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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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Jalil M, Coverdell TC, Gutierrez VA, Crook ME, Shi J, Stornetta DS, Schwalbe DC, Abbott SBG, Campbell JN. Molecular Disambiguation of Heart Rate Control by the Nucleus Ambiguus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.16.571991. [PMID: 38168262 PMCID: PMC10760142 DOI: 10.1101/2023.12.16.571991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The nucleus ambiguus (nAmb) provides parasympathetic control of cardiorespiratory functions as well as motor control of the upper airways and striated esophagus. A subset of nAmb neurons innervates the heart through the vagus nerve to control cardiac function at rest and during key autonomic reflexes such as the mammalian diving reflex. These cardiovagal nAmb neurons may be molecularly and anatomically distinct, but how they differ from other nAmb neurons in the adult brain remains unclear. We therefore classified adult mouse nAmb neurons based on their genome-wide expression profiles, innervation of cardiac ganglia, and ability to control HR. Our integrated analysis of single-nucleus RNA-sequencing data predicted multiple molecular subtypes of nAmb neurons. Mapping the axon projections of one nAmb neuron subtype, Npy2r-expressing nAmb neurons, showed that they innervate cardiac ganglia. Optogenetically stimulating all nAmb vagal efferent neurons dramatically slowed HR to a similar extent as selectively stimulating Npy2r+ nAmb neurons, but not other subtypes of nAmb neurons. Finally, we trained mice to perform voluntary underwater diving, which we use to show Npy2r+ nAmb neurons are activated by the diving response, consistent with a cardiovagal function for this nAmb subtype. These results together reveal the molecular organization of nAmb neurons and its control of heart rate.
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Affiliation(s)
- Maira Jalil
- Department of Biology, University of Virginia, Charlottesville, VA
| | | | | | - Maisie E. Crook
- Department of Biology, University of Virginia, Charlottesville, VA
| | - Jiachen Shi
- Department of Biology, University of Virginia, Charlottesville, VA
| | | | - Dana C. Schwalbe
- Department of Biology, University of Virginia, Charlottesville, VA
| | | | - John N. Campbell
- Department of Biology, University of Virginia, Charlottesville, VA
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Dusi V, De Ferrari GM, Schwartz PJ. There are 100 ways by which the sympathetic nervous system can trigger life-threatening arrhythmias. Eur Heart J 2020; 41:2180-2182. [DOI: 10.1093/eurheartj/ehz950] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Abstract
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Affiliation(s)
- Veronica Dusi
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milan, Italy
| | | | - Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milan, Italy
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Dusi V, De Ferrari GM, Pugliese L, Schwartz PJ. Cardiac Sympathetic Denervation in Channelopathies. Front Cardiovasc Med 2019; 6:27. [PMID: 30972341 PMCID: PMC6443634 DOI: 10.3389/fcvm.2019.00027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/01/2019] [Indexed: 12/24/2022] Open
Abstract
Left cardiac sympathetic denervation (LCSD) is a surgical antiadrenergic intervention with a strong antiarrhythmic effect, supported by preclinical as well as clinical data. The mechanism of action of LCSD in structurally normal hearts with increased arrhythmic susceptibility (such as those of patients with channelopathies) is not limited to the antagonism of acute catecholamines release in the heart. LCSD also conveys a strong anti-fibrillatory action that was first demonstrated over 40 years ago and provides the rationale for its use in almost any cardiac condition at increased risk of ventricular fibrillation. The molecular mechanisms involved in the final antiarrhythmic effect of LCSD turned out to be much broader than anticipated. Beside the vagotonic effect at different levels of the neuraxis, other new mechanisms have been recently proposed, such as the antagonism of neuronal remodeling, the antagonism of neuropeptide Y effects, and the correction of neuronal nitric oxide synthase (nNOS) imbalance. The beneficial effects of LCSD have never been associated with a detectable deterioration of cardiac performance. Finally, patients express a high degree of satisfaction with the procedure. In this review, we focus on the rationale, results and our personal approach to LCSD in patients with channelopathies such as long QT syndrome and catecholaminergic polymorphic ventricular tachycardia.
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Affiliation(s)
- Veronica Dusi
- Department of Molecular Medicine, Section of Cardiology, University of Pavia, Pavia, Italy
- Cardiac Intensive Care Unit, Arrhythmia and Electrophysiology and Experimental Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Gaetano Maria De Ferrari
- Department of Molecular Medicine, Section of Cardiology, University of Pavia, Pavia, Italy
- Cardiac Intensive Care Unit, Arrhythmia and Electrophysiology and Experimental Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Luigi Pugliese
- Unit of General Surgery 2, Department of Surgery, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Peter J. Schwartz
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
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Meng F, Han J, Wang J, Zhang H, Xu C, Meng X. The gender-specific expression of neuropeptide Y and neuropeptide Y receptors in human atrial tissue during cardiopulmonary bypass surgery. J Thorac Dis 2019; 10:6563-6568. [PMID: 30746201 DOI: 10.21037/jtd.2018.11.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Cardiac sympathetic nervous system is usually activated in cardiopulmonary bypass (CPB) surgery, accompanied by excessive release of norepinephrine (NE). Neuropeptide Y (NPY) has been shown to regulate NE release in the terminal of sympathetic fiber, which is a target for regulating heart function. The expression of NPY and NPY receptor (NPYR) genes in the human atrial tissues during CPB in cardiac surgery was investigated in the present study. Methods A few discarded atrial tissues before and after CPB were collected in 22 patients with rheumatic cardiac valve diseases. The transcriptional levels of NPY and NPYRs were monitored by real-time quantitative polymerase chain reaction (RT-qPCR) method. Moreover, the correlation between the mRNA levels of NPY/NPYRs and the clinical data were investigated in detail. Results The mRNA levels of NPY Y1 and NPY Y5 genes were statistically attenuated in male patients after CPB. Conversely, the expression of NPY, NPY Y1 and NPY Y5 genes were enhanced in female patients. Correlation analysis suggested that there was a significant negative correlation between cardiac ejection fraction (EF) after CPB with the atrial transcriptional level of NPY in male patients. Conclusions These results suggested that the expression of NPY/NPYRs in human atrial tissue during CPB was gender specific and activated NPY signaling was only identified in female patients. The elevated expression level of NPY in male patients was correlated with lower cardiac EF after CPB.
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Affiliation(s)
- Fei Meng
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Jie Han
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Jiangang Wang
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Haibo Zhang
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Chunlei Xu
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
| | - Xu Meng
- Cardiac Valve Center, Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China
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Tan CMJ, Green P, Tapoulal N, Lewandowski AJ, Leeson P, Herring N. The Role of Neuropeptide Y in Cardiovascular Health and Disease. Front Physiol 2018; 9:1281. [PMID: 30283345 PMCID: PMC6157311 DOI: 10.3389/fphys.2018.01281] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/24/2018] [Indexed: 12/20/2022] Open
Abstract
Neuropeptide Y (NPY) is an abundant sympathetic co-transmitter, widely found in the central and peripheral nervous systems and with diverse roles in multiple physiological processes. In the cardiovascular system it is found in neurons supplying the vasculature, cardiomyocytes and endocardium, and is involved in physiological processes including vasoconstriction, cardiac remodeling, and angiogenesis. It is increasingly also implicated in cardiovascular disease pathogenesis, including hypertension, atherosclerosis, ischemia/infarction, arrhythmia, and heart failure. This review will focus on the physiological and pathogenic role of NPY in the cardiovascular system. After summarizing the NPY receptors which predominantly mediate cardiovascular actions, along with their signaling pathways, individual disease processes will be considered. A thorough understanding of these roles may allow therapeutic targeting of NPY and its receptors.
