed: 12/20/2022] Open
Abstract
The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.
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Affiliation(s)
- Guy Kember
- Dept. of Engineering Mathematics and Internetworking/Faculty of Engineering/Dalhousie University, Halifax, NS, Canada
- * E-mail:
| | - Jeffrey L. Ardell
- David Geffen School of Medicine/Cardiac Arrhythmia Center, University of California – Los Angeles (UCLA), Los Angeles, CA, United States of America
| | - Kalyanam Shivkumar
- David Geffen School of Medicine/Cardiac Arrhythmia Center, University of California – Los Angeles (UCLA), Los Angeles, CA, United States of America
| | - J. Andrew Armour
- David Geffen School of Medicine/Cardiac Arrhythmia Center, University of California – Los Angeles (UCLA), Los Angeles, CA, United States of America
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20
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Kingma JG, Simard D, Rouleau JR. Influence of cardiac nerve status on cardiovascular regulation and cardioprotection. World J Cardiol 2017; 9:508-520. [PMID: 28706586 PMCID: PMC5491468 DOI: 10.4330/wjc.v9.i6.508] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 03/22/2017] [Accepted: 04/24/2017] [Indexed: 02/07/2023] Open
Abstract
Neural elements of the intrinsic cardiac nervous system transduce sensory inputs from the heart, blood vessels and other organs to ensure adequate cardiac function on a beat-to-beat basis. This inter-organ crosstalk is critical for normal function of the heart and other organs; derangements within the nervous system hierarchy contribute to pathogenesis of organ dysfunction. The role of intact cardiac nerves in development of, as well as protection against, ischemic injury is of current interest since it may involve recruitment of intrinsic cardiac ganglia. For instance, ischemic conditioning, a novel protection strategy against organ injury, and in particular remote conditioning, is likely mediated by activation of neural pathways or by endogenous cytoprotective blood-borne substances that stimulate different signalling pathways. This discovery reinforces the concept that inter-organ communication, and maintenance thereof, is key. As such, greater understanding of mechanisms and elucidation of treatment strategies is imperative to improve clinical outcomes particularly in patients with comorbidities. For instance, autonomic imbalance between sympathetic and parasympathetic nervous system regulation can initiate cardiovascular autonomic neuropathy that compromises cardiac stability and function. Neuromodulation therapies that directly target the intrinsic cardiac nervous system or other elements of the nervous system hierarchy are currently being investigated for treatment of different maladies in animal and human studies.
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21
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Hamon D, Rajendran PS, Chui RW, Ajijola OA, Irie T, Talebi R, Salavatian S, Vaseghi M, Bradfield JS, Armour JA, Ardell JL, Shivkumar K. Premature Ventricular Contraction Coupling Interval Variability Destabilizes Cardiac Neuronal and Electrophysiological Control: Insights From Simultaneous Cardioneural Mapping. Circ Arrhythm Electrophysiol 2017; 10:CIRCEP.116.004937. [PMID: 28408652 DOI: 10.1161/circep.116.004937] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 02/15/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Variability in premature ventricular contraction (PVC) coupling interval (CI) increases the risk of cardiomyopathy and sudden death. The autonomic nervous system regulates cardiac electrical and mechanical indices, and its dysregulation plays an important role in cardiac disease pathogenesis. The impact of PVCs on the intrinsic cardiac nervous system, a neural network on the heart, remains unknown. The objective was to determine the effect of PVCs and CI on intrinsic cardiac nervous system function in generating cardiac neuronal and electric instability using a novel cardioneural mapping approach. METHODS AND RESULTS In a porcine model (n=8), neuronal activity was recorded from a ventricular ganglion using a microelectrode array, and cardiac electrophysiological mapping was performed. Neurons were functionally classified based on their response to afferent and efferent cardiovascular stimuli, with neurons that responded to both defined as convergent (local reflex processors). Dynamic changes in neuronal activity were then evaluated in response to right ventricular outflow tract PVCs with fixed short, fixed long, and variable CI. PVC delivery elicited a greater neuronal response than all other stimuli (P<0.001). Compared with fixed short and long CI, PVCs with variable CI had a greater impact on neuronal response (P<0.05 versus short CI), particularly on convergent neurons (P<0.05), as well as neurons receiving sympathetic (P<0.05) and parasympathetic input (P<0.05). The greatest cardiac electric instability was also observed after variable (short) CI PVCs. CONCLUSIONS Variable CI PVCs affect critical populations of intrinsic cardiac nervous system neurons and alter cardiac repolarization. These changes may be critical for arrhythmogenesis and remodeling, leading to cardiomyopathy.
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Affiliation(s)
- David Hamon
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Pradeep S Rajendran
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Ray W Chui
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Olujimi A Ajijola
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Tadanobu Irie
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Ramin Talebi
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Siamak Salavatian
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Marmar Vaseghi
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Jason S Bradfield
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - J Andrew Armour
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Jeffrey L Ardell
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles
| | - Kalyanam Shivkumar
- From the Cardiac Arrhythmia Center (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.S.B., J.A.A., J.L.A., K.S.), Neurocardiology Research Center of Excellence (D.H., P.S.R., R.W.C., O.A.A., T.I., R.T., S.S., M.V., J.A.A., J.L.A., K.S.), and Molecular, Cellular & Integrative Physiology Program (P.S.R., R.W.C., M.V., J.L.A., K.S.), David Geffen School of Medicine, University of California-Los Angeles.
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22
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Jungen C, Scherschel K, Eickholt C, Kuklik P, Klatt N, Bork N, Salzbrunn T, Alken F, Angendohr S, Klene C, Mester J, Klöcker N, Veldkamp MW, Schumacher U, Willems S, Nikolaev VO, Meyer C. Disruption of cardiac cholinergic neurons enhances susceptibility to ventricular arrhythmias. Nat Commun 2017; 8:14155. [PMID: 28128201 PMCID: PMC5290156 DOI: 10.1038/ncomms14155] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 11/28/2016] [Indexed: 12/19/2022] Open
Abstract
The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular electrophysiology is unclear. Here we show that cardiac cholinergic neurons modulate ventricular electrophysiology. Mechanical disruption or pharmacological blockade of parasympathetic innervation shortens ventricular refractory periods, increases the incidence of ventricular arrhythmia and decreases ventricular cAMP levels in murine hearts. Immunohistochemistry confirmed ventricular cholinergic innervation, revealing parasympathetic fibres running from the atria to the ventricles parallel to sympathetic fibres. In humans, catheter ablation of atrial fibrillation, which is accompanied by accidental parasympathetic and concomitant sympathetic denervation, raises the burden of premature ventricular complexes. In summary, our results demonstrate an influence of cardiac cholinergic neurons on the regulation of ventricular function and arrhythmogenesis. Catheter ablation is a common therapy for atrial fibrillation but disrupts cardiac cholinergic neurons. Here the authors report that cholinergic neurons innervate heart ventricles and show that their ablation leads to increased susceptibility to ventricular arrhythmias in mouse models and in patients.
