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Habecker BA, Bers DM, Birren SJ, Chang R, Herring N, Kay MW, Li D, Mendelowitz D, Mongillo M, Montgomery JM, Ripplinger CM, Tampakakis E, Winbo A, Zaglia T, Zeltner N, Paterson DJ. Molecular and cellular neurocardiology in heart disease. J Physiol 2024. [PMID: 38778747 DOI: 10.1113/jp284739] [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: 02/23/2024] [Accepted: 04/16/2024] [Indexed: 05/25/2024] Open
Abstract
This paper updates and builds on a previous White Paper in this journal that some of us contributed to concerning the molecular and cellular basis of cardiac neurobiology of heart disease. Here we focus on recent findings that underpin cardiac autonomic development, novel intracellular pathways and neuroplasticity. Throughout we highlight unanswered questions and areas of controversy. Whilst some neurochemical pathways are already demonstrating prognostic viability in patients with heart failure, we also discuss the opportunity to better understand sympathetic impairment by using patient specific stem cells that provides pathophysiological contextualization to study 'disease in a dish'. Novel imaging techniques and spatial transcriptomics are also facilitating a road map for target discovery of molecular pathways that may form a therapeutic opportunity to treat cardiac dysautonomia.
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Affiliation(s)
- Beth A Habecker
- Department of Chemical Physiology & Biochemistry, Department of Medicine Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| | - Donald M Bers
- Department of Pharmacology, University of California, Davis School of Medicine, Davis, CA, USA
| | - Susan J Birren
- Department of Biology, Volen Center for Complex Systems, Brandeis University, Waltham, MA, USA
| | - Rui Chang
- Department of Neuroscience, Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Neil Herring
- Burdon Sanderson Cardiac Science Centre and BHF Centre of Research Excellence, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Matthew W Kay
- Department of Biomedical Engineering, George Washington University, Washington, DC, USA
| | - Dan Li
- Burdon Sanderson Cardiac Science Centre and BHF Centre of Research Excellence, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - David Mendelowitz
- Department of Pharmacology and Physiology, George Washington University, Washington, DC, USA
| | - Marco Mongillo
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Johanna M Montgomery
- Department of Physiology and Manaaki Manawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Crystal M Ripplinger
- Department of Pharmacology, University of California, Davis School of Medicine, Davis, CA, USA
| | | | - Annika Winbo
- Department of Physiology and Manaaki Manawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Tania Zaglia
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Nadja Zeltner
- Departments of Biochemistry and Molecular Biology, Cell Biology, and Center for Molecular Medicine, University of Georgia, Athens, GA, USA
| | - David J Paterson
- Burdon Sanderson Cardiac Science Centre and BHF Centre of Research Excellence, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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Salamon RJ, Halbe P, Kasberg W, Bae J, Audhya A, Mahmoud AI. Parasympathetic and sympathetic axons are bundled in the cardiac ventricles and undergo physiological reinnervation during heart regeneration. iScience 2023; 26:107709. [PMID: 37674983 PMCID: PMC10477065 DOI: 10.1016/j.isci.2023.107709] [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: 03/15/2023] [Revised: 07/25/2023] [Accepted: 08/23/2023] [Indexed: 09/08/2023] Open
Abstract
Sympathetic innervation influences homeostasis, repair, and pathology in the cardiac ventricles; in contrast, parasympathetic innervation is considered to have minimal contribution and influence in the ventricles. Here, we use genetic models, whole-mount imaging, and three-dimensional modeling to define cardiac nerve architecture during development, disease, and regeneration. Our approach reveals that parasympathetic nerves extensively innervate the cardiac ventricles. Furthermore, we identify that parasympathetic and sympathetic axons develop synchronously and are bundled throughout the ventricles. We further investigate cardiac nerve remodeling in the regenerative neonatal and the non-regenerative postnatal mouse heart. Our results show that the regenerating myocardium undergoes a unique process of physiological reinnervation, where proper nerve distribution and architecture is reestablished, in stark contrast to the non-regenerating heart. Mechanistically, we demonstrate that physiological reinnervation during regeneration is dependent on collateral artery formation. Our results reveal clinically significant insights into cardiac nerve plasticity which can identify new therapies for cardiac disease.