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Affiliation(s)
- Cheryl M J Tan
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Peregrine Green
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
| | - Nidi Tapoulal
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
| | - Adam J Lewandowski
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Paul Leeson
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Neil Herring
- Department of Physiology, Anatomy and Genetics, Burdon Sanderson Cardiac Science Centre, University of Oxford, Oxford, United Kingdom
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Herring N. Autonomic control of the heart: going beyond the classical neurotransmitters. Exp Physiol 2014; 100:354-8. [PMID: 25344273 PMCID: PMC4405038 DOI: 10.1113/expphysiol.2014.080184] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 10/09/2014] [Indexed: 12/11/2022]
Abstract
Acute myocardial infarction and congestive cardiac failure are characterized by high levels of cardiac sympathetic drive. In these conditions, sympathetic neurotransmitters such as neuropeptide Y (NPY) can be released in addition to noradrenaline, and plasma levels correlate with infarct size and mortality. Even in the presence of β-blockers, NPY is able to bind to its own receptors located on cholinergic ganglia and ventricular myocytes. In this symposium report, I review the evidence that NPY can inhibit acetylcholine release during vagus nerve stimulation and limit the subsequent bradycardia. I also present preliminary, as yet unpublished data, demonstrating that NPY may be pro-arrhythmic by directly influencing ventricular electrophysiology. Targeting NPY receptors pharmacologically may therefore be a useful therapeutic strategy both to reduce heart rate and to prevent arrhythmias in the setting of myocardial infarction and chronic heart failure. Such medications would be expected to act synergistically with β-blockers, angiotensin-converting enzyme inhibitors and implantable cardiac devices, such as defibrillators and vagus nerve stimulators.
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Affiliation(s)
- Neil Herring
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK
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Abstract
Autonomic cardiac neurons have a common origin in the neural crest but undergo distinct developmental differentiation as they mature toward their adult phenotype. Progenitor cells respond to repulsive cues during migration, followed by differentiation cues from paracrine sources that promote neurochemistry and differentiation. When autonomic axons start to innervate cardiac tissue, neurotrophic factors from vascular tissue are essential for maintenance of neurons before they reach their targets, upon which target-derived trophic factors take over final maturation, synaptic strength and postnatal survival. Although target-derived neurotrophins have a central role to play in development, alternative sources of neurotrophins may also modulate innervation. Both developing and adult sympathetic neurons express proNGF, and adult parasympathetic cardiac ganglion neurons also synthesize and release NGF. The physiological function of these “non-classical” cardiac sources of neurotrophins remains to be determined, especially in relation to autocrine/paracrine sustenance during development.
Cardiac autonomic nerves are closely spatially associated in cardiac plexuses, ganglia and pacemaker regions and so are sensitive to release of neurotransmitter, neuropeptides and trophic factors from adjacent nerves. As such, in many cardiac pathologies, it is an imbalance within the two arms of the autonomic system that is critical for disease progression. Although this crosstalk between sympathetic and parasympathetic nerves has been well established for adult nerves, it is unclear whether a degree of paracrine regulation occurs across the autonomic limbs during development. Aberrant nerve remodeling is a common occurrence in many adult cardiovascular pathologies, and the mechanisms regulating outgrowth or denervation are disparate. However, autonomic neurons display considerable plasticity in this regard with neurotrophins and inflammatory cytokines having a central regulatory function, including in possible neurotransmitter changes. Certainly, neurotrophins and cytokines regulate transcriptional factors in adult autonomic neurons that have vital differentiation roles in development. Particularly for parasympathetic cardiac ganglion neurons, additional examinations of developmental regulatory mechanisms will potentially aid in understanding attenuated parasympathetic function in a number of conditions, including heart failure.
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Affiliation(s)
- Wohaib Hasan
- Knight Cardiovascular Institute; Oregon Health & Science University; Portland, OR USA
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Oliveira R, Vitor da Costa M, Pedro R, Polito M, Avelar A, Cyrino E, Nakamura F. Acute cardiac autonomic responses after a bout of resistance exercise. Sci Sports 2012. [DOI: 10.1016/j.scispo.2011.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bkaily G, Avedanian L, Al-Khoury J, Ahmarani L, Perreault C, Jacques D. Receptors and ionic transporters in nuclear membranes: new targets for therapeutical pharmacological interventions. Can J Physiol Pharmacol 2012; 90:953-65. [DOI: 10.1139/y2012-077] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Work from our group and other laboratories showed that the nucleus could be considered as a cell within a cell. This is based on growing evidence of the presence and role of nuclear membrane G-protein coupled receptors and ionic transporters in the nuclear membranes of many cell types, including vascular endothelial cells, endocardial endothelial cells, vascular smooth muscle cells, cardiomyocytes, and hepatocytes. The nuclear membrane receptors were found to modulate the functioning of ionic transporters at the nuclear level, and thus contribute to regulation of nuclear ionic homeostasis. Nuclear membranes of the mentioned types of cells possess the same ionic transporters; however, the type of receptors is cell-type dependent. Regulation of cytosolic and nuclear ionic homeostasis was found to be dependent upon a tight crosstalk between receptors and ionic transporters of the plasma membranes and those of the nuclear membrane. This crosstalk seems to be the basis for excitation–contraction coupling, excitation–secretion coupling, and excitation – gene expression coupling. Further advancement in this field will certainly shed light on the role of nuclear membrane receptors and transporters in health and disease. This will in turn enable the successful design of a new class of drugs that specifically target such highly vital nuclear receptors and ionic transporters.