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Affiliation(s)
- Christiane Jungen
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany
| | - Katharina Scherschel
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany
| | - Christian Eickholt
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Pawel Kuklik
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Niklas Klatt
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany
| | - Nadja Bork
- DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany.,Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Tim Salzbrunn
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Fares Alken
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Stephan Angendohr
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Christiane Klene
- Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Janos Mester
- Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Nikolaj Klöcker
- Institute of Neural and Sensory Physiology, Medical Faculty, University of Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Marieke W Veldkamp
- Academic Medical Center, University of Amsterdam, Department of Clinical and Experimental Cardiology, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Udo Schumacher
- Institute of Anatomy and Experimental Morphology, University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Stephan Willems
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany
| | - Viacheslav O Nikolaev
- DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany.,Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Christian Meyer
- Department of Cardiology-Electrophysiology, cardiac Neuro- and Electrophysiology Research Group (cNEP), University Heart Center, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.,DZHK (German Center for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, 13347 Berlin, Germany
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23
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Buckley U, Rajendran PS, Shivkumar K. Ganglionated plexus ablation for atrial fibrillation: Just because we can, does that mean we should? Heart Rhythm 2017; 14:133-134. [PMID: 28007095 PMCID: PMC5378161 DOI: 10.1016/j.hrthm.2016.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Indexed: 11/23/2022]
Affiliation(s)
- Una Buckley
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, California
| | - Pradeep S Rajendran
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, California,; Molecular, Cellular and Integrative Physiology Program, David Geffen School of Medicine, UCLA, Los Angeles, California
| | - Kalyanam Shivkumar
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, California,; Molecular, Cellular and Integrative Physiology Program, David Geffen School of Medicine, UCLA, Los Angeles, California.
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24
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Smith FM, Vermeulen M, Cardinal R. Long-term spinal cord stimulation modifies canine intrinsic cardiac neuronal properties and ganglionic transmission during high-frequency repetitive activation. Physiol Rep 2016; 4:4/13/e12855. [PMID: 27401459 PMCID: PMC4945838 DOI: 10.14814/phy2.12855] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 06/16/2016] [Indexed: 12/28/2022] Open
Abstract
Long‐term spinal cord stimulation (SCS) applied to cranial thoracic SC segments exerts antiarrhythmic and cardioprotective actions in the canine heart in situ. We hypothesized that remodeling of intrinsic cardiac neuronal and synaptic properties occur in canines subjected to long‐term SCS, specifically that synaptic efficacy may be preferentially facilitated at high presynaptic nerve stimulation frequencies. Animals subjected to continuous SCS for 5–8 weeks (long‐term SCS: n = 17) or for 1 h (acute SCS: n = 4) were compared with corresponding control animals (long‐term: n = 15, acute: n = 4). At termination, animals were anesthetized, the heart was excised and neurones from the right atrial ganglionated plexus were identified and studied in vitro using standard intracellular microelectrode technique. Main findings were as follows: (1) a significant reduction in whole cell membrane input resistance and acceleration of the course of AHP decay identified among phasic neurones from long‐term SCS compared with controls, (2) significantly more robust synaptic transmission to rundown in long‐term SCS during high‐frequency (10–40 Hz) presynaptic nerve stimulation while recording from either phasic or accommodating postsynaptic neurones; this was associated with significantly greater posttrain excitatory postsynaptic potential (EPSP) numbers in long‐term SCS than control, and (3) synaptic efficacy was significantly decreased by atropine in both groups. Such changes did not occur in acute SCS. In conclusion, modification of intrinsic cardiac neuronal properties and facilitation of synaptic transmission at high stimulation frequency in long‐term SCS could improve physiologically modulated vagal inputs to the heart.
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Affiliation(s)
- Frank M Smith
- Department of Medical Neuroscience, Faculty of Medicine Dalhousie University, Halifax, Nova Scotia, Canada
| | - Michel Vermeulen
- Department of Pharmacology, Faculté de médecine Université de Montréal and Centre de recherche Hôpital du Sacré-Cœur de Montréal, Montréal, Quebec, Canada
| | - René Cardinal
- Department of Pharmacology, Faculté de médecine Université de Montréal and Centre de recherche Hôpital du Sacré-Cœur de Montréal, Montréal, Quebec, Canada
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25
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Abstract
Cardiac control is mediated via a series of reflex control networks involving somata in the (i) intrinsic cardiac ganglia (heart), (ii) intrathoracic extracardiac ganglia (stellate, middle cervical), (iii) superior cervical ganglia, (iv) spinal cord, (v) brainstem, and (vi) higher centers. Each of these processing centers contains afferent, efferent, and local circuit neurons, which interact locally and in an interdependent fashion with the other levels to coordinate regional cardiac electrical and mechanical indices on a beat-to-beat basis. This control system is optimized to respond to normal physiological stressors (standing, exercise, and temperature); however, it can be catastrophically disrupted by pathological events such as myocardial ischemia. In fact, it is now recognized that autonomic dysregulation is central to the evolution of heart failure and arrhythmias. Autonomic regulation therapy is an emerging modality in the management of acute and chronic cardiac pathologies. Neuromodulation-based approaches that target select nexus points of this hierarchy for cardiac control offer unique opportunities to positively affect therapeutic outcomes via improved efficacy of cardiovascular reflex control. As such, understanding the anatomical and physiological basis for such control is necessary to implement effectively novel neuromodulation therapies. © 2016 American Physiological Society. Compr Physiol 6:1635-1653, 2016.
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Affiliation(s)
- Jeffrey L Ardell
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
| | - John Andrew Armour
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
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26
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Salavatian S, Beaumont E, Longpré JP, Armour JA, Vinet A, Jacquemet V, Shivkumar K, Ardell JL. Vagal stimulation targets select populations of intrinsic cardiac neurons to control neurally induced atrial fibrillation. Am J Physiol Heart Circ Physiol 2016; 311:H1311-H1320. [PMID: 27591222 DOI: 10.1152/ajpheart.00443.2016] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/30/2016] [Indexed: 12/30/2022]
Abstract
Mediastinal nerve stimulation (MNS) reproducibly evokes atrial fibrillation (AF) by excessive and heterogeneous activation of intrinsic cardiac (IC) neurons. This study evaluated whether preemptive vagus nerve stimulation (VNS) impacts MNS-induced evoked changes in IC neural network activity to thereby alter susceptibility to AF. IC neuronal activity in the right atrial ganglionated plexus was directly recorded in anesthetized canines (n = 8) using a linear microelectrode array concomitant with right atrial electrical activity in response to: 1) epicardial touch or great vessel occlusion vs. 2) stellate or vagal stimulation. From these stressors, post hoc analysis (based on the Skellam distribution) defined IC neurons so recorded as afferent, efferent, or convergent (afferent and efferent inputs) local circuit neurons (LCN). The capacity of right-sided MNS to modify IC activity in the induction of AF was determined before and after preemptive right (RCV)- vs. left (LCV)-sided VNS (15 Hz, 500 μs; 1.2× bradycardia threshold). Neuronal (n = 89) activity at baseline (0.11 ± 0.29 Hz) increased during MNS-induced AF (0.51 ± 1.30 Hz; P < 0.001). Convergent LCNs were preferentially activated by MNS. Preemptive RCV reduced MNS-induced changes in LCN activity (by 70%) while mitigating MNS-induced AF (by 75%). Preemptive LCV reduced LCN activity by 60% while mitigating AF potential by 40%. IC neuronal synchrony increased during neurally induced AF, a local neural network response mitigated by preemptive VNS. These antiarrhythmic effects persisted post-VNS for, on average, 26 min. In conclusion, VNS preferentially targets convergent LCNs and their interactive coherence to mitigate the potential for neurally induced AF. The antiarrhythmic properties imposed by VNS exhibit memory.