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Affiliation(s)
- Rebecca J. Salamon
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Poorva Halbe
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - William Kasberg
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Jiyoung Bae
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK 74078, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Ahmed I. Mahmoud
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
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Salamon RJ, Halbe P, Kasberg W, Bae J, Audhya A, Mahmoud AI. Defining Cardiac Nerve Architecture During Development, Disease, and Regeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2022.12.31.522405. [PMID: 36711742 PMCID: PMC9881855 DOI: 10.1101/2022.12.31.522405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cardiac nerves regulate neonatal mouse heart regeneration and are susceptible to pathological remodeling following adult injury. Understanding cardiac nerve remodeling can lead to new strategies to promote cardiac repair. Our current understanding of cardiac nerve architecture has been limited to two-dimensional analysis. Here, we use genetic models, whole-mount imaging, and three-dimensional modeling tools to define cardiac nerve architecture and neurovascular association during development, disease, and regeneration. Our results demonstrate that cardiac nerves sequentially associate with coronary veins and arteries during development. Remarkably, our results reveal that parasympathetic nerves densely innervate the ventricles. Furthermore, parasympathetic and sympathetic nerves develop synchronously and are intertwined throughout the ventricles. Importantly, the regenerating myocardium reestablishes physiological innervation, in stark contrast to the non-regenerating heart. Mechanistically, reinnervation during regeneration is dependent on collateral artery formation. Our results reveal how defining cardiac nerve remodeling during homeostasis, disease, and regeneration can identify new therapies for cardiac disease.
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A comparative review on heart ion channels, action potentials and electrocardiogram in rodents and human: extrapolation of experimental insights to clinic. Lab Anim Res 2021; 37:25. [PMID: 34496976 PMCID: PMC8424989 DOI: 10.1186/s42826-021-00102-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 08/26/2021] [Indexed: 11/10/2022] Open
Abstract
Electrocardiogram (ECG) is a non-invasive valuable diagnostic tool that is used in clinics for investigation and monitoring of heart electrical rhythm/conduction, ischemia/injury of heart, electrolyte disturbances and agents/drugs induced cardiac toxicity. Nowadays using animal models to study heart diseases such as electrical and mechanical disturbance is common. In addition, given to ethical consideration and availability, the use of small rodents has been a top priority for cardiovascular researchers. However, extrapolation of experimental findings from the lab to the clinic needs sufficient basic knowledge of similarities and differences between heart action potential and ECG of rodents and humans in normal and disease conditions. This review compares types of human action potentials, the dominant ion currents during action potential phases, alteration in ion channels activities in channelopathies-induced arrhythmias and the ECG appearance of mouse, rat, guinea pig, rabbit and human. Also, it briefly discusses the responsiveness and alterations in ECG following some interventions such as cardiac injury and arrhythmia induction. Overall, it provides a roadmap for researchers in selecting the best animal model/species whose studies results can be translated into clinical practice. In addition, this study will also be useful to biologists, physiologists, pharmacologists, veterinarians and physicians working in the fields of comparative physiology, pharmacology, toxicology and diseases.
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An arterially perfused brainstem preparation of guinea pig to study central mechanisms of airway defense. J Neurosci Methods 2019; 317:49-60. [DOI: 10.1016/j.jneumeth.2019.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 02/07/2019] [Accepted: 02/07/2019] [Indexed: 11/18/2022]
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Mendonça MM, Santana JS, da Cruz KR, Ianzer D, Ghedini PC, Nalivaiko E, Fontes MAP, Ferreira RN, Pedrino GR, Colugnati DB, Xavier CH. Involvement of GABAergic and Adrenergic Neurotransmissions on Paraventricular Nucleus of Hypothalamus in the Control of Cardiac Function. Front Physiol 2018; 9:670. [PMID: 29915544 PMCID: PMC5994789 DOI: 10.3389/fphys.2018.00670] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 05/14/2018] [Indexed: 11/13/2022] Open
Abstract
Sympathetic premotor neurons of the paraventricular hypothalamus (PVN) play a role in hemodynamics adjustments during changes in body fluid homeostasis. However, PVN contribution to the tonic control of cardiac function remains to be systematically studied. In this study, we assessed whether GABAergic and adrenergic synapses, known for being active in the PVN, are involved in the control of cardiac function. Adult male Wistar rats (250–350 g; n = 27) were anesthetized with urethane (1.2–1.4 g/kg i.p.) and underwent catheterization of femoral artery to record blood pressure and heart rate. The femoral vein was used to inject the vasoactive agents phenylephrine (10 μg/kg) and sodium nitroprusside (10 μg/kg) and to supplement anesthesia. The cardiac left ventricle was catheterized to record left ventricular pressure and its derivative. Craniotomy allowed for injections (100 nL) into the PVN of: muscimol (20 mM), bicuculline methiodide (0.4 mM), propranolol (10 mM), isoproterenol (100 μM), phentolamine (13 mM), phenylephrine (30 nM). We found that: (i) inhibition of PVN by muscimol, reduced arterial pressure, cardiac chronotropy and inotropy; (ii) disinhibition of PVN neurons by bicuculline evoked positive chronotropy and inotropy, and increase blood pressure; (iii) PVN alpha adrenergic receptors control cardiac chronotropy and inotropy; (iv) beta adrenergic receptors of the PVN do not influence cardiac function; (v) afterload does not contribute to the PVN-evoked inotropy. Our results indicate that the modulation of the activity of PVN neurons exerted by GABAergic and adrenergic mechanisms contribute to the control of cardiac function.