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Affiliation(s)
- Ghassan Bkaily
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
| | - Levon Avedanian
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
| | - Johny Al-Khoury
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
| | - Lena Ahmarani
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
| | - Claudine Perreault
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
| | - Danielle Jacques
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, QC J1H 5N4, Canada
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Xie F, Zhang R, Yang C, Xu Y, Wang N, Sun L, Liu J, Sun L, Wei R, Ai J. Long-term neuropeptide Y administration in the periphery induces abnormal baroreflex sensitivity and obesity in rats. Cell Physiol Biochem 2012; 29:111-20. [PMID: 22415080 DOI: 10.1159/000337592] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2011] [Indexed: 11/19/2022] Open
Abstract
Neuropeptide Y (NPY) is an important neuronal element involved in cardiovascular regulation. Since elevated plasma levels of NPY have been observed in numerous pathological situations, this study aimed to determine whether long-term elevated plasma concentrations of NPY could result in aberrant baroreflex sensitivity. Mini-osmotic pump containing NPY (85 μg per 30 days) was subcutaneously implanted between scapulae in male rats for 4 months. The rats treated with NPY showed the following characters compared with control group: (1) attenuated heart rate responding to the increases in mean arterial blood pressure (MABP) induced by phenylephrine, but enhanced heart rate responding to the decreases in MABP induced by sodium nitroprusside; (2) decreased protein levels of substance P (SP) and GluR2, while increased the expression of γ-aminobutyric acid A receptor (GABA(A)R) in brainstem; (3) abdominal obesity indicated by increased body weight and accumulated fat mass in peritoneal cavity; (4) significant increases in total cholesterol, triglycerides, and low density lipoprotein levels in the periphery. These findings indicate that long-term NPY administration in the periphery leads to abnormal baroreflex sensitivity due, at least in part, to the down-regulated expression of SP/GluR2 and elevated expression of GABA(A)R in both protein and RNA levels, which indicate the alternations in glutamate function and GABA action in the nucleus tractus solitarii in NPY-treated rats. Furthermore, long-term NPY administration results in abdominal obesity and dyslipidemia.
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Affiliation(s)
- Fang Xie
- Department of Pharmacology, Harbin Medical University (the State-Province Key Laboratory of Biomedicine-Pharmaceutics of China), Harbin, China
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The cardiac sympathetic co-transmitter galanin reduces acetylcholine release and vagal bradycardia: implications for neural control of cardiac excitability. J Mol Cell Cardiol 2011; 52:667-76. [PMID: 22172449 PMCID: PMC3314977 DOI: 10.1016/j.yjmcc.2011.11.016] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 11/06/2011] [Accepted: 11/28/2011] [Indexed: 02/06/2023]
Abstract
The autonomic phenotype of congestive cardiac failure is characterised by high sympathetic drive and impaired vagal tone, which are independent predictors of mortality. We hypothesize that impaired bradycardia to peripheral vagal stimulation following high-level sympathetic drive is due to sympatho-vagal crosstalk by the adrenergic co-transmitters galanin and neuropeptide-Y (NPY). Moreover we hypothesize that galanin acts similarly to NPY by reducing vagal acetylcholine release via a receptor mediated, protein kinase-dependent pathway. Prolonged right stellate ganglion stimulation (10 Hz, 2 min, in the presence of 10 μM metoprolol) in an isolated guinea pig atrial preparation with dual autonomic innervation leads to a significant (p < 0.05) reduction in the magnitude of vagal bradycardia (5 Hz) maintained over the subsequent 20 min (n = 6). Immunohistochemistry demonstrated the presence of galanin in a small number of tyrosine hydroxylase positive neurons from freshly dissected stellate ganglion tissue sections. Following 3 days of tissue culture however, most stellate neurons expressed galanin. Stellate stimulation caused the release of low levels of galanin and significantly higher levels of NPY into the surrounding perfusate (n = 6, using ELISA). The reduction in vagal bradycardia post sympathetic stimulation was partially reversed by the galanin receptor antagonist M40 after 10 min (1 μM, n = 5), and completely reversed with the NPY Y2 receptor antagonist BIIE 0246 at all time points (1 μM, n = 6). Exogenous galanin (n = 6, 50–500 nM) also reduced the heart rate response to vagal stimulation but had no effect on the response to carbamylcholine that produced similar degrees of bradycardia (n = 6). Galanin (500 nM) also significantly attenuated the release of 3H-acetylcholine from isolated atria during field stimulation (5 Hz, n = 5). The effect of galanin on vagal bradycardia could be abolished by the galanin receptor antagonist M40 (n = 5). Importantly the GalR1 receptor was immunofluorescently co-localised with choline acetyl-transferase containing neurons at the sinoatrial node. The protein kinase C inhibitor calphostin (100 nM, n = 6) abolished the effect of galanin on vagal bradycardia whilst the protein kinase A inhibitor H89 (500 nM, n = 6) had no effect. These results demonstrate that prolonged sympathetic activation releases the slowly diffusing adrenergic co-transmitter galanin in addition to NPY, and that this contributes to the attenuation in vagal bradycardia via a reduction in acetylcholine release. This effect is mediated by GalR1 receptors on vagal neurons coupled to protein kinase C dependent signalling pathways. The role of galanin may become more important following an acute injury response where galanin expression is increased.
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Stadler J, Le TP, Haas P, Nave H. Distinct effects of NPY13-36, a specific NPY Y2 agonist, in a model of rodent endotoxemia on leukocyte subsets and cytokine levels. Ann Anat 2011; 193:486-93. [PMID: 22074679 DOI: 10.1016/j.aanat.2011.10.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 10/09/2011] [Accepted: 10/10/2011] [Indexed: 11/30/2022]
Abstract
Even now, sepsis remains a major problem in modern clinical medicine, leading to systemic inflammatory response including altered leukocyte subset distribution and increased cytokine release. As immune cells are known to express NPY receptors, we investigated the effects of a specific NPY Y(2) receptor agonist (NPY(13-36)) and/or the corresponding Y(2) receptor antagonist BIIE0246 treatment on blood (by FACS analyses) and tissue (by immunohistochemistry) leukocyte subsets as well as on levels of IL-4, IL-6, IL-10, TNF-α, INF-γ (by Cytometric Bead Array) in healthy and acutely endotoxemic rats. Results show a significant decrease in blood monocytes after LPS challenge in endotoxemic control animals (by 93%), in endotoxemic NPY(13-36) treated animals (by 83%) and in endotoxemic BIIE0246 treated animals (by 88%) as compared to the corresponding healthy controls. Endotoxemic control animals showed a significant increase of TNF-α (by 98%) as compared to the healthy control group. A treatment with NPY(13-36) significantly stabilized TNF-α level in endotoxemic animals. This study indicates distinct subset- and cytokine-specific in vivo effects induced by an NPY Y(2) receptor specific treatment after a short-term LPS challenge.
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Affiliation(s)
- Jan Stadler
- Institute for Functional and Applied Anatomy, Hannover Medical School, Germany
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Abstract
Neuropeptide Y (NPY) is widely distributed in the human body and contributes to a vast number of physiological processes. Since its discovery, NPY has been implicated in metabolic regulation and, although interest in its role in central mechanisms related to food intake and obesity has somewhat diminished, the topic remains a strong focus of research concerning NPY signalling. In addition, a number of other uses for modulators of NPY receptors have been implied in a range of diseases, although the development of NPY receptor ligands has been slow, with no clinically approved receptor therapeutics currently available. Nevertheless, several interesting small molecule compounds, notably Y2 receptor antagonists, have been published recently, fueling optimism in the field. Herein we review the role of NPY in the pathophysiology of a number of diseases and highlight instances where NPY receptor signalling systems are attractive therapeutic targets.