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Affiliation(s)
- Siamak Salavatian
- Faculty of Medicine, Department of Physiology, Université de Montréal, Quebec, Canada.,Centre de Recherche, Hôpital du Sacré-Coeur, Montréal, Quebec, Canada.,Neurocardiology Research Center of Excellence, University of California Los Angeles, Los Angeles, California; and
| | - Eric Beaumont
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Jean-Philippe Longpré
- Faculty of Medicine, Department of Physiology, Université de Montréal, Quebec, Canada.,Centre de Recherche, Hôpital du Sacré-Coeur, Montréal, Quebec, Canada
| | - J Andrew Armour
- Neurocardiology Research Center of Excellence, University of California Los Angeles, Los Angeles, California; and.,Cardiac Arrhythmia Center, University of California Los Angeles, Los Angeles, California
| | - Alain Vinet
- Faculty of Medicine, Department of Physiology, Université de Montréal, Quebec, Canada.,Centre de Recherche, Hôpital du Sacré-Coeur, Montréal, Quebec, Canada
| | - Vincent Jacquemet
- Faculty of Medicine, Department of Physiology, Université de Montréal, Quebec, Canada.,Centre de Recherche, Hôpital du Sacré-Coeur, Montréal, Quebec, Canada
| | - Kalyanam Shivkumar
- Neurocardiology Research Center of Excellence, University of California Los Angeles, Los Angeles, California; and.,Cardiac Arrhythmia Center, University of California Los Angeles, Los Angeles, California
| | - Jeffrey L Ardell
- Neurocardiology Research Center of Excellence, University of California Los Angeles, Los Angeles, California; and .,Cardiac Arrhythmia Center, University of California Los Angeles, Los Angeles, California
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27
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Wake E, Brack K. Characterization of the intrinsic cardiac nervous system. Auton Neurosci 2016; 199:3-16. [DOI: 10.1016/j.autneu.2016.08.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/29/2016] [Accepted: 08/03/2016] [Indexed: 11/29/2022]
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28
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Shivkumar K, Ajijola OA, Anand I, Armour JA, Chen PS, Esler M, De Ferrari GM, Fishbein MC, Goldberger JJ, Harper RM, Joyner MJ, Khalsa SS, Kumar R, Lane R, Mahajan A, Po S, Schwartz PJ, Somers VK, Valderrabano M, Vaseghi M, Zipes DP. Clinical neurocardiology defining the value of neuroscience-based cardiovascular therapeutics. J Physiol 2016; 594:3911-54. [PMID: 27114333 PMCID: PMC4945719 DOI: 10.1113/jp271870] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 04/08/2016] [Indexed: 12/13/2022] Open
Abstract
The autonomic nervous system regulates all aspects of normal cardiac function, and is recognized to play a critical role in the pathophysiology of many cardiovascular diseases. As such, the value of neuroscience-based cardiovascular therapeutics is increasingly evident. This White Paper reviews the current state of understanding of human cardiac neuroanatomy, neurophysiology, pathophysiology in specific disease conditions, autonomic testing, risk stratification, and neuromodulatory strategies to mitigate the progression of cardiovascular diseases.
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Affiliation(s)
- Kalyanam Shivkumar
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, CA, USA
| | - Olujimi A Ajijola
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, CA, USA
| | - Inder Anand
- Department of Cardiology, University of Minnesota Medical School, Minneapolis, MN, USA
| | - J Andrew Armour
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, CA, USA
| | - Peng-Sheng Chen
- Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Murray Esler
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | | | - Michael C Fishbein
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Jeffrey J Goldberger
- Division of Cardiology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Ronald M Harper
- Department of Neurobiology and the Brain Research Institute, University of California, Los Angeles, CA, USA
| | - Michael J Joyner
- Division of Cardiovascular Diseases, Mayo Clinic and Mayo Foundation, Rochester, MN, USA
| | | | - Rajesh Kumar
- Departments of Anesthesiology and Radiological Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Richard Lane
- Department of Psychiatry, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Aman Mahajan
- Department of Anesthesia, UCLA, Los Angeles, CA, USA
| | - Sunny Po
- Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- University of Tulsa Oxley College of Health Sciences, Tulsa, OK, USA
| | - Peter J Schwartz
- Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Instituto Auxologico Italiano, c/o Centro Diagnostico e di Ricerrca San Carlo, Milan, Italy
| | - Virend K Somers
- Division of Cardiovascular Diseases, Mayo Clinic and Mayo Foundation, Rochester, MN, USA
| | - Miguel Valderrabano
- Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, Houston Methodist Hospital, Houston, TX, USA
| | - Marmar Vaseghi
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center of Excellence, Los Angeles, CA, USA
| | - Douglas P Zipes
- Indiana University School of Medicine, Indianapolis, IN, USA
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29
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Ardell JL, Andresen MC, Armour JA, Billman GE, Chen PS, Foreman RD, Herring N, O'Leary DS, Sabbah HN, Schultz HD, Sunagawa K, Zucker IH. Translational neurocardiology: preclinical models and cardioneural integrative aspects. J Physiol 2016; 594:3877-909. [PMID: 27098459 DOI: 10.1113/jp271869] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/14/2016] [Indexed: 12/15/2022] Open
Abstract
Neuronal elements distributed throughout the cardiac nervous system, from the level of the insular cortex to the intrinsic cardiac nervous system, are in constant communication with one another to ensure that cardiac output matches the dynamic process of regional blood flow demand. Neural elements in their various 'levels' become differentially recruited in the transduction of sensory inputs arising from the heart, major vessels, other visceral organs and somatic structures to optimize neuronal coordination of regional cardiac function. This White Paper will review the relevant aspects of the structural and functional organization for autonomic control of the heart in normal conditions, how these systems remodel/adapt during cardiac disease, and finally how such knowledge can be leveraged in the evolving realm of autonomic regulation therapy for cardiac therapeutics.