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Affiliation(s)
- Michelle M Mendonça
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Joice S Santana
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Kellen R da Cruz
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Danielle Ianzer
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Paulo C Ghedini
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Eugene Nalivaiko
- Neurocardiology Laboratory, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, Australia
| | - Marco A P Fontes
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Reginaldo N Ferreira
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Gustavo R Pedrino
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Diego B Colugnati
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
| | - Carlos H Xavier
- Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiânia, Brazil
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Habecker BA, Anderson ME, Birren SJ, Fukuda K, Herring N, Hoover DB, Kanazawa H, Paterson DJ, Ripplinger CM. Molecular and cellular neurocardiology: development, and cellular and molecular adaptations to heart disease. J Physiol 2016; 594:3853-75. [PMID: 27060296 DOI: 10.1113/jp271840] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/15/2016] [Indexed: 12/12/2022] Open
Abstract
The nervous system and cardiovascular system develop in concert and are functionally interconnected in both health and disease. This white paper focuses on the cellular and molecular mechanisms that underlie neural-cardiac interactions during development, during normal physiological function in the mature system, and during pathological remodelling in cardiovascular disease. The content on each subject was contributed by experts, and we hope that this will provide a useful resource for newcomers to neurocardiology as well as aficionados.
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Affiliation(s)
- Beth A Habecker
- Department of Physiology and Pharmacology, Department of Medicine Division of Cardiovascular Medicine and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Mark E Anderson
- Johns Hopkins Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, 21287, USA
| | - Susan J Birren
- Department of Biology, Volen Center for Complex Systems, Brandeis University, Waltham, MA, 02453, USA
| | - Keiichi Fukuda
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Neil Herring
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Donald B Hoover
- Department of Biomedical Sciences, Center of Excellence in Inflammation, Infectious Disease and Immunity, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
| | - Hideaki Kanazawa
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - David J Paterson
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
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Machhada A, Marina N, Korsak A, Stuckey DJ, Lythgoe MF, Gourine AV. Origins of the vagal drive controlling left ventricular contractility. J Physiol 2016; 594:4017-30. [PMID: 26940639 PMCID: PMC4945717 DOI: 10.1113/jp270984] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 03/01/2016] [Indexed: 01/22/2023] Open
Abstract
Key points The strength, functional significance and origins of parasympathetic innervation of the left ventricle remain controversial. This study tested the hypothesis that parasympathetic control of left ventricular contractility is provided by vagal preganglionic neurones of the dorsal motor nucleus (DVMN). Under β‐adrenoceptor blockade combined with spinal cord (C1) transection (to remove sympathetic influences), systemic administration of atropine increased left ventricular contractility in rats anaesthetized with urethane, confirming the existence of a tonic inhibitory muscarinic influence on cardiac inotropy. Increased left ventricular contractility in anaesthetized rats was observed when DVMN neurones were silenced. Functional neuroanatomical mapping revealed that vagal preganglionic neurones that have an impact on left ventricular contractility are located in the caudal region of the left DVMN. These neurones provide functionally significant parasympathetic control of left ventricular inotropy.