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Affiliation(s)
- Shaun P Brothers
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, USA
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Piao FL, Yuan K, Bai GY, Han JH, Park WH, Kim SH. Different regulation of atrial ANP release through neuropeptide Y2 and Y4 receptors. J Korean Med Sci 2008; 23:1027-32. [PMID: 19119448 PMCID: PMC2610639 DOI: 10.3346/jkms.2008.23.6.1027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 02/04/2008] [Indexed: 11/20/2022] Open
Abstract
Neuropeptide Y (NPY) receptors are present in cardiac membranes. However, its physiological roles in the heart are not clear. The aim of this study was to define the direct effects of pancreatic polypeptide (PP) on atrial dynamics and atrial natriuretic peptide (ANP) release in perfused beating atria. Pancreatic polypeptides, a NPY Y(4) receptor agonist, decreased atrial contractility but was not dose-dependent. The ANP release was stimulated by PP in a dose-dependent manner. GR 23118, a NPY Y(4) receptor agonist, also increased the ANP release and the potency was greater than PP. In contrast, peptide YY (3-36) (PYY), an NPY Y(2) receptor agonist, suppressed the release of ANP with positive inotropy. NPY, an agonist for Y(1, 2, 5) receptor, did not cause any significant changes. The pretreatment of NPY (18-36), an antagonist for NPY Y(3) receptor, markedly attenuated the stimulation of ANP release by PP but did not affect the suppression of ANP release by PYY. BIIE0246, an antagonist for NPY Y(2) receptor, attenuated the suppression of ANP release by PYY. The responsiveness of atrial contractility to PP or PYY was not affected by either of the antagonists. These results suggest that NPY Y(4) and Y(2) receptor differently regulate the release of atrial ANP.
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Affiliation(s)
| | - Kuichang Yuan
- Department of Physiology, Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea
| | - Guang Yi Bai
- Department of Physiology, Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea
| | - Jeong Hee Han
- Department of Physiology, Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea
| | - Woo Hyun Park
- Department of Physiology, Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea
| | - Suhn Hee Kim
- Department of Physiology, Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea
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16
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Abstract
The traditional model of efferent cardiac noradrenaline and acetylcholine release being driven solely via brainstem integration of circulatory reflex afferent input needs to be modified in the light of the discovery of numerous local cardiac factors that impact on peripheral neuronal neurotransmitter release. These neuromodulators can be intrinsic to sympathetic ganglia or vagal neurons (such as neuronal nitric oxide synthase), act as cotransmitters between these neuronal populations (such as neuropeptide Y) or are released from the myocardium itself to act on neurons in a paracrine manner (such as natriuretic peptides). Both myocardial infarction and congestive heart failure are characterized by enhanced regulation of these neuromodulators. This review will focus on recent evidence that nitric oxide, natriuretic peptides and neuropeptide Y act by converging on neuronal cyclic nucleotide-dependent pathways to alter the autonomic phenotype in both health and disease.
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Affiliation(s)
- Neil Herring
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, Parks Road, Oxford OX1 3PT, UK
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17
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Protas L, Robinson RB. Dissecting the NPY signaling cascade between cardiac sympathetic and parasympathetic nerves. J Mol Cell Cardiol 2008; 44:470-2. [PMID: 18272171 DOI: 10.1016/j.yjmcc.2008.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2007] [Accepted: 01/02/2008] [Indexed: 01/08/2023]
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18
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Abstract
Presynaptic receptors for four families of neuropeptides will be discussed: opioids, neuropeptide Y, adrenocorticotropic hormone (ACTH), and orexins. Presynaptic receptors for the opioids (micro, delta, kappa, and ORL(1)) and neuropeptide Y (Y(2)) inhibit transmitter release from a variety of neurones, both in the peripheral and central nervous systems. These receptors, which were also identified in human tissue, are coupled to G(i/o) proteins and block voltage-dependent Ca(2+) channels, activate voltage-dependent K(+) channels, and/or interfere with the vesicle release machinery. Presynaptic receptors for ACTH (MC(2) receptors) have so far been identified almost exclusively in cardiovascular tissues from rabbits, where they facilitate noradrenaline release; they are coupled to G(s) protein and act via stimulation of adenylyl cyclase. Presynaptic receptors for orexins (most probably OX(2) receptors) have so far almost exclusively been identified in the rat and mouse brain, where they facilitate the release of glutamate and gamma-aminobutyric acid (GABA); they are most probably linked to G(q) and directly activate the vesicle release machinery or act via a transduction mechanism upstream of the release process. Agonists and antagonists at opioid receptors owe at least part of their therapeutic effects to actions on presynaptic receptors. Therapeutic drugs targeting neuropeptide Y and orexin receptors and presynaptic ACTH receptors so far are not available.
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MESH Headings
- Animals
- Humans
- Neuropeptides/metabolism
- Orexin Receptors
- Receptors, Corticotropin/drug effects
- Receptors, Corticotropin/metabolism
- Receptors, G-Protein-Coupled/drug effects
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Neuropeptide/drug effects
- Receptors, Neuropeptide/metabolism
- Receptors, Neuropeptide Y/drug effects
- Receptors, Neuropeptide Y/metabolism
- Receptors, Opioid/drug effects
- Receptors, Opioid/metabolism
- Receptors, Presynaptic/drug effects
- Receptors, Presynaptic/metabolism
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Affiliation(s)
- E Schlicker
- Institut für Pharmakologie und Toxikologie, Rheinische Friedrich-Wilhelms-Universität, Reuterstrasse 2b, 53113 Bonn, Germany.
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19
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Herring N, Lokale MN, Danson EJ, Heaton DA, Paterson DJ. Neuropeptide Y reduces acetylcholine release and vagal bradycardia via a Y2 receptor-mediated, protein kinase C-dependent pathway. J Mol Cell Cardiol 2007; 44:477-85. [PMID: 17996892 DOI: 10.1016/j.yjmcc.2007.10.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 09/30/2007] [Accepted: 10/01/2007] [Indexed: 12/16/2022]
Abstract
The co-transmitter neuropeptide Y (NPY), released during prolonged cardiac sympathetic nerve stimulation, can attenuate vagal-induced bradycardia. We tested the hypothesis that NPY reduces acetylcholine release, at similar concentrations to which it attenuates vagal bradycardia, via pre-synaptic Y2 receptors modulating a pathway that is dependent on protein kinase A (PKA) or protein kinase C (PKC). The Y2 receptor was immunofluorescently colocalized with choline acetyl-transferase containing neurons at the guinea pig sinoatrial node. The effect of NPY in the presence of various enzyme inhibitors was then tested on the heart rate response to vagal nerve stimulation in isolated guinea pig sinoatrial node/right vagal nerve preparations and also on (3)H-acetylcholine release from right atria during field stimulation. NPY reduced the heart rate response to vagal stimulation at 1, 3 and 5 Hz (significant at 100 nM and reaching a plateau at 250 nM NPY, p<0.05, n=6) but not to the stable analogue of acetylcholine, carbamylcholine (30, 60 or 90 nM, n=6) which produced similar degrees of bradycardia. The reduced vagal response was abolished by the Y2 receptor antagonist BIIE 0246 (1 microM, n=4). NPY also significantly attenuated the release of (3)H-acetylcholine during field stimulation (250 nM, n=6). The effect of NPY (250 nM) on vagal bradycardia was abolished by the PKC inhibitors calphostin C (0.1 microM, n=5) and chelerythrine chloride (25 microM, n=6) but not the PKA inhibitor H89 (0.5 microM, n=6). Conversely, the PKC activator Phorbol-12-myristate-13-acetate (0.5 microM, n=7) mimicked the effect of NPY and significantly reduced (3)H-acetylcholine release during field stimulation. These results show that NPY attenuates vagal bradycardia via a pre-synaptic decrease in acetylcholine release that appears to be mediated by a Y2 receptor pathway involving modulation of PKC.