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Affiliation(s)
- J L Ardell
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| | - M C Andresen
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - J A Armour
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| | - G E Billman
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA
| | - P-S Chen
- The Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - R D Foreman
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - N Herring
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - D S O'Leary
- Department of Physiology, Wayne State University, Detroit, MI, USA
| | - H N Sabbah
- Department of Medicine, Henry Ford Hospital, Detroit, MI, USA
| | - H D Schultz
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - K Sunagawa
- Department of Cardiovascular Medicine, Kyushu University, Fukuoka, Japan
| | - I H Zucker
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
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Beaumont E, Wright GL, Southerland EM, Li Y, Chui R, KenKnight BH, Armour JA, Ardell JL. Vagus nerve stimulation mitigates intrinsic cardiac neuronal remodeling and cardiac hypertrophy induced by chronic pressure overload in guinea pig. Am J Physiol Heart Circ Physiol 2016; 310:H1349-59. [PMID: 26993230 DOI: 10.1152/ajpheart.00939.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 03/17/2016] [Indexed: 02/06/2023]
Abstract
Our objective was to determine whether chronic vagus nerve stimulation (VNS) mitigates pressure overload (PO)-induced remodeling of the cardioneural interface. Guinea pigs (n = 48) were randomized to right or left cervical vagus (RCV or LCV) implant. After 2 wk, chronic left ventricular PO was induced by partial (15-20%) aortic constriction. Of the 31 animals surviving PO induction, 10 were randomized to RCV VNS, 9 to LCV VNS, and 12 to sham VNS. VNS was delivered at 20 Hz and 1.14 ± 0.03 mA at a 22% duty cycle. VNS commenced 10 days after PO induction and was maintained for 40 days. Time-matched controls (n = 9) were evaluated concurrently. Echocardiograms were obtained before and 50 days after PO. At termination, intracellular current-clamp recordings of intrinsic cardiac (IC) neurons were studied in vitro to determine effects of therapy on soma characteristics. Ventricular cardiomyocyte sizes were assessed with histology along with immunoblot analysis of selected proteins in myocardial tissue extracts. In sham-treated animals, PO increased cardiac output (34%, P < 0.004), as well as systolic (114%, P < 0.04) and diastolic (49%, P < 0.002) left ventricular volumes, a hemodynamic response prevented by VNS. PO-induced enhancements of IC synaptic efficacy and muscarinic sensitivity of IC neurons were mitigated by chronic VNS. Increased myocyte size, which doubled in PO (P < 0.05), was mitigated by RCV. PO hypertrophic myocardium displayed decreased glycogen synthase (GS) protein levels and accumulation of the phosphorylated (inactive) form of GS. These PO-induced changes in GS were moderated by left VNS. Chronic VNS targets IC neurons accompanying PO to obtund associated adverse cardiomyocyte remodeling.
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Affiliation(s)
- Eric Beaumont
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | - Gary L Wright
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | - Elizabeth M Southerland
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | - Ying Li
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | - Ray Chui
- Molecular, Cellular, and Integrative Physiology Program, University of California, Los Angeles, California
| | | | - J Andrew Armour
- UCLA Neurocardiology Research Center of Excellence and UCLA Cardiac Arrhythmia Center, Los Angeles, California
| | - Jeffrey L Ardell
- Molecular, Cellular, and Integrative Physiology Program, University of California, Los Angeles, California; UCLA Neurocardiology Research Center of Excellence and UCLA Cardiac Arrhythmia Center, Los Angeles, California
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Rajendran PS, Nakamura K, Ajijola OA, Vaseghi M, Armour JA, Ardell JL, Shivkumar K. Myocardial infarction induces structural and functional remodelling of the intrinsic cardiac nervous system. J Physiol 2015; 594:321-41. [PMID: 26572244 DOI: 10.1113/jp271165] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 11/12/2015] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Intrinsic cardiac (IC) neurons undergo differential morphological and phenotypic remodelling that reflects the site of myocardial infarction (MI). Afferent neural signals from the infarcted region to IC neurons are attenuated, while those from border and remote regions are preserved post-MI, giving rise to a 'neural sensory border zone'. Convergent IC local circuit (processing) neurons have enhanced transduction capacity following MI. Functional network connectivity within the intrinsic cardiac nervous system is reduced post-MI. MI reduces the response and alters the characteristics of IC neurons to ventricular pacing. ABSTRACT Autonomic dysregulation following myocardial infarction (MI) is an important pathogenic event. The intrinsic cardiac nervous system (ICNS) is a neural network located on the heart that is critically involved in autonomic regulation. The aims of this study were to characterize structural and functional remodelling of the ICNS post-MI in a porcine model (control (n = 16) vs. healed anteroapical MI (n = 16)). In vivo microelectrode recordings of basal activity, as well as responses to afferent and efferent stimuli, were recorded from intrinsic cardiac neurons. From control 118 neurons and from MI animals 102 neurons were functionally classified as afferent, efferent, or convergent (receiving both afferent and efferent inputs). In control and MI, convergent neurons represented the largest subpopulation (47% and 48%, respectively) and had enhanced transduction capacity following MI. Efferent inputs to neurons were maintained post-MI. Afferent inputs were attenuated from the infarcted region (19% in control vs. 7% in MI; P = 0.03), creating a 'neural sensory border zone', or heterogeneity in afferent information. MI reduced transduction of changes in preload (54% in control vs. 41% in MI; P = 0.05). The overall functional network connectivity, or the ability of neurons to respond to independent pairs of stimuli, within the ICNS was reduced following MI. The neuronal response was differentially decreased to ventricular vs. atrial pacing post-MI (63% in control vs. 44% in MI to ventricular pacing; P < 0.01). MI induced morphological and phenotypic changes within the ICNS. The alteration of afferent neural signals, and remodelling of convergent neurons, represents a 'neural signature' of ischaemic heart disease.