Abstract The strength, functional significance and origins of direct parasympathetic innervation of the left ventricle (LV) remain controversial. In the present study we used an anaesthetized rat model to first confirm the presence of tonic inhibitory vagal influence on LV inotropy. Using genetic neuronal targeting and functional neuroanatomical mapping we tested the hypothesis that parasympathetic control of LV contractility is provided by vagal preganglionic neurones located in the dorsal motor nucleus (DVMN). It was found that under systemic β‐adrenoceptor blockade (atenolol) combined with spinal cord (C1) transection (to remove sympathetic influences), intravenous administration of atropine increases LV contractility in rats anaesthetized with urethane, but not in animals anaesthetized with pentobarbital. Increased LV contractility in rats anaesthetized with urethane was also observed when DVMN neurones targeted bilaterally to express an inhibitory Drosophila allatostatin receptor were silenced by application of an insect peptide allatostatin. Microinjections of glutamate and muscimol to activate or inhibit neuronal cell bodies in distinct locations along the rostro‐caudal extent of the left and right DVMN revealed that vagal preganglionic neurones, which have an impact on LV contractility, are located in the caudal region of the left DVMN. Changes in LV contractility were only observed when this subpopulation of DVMN neurones was activated or inhibited. These data confirm the existence of a tonic inhibitory muscarinic influence on LV contractility. Activity of a subpopulation of DVMN neurones provides functionally significant parasympathetic control of LV contractile function. The strength, functional significance and origins of parasympathetic innervation of the left ventricle remain controversial. This study tested the hypothesis that parasympathetic control of left ventricular contractility is provided by vagal preganglionic neurones of the dorsal motor nucleus (DVMN). Under β‐adrenoceptor blockade combined with spinal cord (C1) transection (to remove sympathetic influences), systemic administration of atropine increased left ventricular contractility in rats anaesthetized with urethane, confirming the existence of a tonic inhibitory muscarinic influence on cardiac inotropy. Increased left ventricular contractility in anaesthetized rats was observed when DVMN neurones were silenced. Functional neuroanatomical mapping revealed that vagal preganglionic neurones that have an impact on left ventricular contractility are located in the caudal region of the left DVMN. These neurones provide functionally significant parasympathetic control of left ventricular inotropy.
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Affiliation(s)
- Asif Machhada
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK.,UCL Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, WC1E 6DD, UK
| | - Nephtali Marina
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Alla Korsak
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Daniel J Stuckey
- UCL Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, WC1E 6DD, UK
| | - Mark F Lythgoe
- UCL Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, London, WC1E 6DD, UK
| | - Alexander V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
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Abstract
There is continuing belief that cardiac parasympathetic postganglionic fibres are sparse or absent from the ventricles. This review of the literature shows that the supposition is a myth. Early studies considered that fine silver-stained fibres coursing amongst ventricle myocardial cells were most likely cardiac parasympathetic postganglionic fibres. The conclusions were later supported by acetyl cholinesterase staining using a method that appeared not to be associated with noradrenaline nerve fibres. The conclusion is critically examined in the light of several recent histological studies using the acetyl cholinesterase method and also a more definitive technique (CHAT), that suggest a widespread location of parasympathetic ganglia and a relatively dense parasympathetic innervation of ventricular muscle in a range of mammals including man. The many studies demonstrating acetylcholine release in the ventricle on vagal nerve stimulation and a high density of acetylcholine M2 receptors is in accord with this as are tests of ventricular performance from many physiological studies. Selective control of cardiac functions by anatomically segregated parasympathetic ganglia is discussed. It is argued that the influence of vagal stimulation on ventricular myocardial action potential refractory period, duration, force and rhythm is evidence that vagal fibres have close apposition to myocardial fibres. This is supported by clear evidence of accentuated antagonism between sympathetic activity and vagal activity in the ventricle and also by direct effects of vagal activity independent of sympathetic activity. The idea of differential control of atrial and ventricular physiology by vagal C and vagal B preganglionic fibres is examined as well as differences in chemical phenotypes and their function. The latter is reflected in medullary and supramedullary control. Reference is made to the importance of this knowledge to understanding the normal physiology of cardiac autonomic control and significance to pathology.