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Affiliation(s)
- Neil Herring
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, Parks Road, Oxford University OX1 3PT, UK
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20
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Omerovic E, Råmunddal T, Lorentzon M, Nordlander M. Effects of neuropeptide Y2 receptor blockade on ventricular arrhythmias in rats with acute myocardial infarction. Eur J Pharmacol 2007; 565:138-43. [PMID: 17451678 DOI: 10.1016/j.ejphar.2007.03.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2006] [Revised: 02/21/2007] [Accepted: 03/01/2007] [Indexed: 11/17/2022]
Abstract
Excessive sympathetic activity is believed to be the key arrhythmogenic factor both in the setting of acute myocardial infarction and during chronic heart failure. The aim of this study was to evaluate the effect of neuropeptide Y2 blockade on malignant ventricular arrhythmias in rats with acute myocardial infarction. Vagotonic dose-finding study for neuropeptide Y2 receptor antagonist, (S)-N2-[2-[4-[(R,S)-5,11-dihydro-6(6h)-oxodibenz[b,e]azepin-11-yl]-1-piperazinyl]-2-oxoethyl] cylopentyl] acetyl]-N-[2-[1,2-dihydro-3,5 (4H)-dioxo-1,2-diphenyl-3H-1,2,4-triazol-4-yl]ethyl]-argininamid (AR-H05359) was conducted in guinea pigs (n=50) and rats (n=3). Induction of postinfarction arrhythmias was conducted in Sprague-Dawley rats that were randomized into 3 groups. Neuropeptide Y2 antagonist treated rats (n=7), placebo group (n=10) and amiodarone treated rats (n=8). Myocardial infarction was induced by ligation of the left coronary artery. Computerized telemetric ECG tracings were obtained continuously before induction of myocardial infarction and up to 120 min postinfarction. Occurrence of ventricular arrhythmias was analyzed according to a 10-point arrhythmia score. There was no difference in the arrhythmia scores between the neuropeptide Y2 and the saline group. The amiodarone treated animals had lower score compared to the neuropeptide Y2 and the placebo group (p<0.05). The blockade of receptors does not reduce ventricular arrhythmias in the rats with acute myocardial infarction. Further studies are needed to evaluate whether increasing vagal tonus during sympathetic activation may be valuable anti-arrhythmic strategy to prevent sudden death in patients with myocardial infarction and heart failure.
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Affiliation(s)
- Elmir Omerovic
- Wallenberg Laboratory at Sahlgrenska Academy, Göteborg University, 413 45, Gothenburg, Sweden.
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21
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Grossman P, Taylor EW. Toward understanding respiratory sinus arrhythmia: relations to cardiac vagal tone, evolution and biobehavioral functions. Biol Psychol 2006; 74:263-85. [PMID: 17081672 DOI: 10.1016/j.biopsycho.2005.11.014] [Citation(s) in RCA: 677] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2005] [Indexed: 11/16/2022]
Abstract
Respiratory sinus arrhythmia (RSA, or high-frequency heart-rate variability) is frequently employed as an index of cardiac vagal tone or even believed to be a direct measure of vagal tone. However, there are many significant caveats regarding vagal tone interpretation: 1. Respiratory parameters can confound relations between RSA and cardiac vagal tone.2. Although intraindividual relations between RSA and cardiac vagal control are often strong, interindividual associations may be modest.3. RSA measurement is profoundly influenced by concurrent levels of momentary physical activity, which can bias estimation of individual differences in vagal tone.4. RSA magnitude is affected by beta-adrenergic tone.5. RSA and cardiac vagal tone can dissociate under certain circumstances.6. The polyvagal theory contains evolution-based speculations that relate RSA, vagal tone and behavioral phenomena. We present evidence that the polyvagal theory does not accurately depict evolution of vagal control of heart-rate variability, and that it ignores the phenomenon of cardiac aliasing and disregards the evolution of a functional role for vagal control of the heart, from cardiorespiratory synchrony in fish to RSA in mammals. Unawareness of these issues can lead to misinterpretation of cardiovascular autonomic mechanisms. On the other hand, RSA has been shown to often provide a reasonable reflection of cardiac vagal tone when the above-mentioned complexities are considered. Finally, a recent hypothesis is expanded upon, in which RSA plays a primary role in regulation of energy exchange by means of synchronizing respiratory and cardiovascular processes during metabolic and behavioral change.
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Affiliation(s)
- Paul Grossman
- Department of Psychosomatic and Internal Medicine, Psychophysiology Research Laboratory, University of Basel Hospital, Hebelstrasse 2, CH-4031 Basel, Switzerland.
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22
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Ilebekk A, Björkman JA, Nordlander M. Influence of endogenous neuropeptide Y (NPY) on the sympathetic-parasympathetic interaction in the canine heart. J Cardiovasc Pharmacol 2006; 46:474-80. [PMID: 16160600 DOI: 10.1097/01.fjc.0000177986.21929.d8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to examine the sympathetic-parasympathetic interactions on heart rate through release of neuropeptide Y (NPY) and its action on prejunctional NPY Y2 receptors on vagal and sympathetic nerve fibers. In other studies on various preparations and in various organs, attenuation of transmitter release has in fact been demonstrated through activation of the NPY Y2 receptor. In the present study on anesthetized dogs we examine, however, for the first time if vagal bradycardia is attenuated by endogenous NPY released during intense cardiac sympathetic stimulation. In addition, we explore if sympathetic transmitter release and heart rate, during moderate sympathetic stimulation, are affected through this receptor system. The significance of the NPY Y2 receptor was revealed by performing experiments before and after administration of its specific receptor antagonist BIIE0246. We found that attenuation of the bradycardia during vagal nerve stimulation was dose-dependently counteracted by BIIE0246 and that the tachycardia elicited by sympathetic stimulation remained unaffected after NPY Y2 receptor blockade. Thus, endogenous NPY appears to attenuate vagal bradycardia by stimulating prejunctional NPY Y2 receptors on cardiac vagal nerve terminals and, less efficiently, to attenuate transmitter release and tachycardia through a feedback loop on the cardiac sympathetic nerve fibers.
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Affiliation(s)
- Arnfinn Ilebekk
- Institute for Experimental Medical Research, Ullevål University Hospital, 0407 Oslo, Norway.
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23
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Affiliation(s)
- Ullamari Pesonen
- Dept. of Pharmacology and Clinical Pharmacology, University of Turku, Itäinen Pitkäkatu 4B, FIN-20520, Turku, Finland.