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Affiliation(s)
- Pradeep S Rajendran
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.,Molecular, Cellular & Integrative Physiology Program, UCLA, Los Angeles, CA, USA
| | - Keijiro Nakamura
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Olujimi A Ajijola
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Marmar Vaseghi
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.,Molecular, Cellular & Integrative Physiology Program, UCLA, Los Angeles, CA, USA
| | - J Andrew Armour
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Jeffrey L Ardell
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.,Molecular, Cellular & Integrative Physiology Program, UCLA, Los Angeles, CA, USA
| | - Kalyanam Shivkumar
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,Neurocardiology Research Center of Excellence, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.,Molecular, Cellular & Integrative Physiology Program, UCLA, Los Angeles, CA, USA
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Ardell JL, Rajendran PS, Nier HA, KenKnight BH, Armour JA. Central-peripheral neural network interactions evoked by vagus nerve stimulation: functional consequences on control of cardiac function. Am J Physiol Heart Circ Physiol 2015; 309:H1740-52. [PMID: 26371171 DOI: 10.1152/ajpheart.00557.2015] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/10/2015] [Indexed: 12/19/2022]
Abstract
Using vagus nerve stimulation (VNS), we sought to determine the contribution of vagal afferents to efferent control of cardiac function. In anesthetized dogs, the right and left cervical vagosympathetic trunks were stimulated in the intact state, following ipsilateral or contralateral vagus nerve transection (VNTx), and then following bilateral VNTx. Stimulations were performed at currents from 0.25 to 4.0 mA, frequencies from 2 to 30 Hz, and a 500-μs pulse width. Right or left VNS evoked significantly greater current- and frequency-dependent suppression of chronotropic, inotropic, and lusitropic function subsequent to sequential VNTx. Bradycardia threshold was defined as the current first required for a 5% decrease in heart rate. The threshold for the right vs. left vagus-induced bradycardia in the intact state (2.91 ± 0.18 and 3.47 ± 0.20 mA, respectively) decreased significantly with right VNTx (1.69 ± 0.17 mA for right and 3.04 ± 0.27 mA for left) and decreased further following bilateral VNTx (1.29 ± 0.16 mA for right and 1.74 ± 0.19 mA for left). Similar effects were observed following left VNTx. The thresholds for afferent-mediated effects on cardiac parameters were 0.62 ± 0.04 and 0.65 ± 0.06 mA with right and left VNS, respectively, and were reflected primarily as augmentation. Afferent-mediated tachycardias were maintained following β-blockade but were eliminated by VNTx. The increased effectiveness and decrease in bradycardia threshold with sequential VNTx suggest that 1) vagal afferents inhibit centrally mediated parasympathetic efferent outflow and 2) the ipsilateral and contralateral vagi exert a substantial buffering capacity. The intact threshold reflects the interaction between multiple levels of the cardiac neural hierarchy.
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Affiliation(s)
- Jeffrey L Ardell
- Neurocardiology Research Center of Excellence, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California; Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California; Molecular, Cellular, and Integrative Physiology Program, University of California-Los Angeles, Los Angeles, California;
| | - Pradeep S Rajendran
- Neurocardiology Research Center of Excellence, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California; Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California; Molecular, Cellular, and Integrative Physiology Program, University of California-Los Angeles, Los Angeles, California
| | - Heath A Nier
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee; and
| | | | - J Andrew Armour
- Neurocardiology Research Center of Excellence, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California; Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California
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Moss E, Cardinal R, Yin Y, Pagé P. Biatrial neuroablation attenuates atrial remodeling and vulnerability to atrial fibrillation in canine chronic rapid atrial pacing. Auton Neurosci 2015; 189:43-9. [PMID: 25746009 DOI: 10.1016/j.autneu.2015.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 12/24/2014] [Accepted: 02/17/2015] [Indexed: 11/26/2022]
Abstract
AIMS We investigated the proposition that an intact cardiac nervous system may contribute to electrophysiological remodeling and increased vulnerability to atrial fibrillation (AF) following chronic rapid atrial pacing (RAP). METHODS AND RESULTS Baseline study was conducted prior to ablating right and left ganglionated plexuses (RAGP, LAGP) in 11 anesthetized canines (Neuroablation group) and in 11 canines without neuroablation (Intact GP). After being subjected to RAP (400 beats/min) for 6 weeks, animals were reanesthetized for terminal study. The ERP shortening typical of chronic RAP was significantly more pronounced in the Intact GP (baseline: 112 ± 12 to terminal: 80 ± 11 ms) than in the Neuroablation group (113 ± 18 to 102 ± 21 ms, p < .001), and AF inducibility (extrastimulus protocol) showed significantly greater increment in the Intact GP (baseline: 23 ± 19% to terminal: 60 ± 17% of trials) than in the Neuroablation group (18 ± 15% to 27 ± 17%, p = 0.029). Negative chronotropic responses to right vagus nerve stimulation were markedly reduced immediately after the neuroablation procedure but had recovered at terminal study. Vagally-evoked repolarization changes (from 191 unipolar electrograms) occurred in a majority of Intact GP animals in the superior, middle and inferior RA free wall, and in the LA appendage. In the Neuroablation group, repolarization changes were restricted to the superior RA free wall but none occurred in the inferior RA and only infrequently in the LA appendage, yielding significantly smaller affected areas in Neuroablation than in Intact GP animals. CONCLUSION Persistent functional denervation in LA and RA regions other than RA pacemaker areas may contribute to prevent the development of a tachycardia-dependent AF substrate.
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Affiliation(s)
- Emmanuel Moss
- Centre de recherche, Hôpital du Sacré-Cœur de Montréal, Montréal, Canada; Department of Surgery, Université de Montréal, Montreal, Canada
| | - René Cardinal
- Centre de recherche, Hôpital du Sacré-Cœur de Montréal, Montréal, Canada; Department of Pharmacology, Université de Montréal, Montreal, Canada
| | - Yalin Yin
- Centre de recherche, Hôpital du Sacré-Cœur de Montréal, Montréal, Canada
| | - Pierre Pagé
- Centre de recherche, Hôpital du Sacré-Cœur de Montréal, Montréal, Canada; Department of Surgery, Université de Montréal, Montreal, Canada.