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Affiliation(s)
- J H Coote
- J. H. Coote: School of Clinical and Experimental Medicine, University of Birmingham, Birmingham B15 2TT, UK.
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Xavier CH, Beig MI, Ianzer D, Fontes MAP, Nalivaiko E. Asymmetry in the control of cardiac performance by dorsomedial hypothalamus. Am J Physiol Regul Integr Comp Physiol 2013; 304:R664-74. [PMID: 23408030 DOI: 10.1152/ajpregu.00401.2012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dorsomedial hypothalamus (DMH) plays a key role in integrating cardiovascular responses to stress. We have recently reported greater heart rate responses following disinhibition of the right side of the DMH (R-DMH) in anesthetized rats and greater suppression of stress-induced tachycardia following inhibition of the R-DMH in conscious rats [both compared with similar intervention in the left DMH (L-DMH)], suggesting existence of right/left side asymmetry in controlling cardiac chronotropic responses by the DMH. The aim of the present study was to determine whether similar asymmetry is present for controlling cardiac contractility. In anesthetized rats, microinjections of the GABAA antagonist bicuculline methiodide (BMI; 40 pmol/100 nl) into the DMH-evoked increases in heart rate (HR), left ventricular pressure (LVP), myocardial contractility (LVdP/dt), arterial pressure, and respiratory rate. DMH disinhibition also precipitated multiple ventricular and supraventricular ectopic beats. DMH-induced increases in HR, LVP, LVdP/dt, and in the number of ectopic beats dependent on the side of stimulation, with R-DMH provoking larger responses. In contrast, pressor and respiratory responses did not depend on the side of stimulation. Newly described DMH-induced inotropic responses were rate-, preload- and (largely) afterload-independent; they were mediated by sympathetic cardiac pathway, as revealed by their sensitivity to β-adrenergic blockade. We conclude that recruitment of DMH neurons causes sympathetically mediated positive chronotropic and inotropic effects, and that there is an asymmetry, at the level of the DMH, in the potency to elicit these effects, with R-DMH > L-DMH.
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Affiliation(s)
- Carlos Henrique Xavier
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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11
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Modulation of respiratory sinus arrhythmia in rats with central pattern generator hardware. J Neurosci Methods 2013; 212:124-32. [DOI: 10.1016/j.jneumeth.2012.09.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 09/19/2012] [Accepted: 09/21/2012] [Indexed: 11/17/2022]
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Kawada T, Akiyama T, Shimizu S, Kamiya A, Uemura K, Sata Y, Shirai M, Sugimachi M. Central vagal activation by alpha(2) -adrenergic stimulation is impaired in spontaneously hypertensive rats. Acta Physiol (Oxf) 2012; 206:72-9. [PMID: 22463699 DOI: 10.1111/j.1748-1716.2012.02439.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 12/21/2011] [Accepted: 03/22/2012] [Indexed: 11/28/2022]
Abstract
AIM To elucidate the abnormality of vagal control in spontaneously hypertensive rats (SHR) by measuring left ventricular myocardial interstitial acetylcholine (ACh) release in response to α(2) -adrenergic stimulation as an index of in vivo vagal nerve activity. METHODS A cardiac microdialysis technique was applied to the rat left ventricle in vivo, and the effect of α(2) -adrenergic stimulation by medetomidine or electrical vagal nerve stimulation on myocardial interstitial ACh levels was examined in normotensive Wistar-Kyoto rats (WKY) and SHR under anaesthetized conditions. RESULTS Intravenous medetomidine (0.1 mg kg(-1) ) significantly increased the ACh levels in WKY (from 2.4 ± 0.6 to 4.2 ± 1.3 nmol L(-1) , P < 0.05, n = 7) but not in SHR (from 2.5 ± 0.7 to 2.7 ± 0.7 nmol L(-1) , n = 7). In contrast, electrical vagal nerve stimulation increased the ACh levels in both WKY (from 1.0 ± 0.4 to 2.9 ± 0.9 nmol L(-1) , P < 0.001, n = 6) and SHR (from 0.9 ± 0.2 to 2.2 ± 0.4 nmol L(-1) , P < 0.001, n = 6). Intravenous administration of medetomidine (0.1 mg kg(-1) ) did not affect the vagal nerve stimulation-induced ACh release in either WKY or SHR. CONCLUSION Medetomidine-induced central vagal activation was impaired in SHR, whereas peripheral vagal control of ACh release was preserved. In addition to abnormal sympathetic control, vagal control by the central nervous system may be impaired in SHR.