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24
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Wultsch T, Painsipp E, Thoeringer CK, Herzog H, Sperk G, Holzer P. Endogenous neuropeptide Y depresses the afferent signaling of gastric acid challenge to the mouse brainstem via neuropeptide Y type Y2 and Y4 receptors. Neuroscience 2005; 136:1097-107. [PMID: 16216428 PMCID: PMC4359901 DOI: 10.1016/j.neuroscience.2005.08.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 07/29/2005] [Accepted: 08/10/2005] [Indexed: 01/04/2023]
Abstract
Vagal afferents signal gastric acid challenge to the nucleus tractus solitarii of the rat brainstem. This study investigated whether nucleus tractus solitarii neurons in the mouse also respond to gastric acid challenge and whether this chemonociceptive input is modified by neuropeptide Y acting via neuropeptide Y receptors of type Y2 or Y4. The gastric mucosa of female mice was exposed to different concentrations of HCl or saline, excitation of neurons in the nucleus tractus solitarii visualized by c-Fos immunohistochemistry, gastric emptying deduced from the gastric volume recovery, and gastric lesion formation evaluated by planimetry. Relative to saline, intragastric HCl (0.15-0.35 M) increased the number of c-Fos-expressing cells in the nucleus tractus solitarii in a concentration-dependent manner, inhibited gastric emptying but failed to cause significant hemorrhagic injury in the stomach. Mice in which the Y2 or Y4 receptor gene had been deleted responded to gastric acid challenge with a significantly higher expression of c-Fos in the nucleus tractus solitarii, the increases amounting to 39 and 31%, respectively. The HCl-induced inhibition of gastric emptying was not altered by deletion of the Y2 or Y4 receptor gene. BIIE0246 ((S)-N2-[[1-[2-[4-[(R,S)-5,11-dihydro-6(6H)-oxodibenz[b,e] azepin-11-yl]-1-piperazinyl]-2-oxoethyl]cyclopentyl] acetyl]-N-[2-[1,2-dihydro-3,5 (4H)-dioxo-1,2-diphenyl-3H-1,2,4-triazol-4-yl]ethyl]-argininamide; 0.03 mmol/kg s.c.), a Y2 receptor antagonist which does not cross the blood-brain barrier, did not modify the c-Fos response to gastric acid challenge. The Y2 receptor agonist peptide YY-(3-36) (0.1 mg/kg intraperitoneally) likewise failed to alter the gastric HCl-evoked expression of c-Fos in the nucleus tractus solitarii. BIIE0246, however, prevented the effect of peptide YY-(3-36) to inhibit gastric acid secretion as deduced from measurement of intragastric pH. The current data indicate that gastric challenge with acid concentrations that do not induce overt injury but inhibit gastric emptying is signaled to the mouse nucleus tractus solitarii. Endogenous neuropeptide Y acting via Y2 and Y4 receptors depresses the afferent input to the nucleus tractus solitarii by a presumably central site of action.
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Affiliation(s)
- T Wultsch
- Department of Experimental and Clinical Pharmacology, Medical University of Graz, Universitätsplatz 4, A-8010 Graz, Austria
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25
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Potter EK, Smith-White MA. Galanin modulates cholinergic neurotransmission in the heart. Neuropeptides 2005; 39:345-8. [PMID: 15944033 DOI: 10.1016/j.npep.2004.12.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2004] [Accepted: 12/02/2004] [Indexed: 11/22/2022]
Abstract
The role of galanin (Gal) in the modulation of cholinergic neurotransmission in the heart in wild-type (129 SvJ), and GALR1 knockout mice has been studied. The mice were anaesthetised and ventilated. Blood pressure (BP) and the increase in pulse interval evoked by stimulation of the vagus nerve (deltaPI) were recorded. Resting BP and PI were not different in control and GALR1-KO mice. In control mice an intravenous, bolus injection of Gal (0.8-13 nmol/kg; n = 4-6) attenuated the deltaPI, dose dependently from 33 +/- 7% to 78 +/- 9.5%. In GALR1-KO mice, Gal (0.8-13 nmol/kg) did not attenuate deltaPI at any dose (n = 3-4). In control mice intravenous, bolus injection of neuropeptide Y (NPY; 0.5-10 nmol/kg, n = 5-7) attenuated the deltaPI by 13 +/- 10% to 67 +/- 7% with a half time to recovery of 0.5-5 +/- 1 min. In control mice, following activation of the cardiac sympathetic nerve (10 Hz for 2 min; n = 3) the deltaPI was attenuated by 92 +/- 2% with a half time to recovery of 7 +/- 1 min. In control mice in the presence of the beta-adrenoceptor antagonist propranolol (1 mg/kg), and 1 micromol/kg BIIE0426 (an NPY Y2 receptor antagonist) the deltaPI was 57+/-3% with a half time to recovery of 2.5+/-0.5 min. In GALR1-KO mice, in the presence of propranolol and BIIE0426 there was no inhibition of deltaPI. In mice, it is proposed that both Gal and NPY contribute to the prolonged attenuation of parasympathetic slowing of the heart following activation of the cardiac sympathetic nerve.
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Affiliation(s)
- Erica K Potter
- Prince of Wales Medical Research Institute, Barker Street, Randwick, 2031 Sydney, Australia.
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26
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Lin S, Boey D, Herzog H. NPY and Y receptors: lessons from transgenic and knockout models. Neuropeptides 2004; 38:189-200. [PMID: 15337371 DOI: 10.1016/j.npep.2004.05.005] [Citation(s) in RCA: 210] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Accepted: 05/21/2004] [Indexed: 11/25/2022]
Abstract
Neuropeptide Y (NPY) in the central nervous system is a major regulator of food consumption and energy homeostasis. It also regulates blood pressure, induces anxiolysis, enhances memory retention, affects circadian rhythms and modulates hormone release. Five Y receptors (Y1, Y2, Y4, Y5 and Y6) are known to mediate the action of NPY and its two other family members, peptide YY (PYY) and pancreatic polypeptide (PP). Increased NPY signaling due to elevated NPY expression in the hypothalamus leads to the development of obesity and its related phenotypes, Type II diabetes and cardiovascular disease. Dysregulation in NPY signaling also causes alterations in bone formation, alcohol consumption and seizure susceptibility. The large number of Y receptors has made it difficult to delineate their individual contributions to these physiological processes. However, recent studies analysing NPY and Y receptor overexpressing and knockout models have started to unravel some of the different functions of these Y receptors. Particularly, the use of conditional knockout models has made it possible to pinpoint a specific function to an individual Y receptor in a particular location.
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Affiliation(s)
- Shu Lin
- Neurobiology Program, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst Sydney, NSW 2010, Australia
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27
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Baraban SC. Neuropeptide Y and epilepsy: recent progress, prospects and controversies. Neuropeptides 2004; 38:261-5. [PMID: 15337378 DOI: 10.1016/j.npep.2004.04.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2004] [Accepted: 04/24/2004] [Indexed: 10/26/2022]
Abstract
Neuropeptide Y (NPY), a 36 amino-acid member of the pancreatic polypeptide family, has received considerable attention in recent years as an endogenous modulator of epileptic activity. Prominently expressed in brain regions involved in seizure generation and propagation, NPY can exert powerful effects on synaptic transmission. Here, we discuss the anti-epileptic actions of NPY and receptor subtypes responsible.