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Autonomic Regulation Therapy via Left or Right Cervical Vagus Nerve Stimulation in Patients With Chronic Heart Failure: Results of the ANTHEM-HF Trial. J Card Fail 2014; 20:808-16. [DOI: 10.1016/j.cardfail.2014.08.009] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 08/18/2014] [Accepted: 08/18/2014] [Indexed: 01/12/2023]
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Brack KE. The heart's 'little brain' controlling cardiac function in the rabbit. Exp Physiol 2014; 100:348-53. [PMID: 25833107 PMCID: PMC4409095 DOI: 10.1113/expphysiol.2014.080168] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 09/19/2014] [Indexed: 12/31/2022]
Abstract
NEW FINDINGS What is the topic of this review? The topic of the review is the intrinsic cardiac nervous system in the rabbit. What advances does it highlight? The anatomy of rabbit intrinsic ganglia is similar to that of other species, including humans. Immunohistochemistry confirms the presence of cholinergic and adrenergic neurones, with a striking arrangement of neuronal nitric oxide synthase-positive cell bodies. Activation of atrial ganglia produces effects on local and remote regions. Heart disease is a primary cause of mortality in the developed world, and it is well recognized that neural mechanisms play an important role in many cardiac pathologies. The role of extrinsic autonomic nerves has traditionally attracted the most attention. However, there is a rich intrinsic innervation of the heart, including numerous cardiac ganglia (ganglionic plexuses), that has the potential to affect cardiac function independently as well as to influence the actions of the extrinsic nerves. To investigate this, an isolated, perfused, innervated rabbit Langendorff heart preparation was considered the best option. Although ganglionic plexuses have been well described for several species, there was no full description of the anatomy and histochemistry of rabbit hearts. To this end, rabbit intrinsic ganglia were located using acetylcholinesterase histology (n = 33 hearts). This revealed six generalized ganglionic regions, defined as a left neuronal complex above the left pulmonary vein, a right neuronal complex around the base of right cranial vein, three scattered in the dorsal right atrium and a region containing numerous ventricular ganglia located on the conus arteriosus. Using immunohistochemistry, neurons were found to contain choline acetyltransferase or tyrosine hydroxylase and/or neuronal nitric oxide synthase in differing amounts (choline acetyltransferase > tyrosine hydroxylase > neuronal nitric oxide synthase). The function of rabbit intrinsic ganglia was investigated using a bolus application of nicotine or electrical stimulation at each of the above sites whilst measuring heart rate and atrioventricular conduction. Nicotine applied to different ganglionic plexuses caused a bradycardia, a tachycardia or a mixture of the two, with the right atrial plexus producing the largest chronotropic responses. Electrical stimulation at these sites induced only a bradycardia. Atrioventricular conduction was modestly changed by nicotine, the main response being a prolongation. Electrical stimulation produced significant prolongation of atrioventricular conduction, particularly when the right neuronal complex was stimulated. These studies show that the intrinsic plexuses of the heart are important and could be crucial for understanding impairments of cardiac function. Additionally, they provide a strong basis from which to progress using the isolated, innervated rabbit heart preparation.
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Affiliation(s)
- Kieran E Brack
- Department of Cardiovascular Sciences, Cardiology Group, Glenfield Hospital, University of Leicester, UK; Leicester NIHR Biomedical Research Unit in Cardiovascular Disease, Glenfield Hospital, Leicester, UK
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Rajendran PS, Buch E, Shivkumar K. Marshaling the autonomic nervous system for treatment of atrial fibrillation. J Am Coll Cardiol 2014; 63:1902-3. [PMID: 24561143 DOI: 10.1016/j.jacc.2014.01.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 01/20/2014] [Indexed: 01/20/2023]
Affiliation(s)
- Pradeep S Rajendran
- UCLA Cardiac Arrhythmia Center, UCLA, Los Angeles, California; David Geffen School of Medicine, UCLA, Los Angeles, California; Molecular, Cellular and Integrative Physiology Program, UCLA, Los Angeles, California; Neurocardiology Program, Center for Neurobiology of Stress, UCLA, Los Angeles, California
| | - Eric Buch
- UCLA Cardiac Arrhythmia Center, UCLA, Los Angeles, California; David Geffen School of Medicine, UCLA, Los Angeles, California
| | - Kalyanam Shivkumar
- UCLA Cardiac Arrhythmia Center, UCLA, Los Angeles, California; David Geffen School of Medicine, UCLA, Los Angeles, California; Molecular, Cellular and Integrative Physiology Program, UCLA, Los Angeles, California; Neurocardiology Program, Center for Neurobiology of Stress, UCLA, Los Angeles, California.
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Petraitiene V, Pauza DH, Benetis R. Distribution of adrenergic and cholinergic nerve fibres within intrinsic nerves at the level of the human heart hilum. Eur J Cardiothorac Surg 2013; 45:1097-105. [PMID: 24335471 DOI: 10.1093/ejcts/ezt575] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES The disbalance between adrenergic (sympathetic) and cholinergic (parasympathetic) cardiac inputs facilitates cardiac arrhythmias, including the lethal ones. In spite of the fact that the morphological pattern of the epicardiac ganglionated subplexuses (ENsubP) has been previously described in detail, the distribution of functionally distinct axons in human intrinsic nerves was not investigated thus far. Therefore, the aim of the present study was to quantitatively evaluate the distribution of tyrosine hydroxylase (TH)- and choline acetyltransferase (ChAT)-positive axons within intrinsic nerves at the level of the human heart hilum (HH), since they are of pivotal importance for determining proper treatment options for different arrhythmias. METHODS Tissue samples containing the intrinsic nerves from seven epicardiac subplexuses were obtained from nine human hearts without cardiac pathology and processed for immunofluorescent detection of TH and ChAT. The nerve area was measured and the numbers of axons were counted using microphotographs of nerve profiles. The densities of fibres were extrapolated and compared between subplexuses. RESULTS ChAT-immunoreactive (IR) fibres were evidently predominant (>56%) in nerves of dorsal (DRA) and ventral right atrial (VRA) ENsubP. Within both left (LC) and right coronary ENsubP, the most abundant (70.9 and 83.0%, respectively) were TH-IR axons. Despite subplexal dependence, ChAT-IR fibres prevailed in comparatively thinner nerves, whereas TH-IR fibres in thicker ones. Morphometry showed that at the level of HH: (i) LC subplexal nerves were found to be the thickest (25 737 ± 4131 μm(2)) ones, whereas the thinnest (2604 ± 213 μm(2)) nerves concentrated in DRA ENsubP; (ii) the density of ChAT-IR axons was highest (6.8 ± 0.6/100 μm(2)) in the ventral left atrial nerves and lowest (3.2 ± 0.1/100 μm(2)) in left dorsal ENsubP and (iii) the density of TH-IR fibres was highest (15.9 ± 2.1/100 μm(2)) in LC subplexal nerves and lowest (4.4 ± 0.3/100 μm(2)) in VRA nerves. CONCLUSIONS (i) The principal intrinsic adrenergic neural pathways in the human heart proceed via both coronary ENsubP that supply cardiac ventricles and (ii) the majority of cholinergic nerve fibres access the human heart through DRA and VRA ENsubP and extend towards the right atrium, including the region of the sinuatrial node.
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Affiliation(s)
- Viktorija Petraitiene
- Institute of Anatomy, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Dainius H Pauza
- Institute of Anatomy, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Rimantas Benetis
- Institute of Cardiology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
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Abstract
The role of cardiac nerves on development of myocardial tissue injury after acute coronary occlusion remains controversial. We investigated whether acute cardiac decentralization (surgical) modulates coronary flow reserve and myocardial protection in preconditioned dogs subject to ischemia-reperfusion. Experiments were conducted on four groups of anesthetised, open-chest dogs (n = 32): 1- controls (CTR, intact cardiac nerves), 2- ischemic preconditioning (PC; 4 cycles of 5-min IR), 3- cardiac decentralization (CD) and 4- CD+PC; all dogs underwent 60-min coronary occlusion and 180-min reperfusion. Coronary blood flow and reactive hyperemic responses were assessed using a blood volume flow probe. Infarct size (tetrazolium staining) was related to anatomic area at risk and coronary collateral blood flow (microspheres) in the anatomic area at risk. Post-ischemic reactive hyperemia and repayment-to-debt ratio responses were significantly reduced for all experimental groups; however, arterial perfusion pressure was not affected. Infarct size was reduced in CD dogs (18.6±4.3; p = 0.001, data are mean±1SD) compared to 25.2±5.5% in CTR dogs and was less in PC dogs as expected (13.5±3.2 vs. 25.2±5.5%; p = 0.001); after acute CD, PC protection was conserved (11.6±3.4 vs. 18.6±4.3%; p = 0.02). In conclusion, our findings provide strong evidence that myocardial protection against ischemic injury can be preserved independent of extrinsic cardiac nerve inputs.