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Affiliation(s)
- T. Kawada
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - T. Akiyama
- Department of Cardiac Physiology; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - S. Shimizu
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - A. Kamiya
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - K. Uemura
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - Y. Sata
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - M. Shirai
- Department of Cardiac Physiology; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
| | - M. Sugimachi
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center Research Institute; Osaka; Japan
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Controlling the contractile strength of engineered cardiac muscle by hierarchal tissue architecture. Biomaterials 2012; 33:5732-41. [PMID: 22594976 DOI: 10.1016/j.biomaterials.2012.04.043] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 04/17/2012] [Indexed: 11/23/2022]
Abstract
The heart is a muscular organ with a wrapping, laminar structure embedded with neural and vascular networks, collagen fibrils, fibroblasts, and cardiac myocytes that facilitate contraction. We hypothesized that these non-muscle components may have functional benefit, serving as important structural alignment cues in inter- and intra-cellular organization of cardiac myocytes. Previous studies have demonstrated that alignment of engineered myocardium enhances calcium handling, but how this impacts actual force generation remains unclear. Quantitative assays are needed to determine the effect of alignment on contractile function and muscle physiology. To test this, micropatterned surfaces were used to build 2-dimensional myocardium from neonatal rat ventricular myocytes with distinct architectures: confluent isotropic (serving as the unaligned control), confluent anisotropic, and 20 μm spaced, parallel arrays of multicellular myocardial fibers. We combined image analysis of sarcomere orientation with muscular thin film contractile force assays in order to calculate the peak sarcomere-generated stress as a function of tissue architecture. Here we report that increasing peak systolic stress in engineered cardiac tissues corresponds with increasing sarcomere alignment. This change is larger than would be anticipated from enhanced calcium handling and increased uniaxial alignment alone. These results suggest that boundary conditions (heterogeneities) encoded in the extracellular space can regulate muscle tissue function, and that structural organization and cytoskeletal alignment are critically important for maximizing peak force generation.
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Fidelis-de-Oliveira P, Werneck-de-Castro JPS, Pinho-Ribeiro V, Shalom BCM, Nascimento-Silva JH, Costa e Souza RH, Cruz IS, Rangel RR, Goldenberg RCS, Campos-de-Carvalho AC. Soluble factors from multipotent mesenchymal stromal cells have antinecrotic effect on cardiomyocytes in vitro and improve cardiac function in infarcted rat hearts. Cell Transplant 2012; 21:1011-21. [PMID: 22305373 DOI: 10.3727/096368911x623916] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The mechanisms underlying the functional improvement after injection of multipotent mesenchymal stromal cells (MSCs) in infarcted hearts remain incompletely understood. The aim of this study was to investigate if soluble factors secreted by MSCs promote cardioprotection. For this purpose, conditioned medium (CM) was obtained after three passages from MSC cultures submitted to 72 h of conditioning in serum-free DMEM under normoxia (NCM) or hypoxia (HCM) conditions. CM was concentrated 25-fold before use (NCM-25X, concentrated normoxia conditioned medium; HCM-25X, concentrated hypoxia conditioned medium). The in vitro cardioprotection was evaluated in neonatal ventricular cardiomyocytes by quantifying apoptosis after 24 h of serum deprivation associated with hypoxia (1% O(2)) in the absence or presence of NCM and HCM (nonconcentrated and 25-fold concentrated). The in vivo cardioprotection of HCM was tested in a model of myocardial infarction (MI) induced in Wistar male rats by permanent left coronary occlusion. Intramyocardial injection of HCM-25X (n = 14) or nonconditioned DMEM (n = 16) was performed 3 h after coronary occlusion and cardiac function was evaluated 19-21 days after medium injection. Cardiac function was evaluated by electro- and echocardiogram, left ventricular catheterization, and treadmill test. The in vitro results showed that HCM was able to decrease cardiomyocyte necrosis. The in vivo results showed that HCM-25X administered 3 h after AMI was able to promote a significant reduction (35%) in left ventricular end-diastolic pressure and improvement of cardiac contractility (15%) and relaxation (12%). These results suggest that soluble factors released in vitro by MSCs are able to promote cardioprotection in vitro and improve cardiac function in vivo.