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Affiliation(s)
- S C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
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28
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Abstract
A complex system has evolved to regulate food intake and to maintain energy homeostasis. A series of short-term hormonal and neural signals that derive from the gastrointestinal tract, such as cholecystokinin (CCK), pancreatic polypeptide (PP) and peptide YY-(3-36), recently discovered to regulate meal size. Others such as ghrelin initiate meals, and insulin and leptin, together with circulating nutrients, indicate long-term energy stores. All these signals act on central nervous system sites which converge on the hypothalamus, an area that contains a large number of peptide and other neurotransmitters that influence food intake with neuropeptide Y (NPY) being one of the most prominent ones. Five Y receptors are known which mediate the action of neuropeptide Y and its two other family members, peptide YY and pancreatic polypeptide. Elevated neuropeptide Y expression in the hypothalamus leads to the development of obesity and its related phenotypes, Type II diabetes and cardiovascular disease. The limited availability of specific pharmacological tools and the considerable number of Y receptors have made it difficult to delineate their individual contributions to the regulation of energy homeostasis. However, recent studies analysing transgenic and knockout neuropeptide Y and Y receptor mouse models have started to unravel some of the individual functions of these Y receptors potentially also helping to develop novel therapeutics for a variety of physiological disorders including obesity.
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Affiliation(s)
- Herbert Herzog
- Neurobiology Program, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW 2010, Sydney, Australia.
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29
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Schwertfeger E, Klein T, Vonend O, Oberhauser V, Stegbauer J, Rump LC. Neuropeptide Y inhibits acetylcholine release in human heart atrium by activation of Y2-receptors. Naunyn Schmiedebergs Arch Pharmacol 2004; 369:455-61. [PMID: 15103451 DOI: 10.1007/s00210-004-0930-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Accepted: 03/25/2004] [Indexed: 11/30/2022]
Abstract
Congestive heart failure and other cardiac diseases are characterized by increased activity of the sympathetic nervous system, whereas at the same time parasympathetic activity is often suppressed. Such imbalance may be a result of or at least enhanced by presynaptic inhibitory effects of sympathetic neurotransmitters on acetylcholine release. We investigated whether the sympathetic cotransmitters neuropeptide Y (NPY), norepinephrine (NE), and ATP are capable of modulating acetylcholine release in human heart atrium. Human atrial appendages were incubated with [(3)H]-choline to label cholinergic transmitter stores and placed in superfusion chambers. Electrical field stimulations (S1, S2) induced a tetrodotoxin-dependent [(3)H]-release, which was taken as an index of endogenous acetylcholine release. NE, NPY, ATP, and a P2-receptor analogue were added before S2. NPY (0.05-1.0 micromol/l) concentration dependently inhibited acetylcholine release. This effect was prevented by the NPY-Y(2)-receptor antagonist BIIE 0246 (0.1 micromol/l) but not by the NPY-Y(1)-receptor antagonist BIBP 3226 (10 micromol/l). ATP (10 micromol/l), a stable analogue ADP-beta S (3 micromol/l), and NE (1 micromol/l) had no effect on acetylcholine release. m-RNA for the NPY-receptor subtypes Y(1), Y(2), Y(4), Y(5), and y(6) was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR). The results suggest that the sympathetic neurotransmitter NPY inhibits parasympathetic neurotransmission in the human heart through activation of presynaptic Y(2)-receptors. NE and ATP seem not to play a role. Since NPY plasma levels are high in chronic heart failure patients, NPY may be one component leading to impaired parasympathetic neurotransmission in those patients.
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Affiliation(s)
- Eckhard Schwertfeger
- Department of Internal Medicine IV, University Hospital Freiburg, Freiburg, Germany
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30
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Brack KE, Coote JH, Ng GA. Interaction between direct sympathetic and vagus nerve stimulation on heart rate in the isolated rabbit heart. Exp Physiol 2003; 89:128-39. [PMID: 15109218 DOI: 10.1113/expphysiol.2003.002654] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The interaction between the effects of vagus nerve stimulation (VS) and sympathetic stimulation (SS) on intrinsic heart rate was studied in the novel innervated isolated rabbit heart preparation. The effects of background VS, at different frequencies--2 Hz (low), 5 Hz (medium), 7 Hz (high)--on the chronotropic effects of different frequencies of SS--2 Hz (low), 5 Hz (medium), 10 Hz (high)--were studied. The experiments were repeated in the reverse direction studying the effects of different levels of background SS on the chronotropic effects of different levels of VS. Background VS reduced the overall positive chronotropic effect of SS at steady state in a frequency dependent manner and the rate of increase in heart rate during low and medium SS (but not high SS) was slowed in the presence of background VS. These results suggest that pre- and postjunctional mechanisms may be involved in the sympatho-vagal interaction on heart rate. On the other hand, the chronotropic effect of VS was enhanced in the presence of background SS. Vagal stimulation appears to play a dominant role over sympathetic stimulation in chronotropic effects on the isolated heart. The innervated isolated heart preparation is a valuable model to study the complex mechanisms underlying the interaction between sympathetic and parasympathetic stimulation on cardiac function.
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Affiliation(s)
- Kieran E Brack
- Department of Physiology, Division of Medical Sciences, University of Birmingham, Birmingham, UK
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31
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32
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Smith-White MA, Iismaa TP, Potter EK. Galanin and neuropeptide Y reduce cholinergic transmission in the heart of the anaesthetised mouse. Br J Pharmacol 2003; 140:170-8. [PMID: 12967946 PMCID: PMC1574002 DOI: 10.1038/sj.bjp.0705404] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
(1) This study investigated the effects of galanin (GAL) on inhibition of cholinergic (vagal) activity in the mouse heart using control galanin knockout (GAL-KO) and GAL-1R receptor knockout (GAL-1R-KO) mice. (2) In pentobarbitone anaesthetised mice, supramaximal stimulation every 30 s of the vagus nerve innervating the heart, increased pulse interval (PI) by approximately 50 ms or decreased heart rate by approximately 100 beats min-1. This response was attenuated by intravenous administration of GAL (dose ranged from 0.8 to 13 nmol kg-1) in a dose-dependent manner. (3) In GAL-KO mice, the magnitude of inhibition of the increase in PI (DeltaPI) following a bolus dose of GAL was not different from the DeltaPI in control mice, and neuropeptide Y (NPY), previously shown to attenuate vagal inhibitory activity in mice, evoked a comparative inhibition of DeltaPI in GAL-KO mice. (4) In GAL-1R-KO mice, an intravenous, bolus injection of GAL had no inhibitory effect on vagal activity. (5) In control mice, stimulation of the sympathetic nerve at 25 V, 10 Hz for 2 min in the presence of propranolol evoked a long-lasting attenuation of DeltaPI. The inhibitory effect on DeltaPI was reduced in the presence of the NPY Y2 antagonist, BIIE0246. (6) In GAL-1R-KO mice, stimulation of the sympathetic nerve in the presence of propranolol evoked an attenuation of DeltaPI not significantly different from the response in control mice in the presence of BIIE0246. Following administration of BIIE0246 in GAL-1R-KO mice, the inhibition of DeltaPI that followed stimulation of the sympathetic nerve was abolished. (7) These findings support the view that the nerve terminals of parasympathetic neurons in the mouse heart possess both GAL-1R and NPY Y2 receptors which, when activated, reduce acetylcholine release.