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Beaumont E, Salavatian S, Southerland EM, Vinet A, Jacquemet V, Armour JA, Ardell JL. Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function. J Physiol 2013; 591:4515-33. [PMID: 23818689 DOI: 10.1113/jphysiol.2013.259382] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The aims of the study were to determine how aggregates of intrinsic cardiac (IC) neurons transduce the cardiovascular milieu versus responding to changes in central neuronal drive and to determine IC network interactions subsequent to induced neural imbalances in the genesis of atrial fibrillation (AF). Activity from multiple IC neurons in the right atrial ganglionated plexus was recorded in eight anaesthetized canines using a 16-channel linear microelectrode array. Induced changes in IC neuronal activity were evaluated in response to: (1) focal cardiac mechanical distortion; (2) electrical activation of cervical vagi or stellate ganglia; (3) occlusion of the inferior vena cava or thoracic aorta; (4) transient ventricular ischaemia, and (5) neurally induced AF. Low level activity (ranging from 0 to 2.7 Hz) generated by 92 neurons was identified in basal states, activities that displayed functional interconnectivity. The majority (56%) of IC neurons so identified received indirect central inputs (vagus alone: 25%; stellate ganglion alone: 27%; both: 48%). Fifty per cent transduced the cardiac milieu responding to multimodal stressors applied to the great vessels or heart. Fifty per cent of IC neurons exhibited cardiac cycle periodicity, with activity occurring primarily in late diastole into isovolumetric contraction. Cardiac-related activity in IC neurons was primarily related to direct cardiac mechano-sensory inputs and indirect autonomic efferent inputs. In response to mediastinal nerve stimulation, most IC neurons became excessively activated; such network behaviour preceded and persisted throughout AF. It was concluded that stochastic interactions occur among IC local circuit neuronal populations in the control of regional cardiac function. Modulation of IC local circuit neuronal recruitment may represent a novel approach for the treatment of cardiac disease, including atrial arrhythmias.
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Affiliation(s)
- Eric Beaumont
- J. L. Ardell: Department of Biomedical Sciences, East Tennessee State University, Johnson City, TN 37614-0577, USA.
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Moss E, Cardinal R, Yin Y, Pagé P. Bilateral atrial ganglionated plexus involvement in atrial responses to left-sided plexus stimulation in canines. Cardiovasc Res 2013; 99:194-202. [DOI: 10.1093/cvr/cvt092] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jones DL, Tuomi JM, Chidiac P. Role of Cholinergic Innervation and RGS2 in Atrial Arrhythmia. Front Physiol 2012; 3:239. [PMID: 22754542 PMCID: PMC3386567 DOI: 10.3389/fphys.2012.00239] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 06/12/2012] [Indexed: 01/25/2023] Open
Abstract
The heart receives sympathetic and parasympathetic efferent innervation as well as the ability to process information internally via an intrinsic cardiac autonomic nervous system (ICANS). For over a century, the role of the parasympathetics via vagal acetylcholine release was related to controlling primarily heart rate. Although in the late 1800s shown to play a role in atrial arrhythmia, the myocardium took precedence from the mid-1950s until in the last decade a resurgence of interest in the autonomics along with signaling cascades, regulators, and ion channels. Originally ignored as being benign and thus untreated, recent emphasis has focused on atrial arrhythmia as atrial fibrillation (AF) is the most common arrhythmia seen by the general practitioner. It is now recognized to have significant mortality and morbidity due to resultant stroke and heart failure. With the aging population, there will be an unprecedented increased burden on health care resources. Although it has been known for more than half a century that cholinergic stimulation can initiate AF, the classical concept focused on the M2 receptor and its signaling cascade including RGS4, as these had been shown to have predominant effects on nodal function (heart rate and conduction block) as well as contractility. However, recent evidence suggests that the M3 receptor may also playa role in initiation and perpetuation of AF and thus RGS2, a putative regulator of the M3 receptor, may be a target for therapeutic intervention. Mice lacking RGS2 (RGS2−/−), were found to have significantly altered electrophysiological atrial responses and were more susceptible to electrically induced AF. Vagally induced or programmed stimulation-induced AF could be blocked by the selective M3R antagonist, darifenacin. These results suggest a potential surgical target (ICANS) and pharmacological targets (M3R, RGS2) for the management of AF.
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Affiliation(s)
- Douglas L Jones
- Department of Physiology and Pharmacology, The University of Western Ontario London, ON, Canada
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Cardinal R, Armour JA, Bouchard C, Vermeulen M, Vinet A, Nadeau R, Pagé P. Atrial Tachyarrhythmias and Repolarization Changes Induced by Discrete Activation of Dorsal Mediastinal Cardiac Nerves in Canines. Circ Arrhythm Electrophysiol 2010; 3:511-20. [DOI: 10.1161/circep.110.938050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Chronotropic “vagal responses” elicited by high-frequency stimulation have been used to identify atrial targets for ablative treatment of atrial tachyarrhythmias (AT), whereas an anatomic approach consisting of extensive ablation of the ganglionated plexus areas has been proposed as an alternative. Therefore, there is a need for precise delineation of juxtacardiac nerves involved in AT initiation and clarification of their regional influences throughout the atria in relation to AT sites of origin, beyond chronotropic effects related to sinus node modulation.
Methods and Results—
Unipolar electrograms were recorded from 191 biatrial epicardial sites in 13 anesthetized canines, with concomitant left atrial endocardial recording from 63 sites in 5 of 13 animals. When electric stimuli were delivered to dorsal mediastinal nerves during the atrial refractory period, atrial premature depolarizations initiating AT were elicited in all animals, most frequently without prior sinus cycle length modification. Among 63 episodes, the sites of origin of early AT beats were localized to (1) the posterolateral left atrial wall in the pulmonary vein region (33%), (2) superior left atrial loci along the Bachmann bundle (55%), and (3) the region of Bachmann bundle insertion into the superior right atrial wall (11%). Moreover, the AT sites of origin were spatially concordant with regional waveform changes during the repolarization phase of unipolar recordings. AT induction and repolarization changes were abolished after atropine administration.
Conclusions—
Activation of individual dorsal mediastinal nerves induces AT arising from distinct sites of origin which are spatially concordant with regional atrial repolarization changes.