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Wieling W, Rozenberg J, Go-Schön IK, Karemaker JM, Westerhof BE, Jardine DL. Hemodynamic mechanisms underlying prolonged post-faint hypotension. Clin Auton Res 2011; 21:405-13. [PMID: 21796352 PMCID: PMC3210950 DOI: 10.1007/s10286-011-0134-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 06/09/2011] [Indexed: 11/29/2022]
Abstract
OBJECTIVE During hypotension induced by tilt-table testing, low presyncopal blood pressure (BP) usually recovers within 1 min after tilt back. However, in some patients prolonged post faint hypotension (PPFH) is observed. We assessed the hemodynamics underlying PPFH in a retrospective study. METHODS Seven patients (2 females, aged 31-72 years) experiencing PPFH were studied. PPFH was defined as a systolic BP below 85 mmHg for at least 2 min after tilt back. In 6 out of 7 presyncope was provoked by 0.4 mg sublingual NTG, administered in the 60° head-up tilt position following head-up tilt for 20 min. Continuous BP was monitored and stroke volume (SV) was computed from pressure pulsations. Cardiac output (CO) was calculated from SV × heart rate (HR); and total peripheral resistance (TPR) from mean BP/CO. Left ventricular contractility was estimated by dP/dt (max) of finger pressure pulse. RESULTS Systolic BP (SYS), diastolic BP (DIAS) and HR during PPFH were lower compared to baseline: SYS 75 ± 14 versus 121 ± 18 mmHg, DIAS 49 ± 9 versus 71 ± 9 mmHg and HR 52 ± 14 versus 67 ± 12 beats/min (p < 0.05). Marked hypotension was associated with a 47% fall in CO 3.1 ± 0.6 versus 5.9 ± 1.3 L/min (p < 0.05) and decreases in dP/dt, 277 ± 77 versus 759 ± 160 mmHg/s (p < 0.05). The difference in TPR was not significant 1.1 ± 0.3 versus 1.0 ± 0.3 MU (p = 0.229). In four patients, we attempted to treat PPFH by 30° head-down tilt. This intervention increased SYS only slightly (to 89 ± 12 mmHg). INTERPRETATION PPFH seems to be mediated by severe cardiac depression.
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Affiliation(s)
- Wouter Wieling
- Department of Medicine, Academic Medical Centre, University of Amsterdam, The Netherlands.
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Abstract
The methods used to assess cardiac parasympathetic (cardiovagal) activity and its effects on the heart in both humans and animal models are reviewed. Heart rate (HR)-based methods include measurements of the HR response to blockade of muscarinic cholinergic receptors (parasympathetic tone), beat-to-beat HR variability (HRV) (parasympathetic modulation), rate of post-exercise HR recovery (parasympathetic reactivation), and reflex-mediated changes in HR evoked by activation or inhibition of sensory (afferent) nerves. Sources of excitatory afferent input that increase cardiovagal activity and decrease HR include baroreceptors, chemoreceptors, trigeminal receptors, and subsets of cardiopulmonary receptors with vagal afferents. Sources of inhibitory afferent input include pulmonary stretch receptors with vagal afferents and subsets of visceral and somatic receptors with spinal afferents. The different methods used to assess cardiovagal control of the heart engage different mechanisms, and therefore provide unique and complementary insights into underlying physiology and pathophysiology. In addition, techniques for direct recording of cardiovagal nerve activity in animals; the use of decerebrate and in vitro preparations that avoid confounding effects of anesthesia; cardiovagal control of cardiac conduction, contractility, and refractoriness; and noncholinergic mechanisms are described. Advantages and limitations of the various methods are addressed, and future directions are proposed.
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Affiliation(s)
- Mark W Chapleau
- The Cardiovascular Center and Department of Internal Medicine, The University of Iowa Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USA.
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Wipfler P, Pilz G, Broussalis E, Golaszewski SM, Kunz A, Trinka E, Kraus J. Acute pulmonary edema caused by a multiple sclerosis relapse. J Neurol 2011; 258:1176-9. [DOI: 10.1007/s00415-011-5903-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/30/2010] [Accepted: 01/03/2011] [Indexed: 12/01/2022]
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