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Affiliation(s)
- René Cardinal
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - J. Andrew Armour
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Caroline Bouchard
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Michel Vermeulen
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Alain Vinet
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Réginald Nadeau
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Pierre Pagé
- From the Centre de recherche (R.C., A.A., C.B., M.V., A.V., R.N., P.P.), Hôpital du Sacré-Cœur de Montréal, and the Departments of Pharmacology (R.C., A.A., C.B., M.V.) and Surgery (P.P.), Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
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Armour JA. Functional anatomy of intrathoracic neurons innervating the atria and ventricles. Heart Rhythm 2010; 7:994-6. [DOI: 10.1016/j.hrthm.2010.02.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Indexed: 10/19/2022]
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Volders PGA. Novel insights into the role of the sympathetic nervous system in cardiac arrhythmogenesis. Heart Rhythm 2010; 7:1900-6. [PMID: 20570754 DOI: 10.1016/j.hrthm.2010.06.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 06/01/2010] [Indexed: 11/15/2022]
Abstract
It has long been recognized that increased sympathetic nerve activity during physiologic stress (exercise, swimming, emotion, arousal, loud noise, etc.) has profound influences on the electrical and contractile functions of the heart. In the severely predisposed heart, these stressors may lead to ventricular tachyarrhythmias and sudden death. Still little is known about the temporal relationship between instantaneous autonomic nerve activity and arrhythmias. There is a large variety of autonomically-driven arrhythmias, from serious ventricular tachycardia in pathological conditions to single supraventricular and ventricular extrasystolic beats in the healthy heart. The latter are considered harmless if occurring at low frequency. In the atria, mounting data indicate the presence of a sophisticated network of ganglionated plexi with major influences on cardiac function. The ablation of multiple such ganglia can suppress pulmonary vein potentials and atrial fibrillation. At the cellular level, recent studies have focused on the spatiotemporal details of cyclic nucleotide signaling influencing ion channel function during neurohumoral stimulation. We have come to understand that sarcolemmal ion channels and other electrogenic transporters are macromolecular complexes that interact with structural elements (other than the phospholipid bilayer) to promote regionalization and targeting by regulatory proteins. Compartmentation of these regulatory proteins in subdomains of the myocyte is increasingly recognized and thought to segregate the functional (including electrogenic) responses induced by different neuromediators and hormones. In this article, contemporary issues are discussed regarding arrhythmias that are triggered by influences from the neurocardiac interface, covering the field from the molecular genetic to the intact integrated level. Actual questions are listed per topic, and viewpoints are expressed.
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Affiliation(s)
- Paul G A Volders
- Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University Medical Centre, Maastricht, The Netherlands.
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Hoover DB, Isaacs ER, Jacques F, Hoard JL, Pagé P, Armour JA. Localization of multiple neurotransmitters in surgically derived specimens of human atrial ganglia. Neuroscience 2009; 164:1170-9. [PMID: 19747529 DOI: 10.1016/j.neuroscience.2009.09.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 08/31/2009] [Accepted: 09/01/2009] [Indexed: 10/20/2022]
Abstract
Dysfunction of the intrinsic cardiac nervous system is implicated in the genesis of atrial and ventricular arrhythmias. While this system has been studied extensively in animal models, far less is known about the intrinsic cardiac nervous system of humans. This study was initiated to anatomically identify neurotransmitters associated with the right atrial ganglionated plexus (RAGP) of the human heart. Biopsies of epicardial fat containing a portion of the RAGP were collected from eight patients during cardiothoracic surgery and processed for immunofluorescent detection of specific neuronal markers. Colocalization of markers was evaluated by confocal microscopy. Most intrinsic cardiac neuronal somata displayed immunoreactivity for the cholinergic marker choline acetyltransferase and the nitrergic marker neuronal nitric oxide synthase. A subpopulation of intrinsic cardiac neurons also stained for noradrenergic markers. While most intrinsic cardiac neurons received cholinergic innervation evident as punctate immunostaining for the high affinity choline transporter, some lacked cholinergic inputs. Moreover, peptidergic, nitrergic, and noradrenergic nerves provided substantial innervation of intrinsic cardiac ganglia. These findings demonstrate that the human RAGP has a complex neurochemical anatomy, which includes the presence of a dual cholinergic/nitrergic phenotype for most of its neurons, the presence of noradrenergic markers in a subpopulation of neurons, and innervation by a host of neurochemically distinct nerves. The putative role of multiple neurotransmitters in controlling intrinsic cardiac neurons and mediating efferent signaling to the heart indicates the possibility of novel therapeutic targets for arrhythmia prevention.
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Affiliation(s)
- D B Hoover
- Department of Pharmacology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.
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Shan H, Zhang Y, Lu Y, Zhang Y, Pan Z, Cai B, Wang N, Li X, Feng T, Hong Y, Yang B. Downregulation of miR-133 and miR-590 contributes to nicotine-induced atrial remodelling in canines. Cardiovasc Res 2009; 83:465-72. [PMID: 19398468 DOI: 10.1093/cvr/cvp130] [Citation(s) in RCA: 263] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
AIMS The present study was designed to decipher molecular mechanisms underlying nicotine's promoting atrial fibrillation (AF) by inducing atrial structural remodelling. METHODS AND RESULTS The canine model of AF was successfully established by nicotine administration and rapid pacing. The atrial fibroblasts isolated from healthy dogs were treated with nicotine. The role of microRNAs (miRNAs) on the expression and regulation of transforming growth factor-beta1 (TGF-beta1), TGF-beta receptor type II (TGF-betaRII), and collagen production was evaluated in vivo and in vitro. Administration of nicotine for 30 days increased AF vulnerability by approximately eight- to 15-fold in dogs. Nicotine stimulated remarkable collagen production and atrial fibrosis both in vitro in cultured canine atrial fibroblasts and in vivo in atrial tissues. Nicotine produced significant upregulation of expression of TGF-beta1 and TGF-betaRII at the protein level, and a 60-70% decrease in the levels of miRNAs miR-133 and miR-590. This downregulation of miR-133 and miR-590 partly accounts for the upregulation of TGF-beta1 and TGF-betaRII, because our data established TGF-beta1 and TGF-betaRII as targets for miR-133 and miR-590 repression. Transfection of miR-133 or miR-590 into cultured atrial fibroblasts decreased TGF-beta1 and TGF-betaRII levels and collagen content. These effects were abolished by the antisense oligonucleotides against miR-133 or miR-590. The effects of nicotine were prevented by an alpha7 nicotinic acetylcholine receptor antagonist. CONCLUSION We conclude that the profibrotic response to nicotine in canine atrium is critically dependent upon downregulation of miR-133 and miR-590.
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Affiliation(s)
- Hongli Shan
- Department of Pharmacology, State-Province Key Laboratories of Biomedicine and Pharmaceutics, Harbin, Heilongjiang 150081, PR China
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