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Affiliation(s)
- Margaret A Smith-White
- Prince of Wales Medical Research Institute, Prince of Wales Hospital, Barker St., Randwick 2031, Sydney, Australia
| | - Tiina P Iismaa
- Garvan Institute of Medical Research, St Vincents Hospital, Darlinghurst, Sydney, Australia
| | - Erica K Potter
- Prince of Wales Medical Research Institute, Prince of Wales Hospital, Barker St., Randwick 2031, Sydney, Australia
- Author for correspondence:
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Hyland NP, Sjöberg F, Tough IR, Herzog H, Cox HM. Functional consequences of neuropeptide Y Y 2 receptor knockout and Y2 antagonism in mouse and human colonic tissues. Br J Pharmacol 2003; 139:863-71. [PMID: 12813010 PMCID: PMC1573894 DOI: 10.1038/sj.bjp.0705298] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
1 Neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) differentially activate three Y receptors (Y(1), Y(2) and Y(4)) in mouse and human isolated colon. 2 The aim of this study was to characterise Y(2) receptor-mediated responses in colon mucosa and longitudinal smooth muscle preparations from wild type (Y(2)+/+) and knockout (Y(2)-/-) mice and to compare the former with human mucosal Y agonist responses. Inhibition of mucosal short-circuit current and increases in muscle tone were monitored in colonic tissues from Y(2)+/+ and Y(2)-/- mice+/-Y(1) ((R)-N-[[4-(aminocarbonylaminomethyl)phenyl)methyl]-N(2)-(diphenylacetyl)-argininamide-trifluoroacetate (BIBO3304) or Y(2) (S)-N(2)-[[1-[2-[4-[(R,S)-5,11-dihydro-6(6H)-oxodibenz[b,e]azepin-11-yl]-1-piperazinyl]-2-oxoethyl]cyclopentyl]acetyl]-N-[2-[1,2-dihydro-3,5(4H)-dioxo-1,2-diphenyl-3H-1,2,4-triazol-4-yl]ethyl]-argininamide (BIIE0246) antagonists. 3 Predictably, Y(2)-/- tissues were insensitive to Y(2)-preferred agonist PYY(3-36) (</=100 nM), but unexpectedly Y(4)-preferred PP responses were right-shifted probably as a consequence of elevated circulating PP levels, particularly in male Y(2)-/- mice (Sainsbury et al., 2002). 4 BIBO3304 and BIIE0246 elevated mucosal ion transport, indicating blockade of inhibitory mucosal tone in Y(2)+/+ tissue. While BIBO3304 effects were unchanged, those to BIIE0246 were absent in Y(2)-/- mucosae. Neither antagonist altered muscle tone; however, BIIE0246 blocked NPY and PYY(3-36) increases in Y(2)+/+ basal tone. BIBO3304 abolished residual Y(1)-mediated NPY responses in Y(2)-/- smooth muscle. 5 Tetrodotoxin significantly reduced BIIE0246 and PYY(3-36) effects in Y(2)+/+ mouse and human mucosae, but had no effect upon Y-agonist contractile responses, indicating that Y(2) receptors are located on submucosal, but not myenteric neurones. 6 Tonic activation of submucosal Y(2) receptors by endogenous NPY, PYY or PYY(3-36) could indirectly reduce mucosal ion transport in murine and human colon, while direct activation of Y(2) receptors on longitudinal muscle results in contraction.
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Affiliation(s)
- Niall P Hyland
- Centre for Neuroscience Research, King's College London, GKT School of Biomedical Sciences, Guy's Campus, London SE1 1UL
| | - Frida Sjöberg
- Centre for Neuroscience Research, King's College London, GKT School of Biomedical Sciences, Guy's Campus, London SE1 1UL
| | - Iain R Tough
- Centre for Neuroscience Research, King's College London, GKT School of Biomedical Sciences, Guy's Campus, London SE1 1UL
| | - Herbert Herzog
- Neurobiology Program, Garvan Institute of Medical Research, 384, Victoria Street, NSW 2010, Sydney, Australia
| | - Helen M Cox
- Centre for Neuroscience Research, King's College London, GKT School of Biomedical Sciences, Guy's Campus, London SE1 1UL
- Author for correspondence:
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Redrobe JP, Dumont Y, Herzog H, Quirion R. Neuropeptide Y (NPY) Y2 receptors mediate behaviour in two animal models of anxiety: evidence from Y2 receptor knockout mice. Behav Brain Res 2003; 141:251-5. [PMID: 12742262 DOI: 10.1016/s0166-4328(02)00374-1] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The behavioural phenotype of mice lacking neuropeptide Y (NPY) Y(2)-type receptors was assessed in two well documented animal models of anxiety: namely, the elevated plus maze and the open field. NPY Y(2)-/- mice made more entries into, and spent significantly more time on, the open arms of the elevated plus maze when compared to their wild-type Y(2)+/+ controls (P<0.001). This effect was not due to non-specific changes in locomotor activity as the number of closed arm entries did not differ between groups. In addition, NPY Y(2)-/- mice displayed increased preference for the central area of the open field when compared to Y(2)+/+ animals (P<0.01), whereas total entries did not differ between groups. This study suggests that NPY Y(2) receptors may play an inhibitory role and supports the hypothesis that Y(2) receptors are involved in the regulation of anxiety-like behaviours by NPY.
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Affiliation(s)
- John P Redrobe
- Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 LaSalle Boulevard, Montreal, Que., Canada H4H 1R3
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Abstract
The skeleton is an efficient 'servo' (feedback-controlled/steady-state) system that continuously integrates signals and responses which sustain its functions of delivering calcium while maintaining strength. In many individuals, bone mass homeostasis starts failing in midlife, leading to bone loss, osteoporosis and debilitating fractures. Recent advances, spearheaded by genetic information, offer the opportunity to stop or reverse this downhill course.
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Affiliation(s)
- Shun-ichi Harada
- Department of Bone Biology & Osteoporosis Research, Merck Research Laboratories, West Point, Pennsylvania 19002, USA
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Berglund MM, Hipskind PA, Gehlert DR. Recent developments in our understanding of the physiological role of PP-fold peptide receptor subtypes. Exp Biol Med (Maywood) 2003; 228:217-44. [PMID: 12626767 DOI: 10.1177/153537020322800301] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The three peptides pancreatic polypeptide (PP), peptide YY (PYY), and neuropeptide Y (NPY) share a similar structure known as the PP-fold. There are four known human G-protein coupled receptors for the PP-fold peptides, namely Y1, Y2, Y4, and Y5, each of them being able to bind at least two of the three endogenous ligands. All three peptides are found in the circulation acting as hormones. Although NPY is only released from neurons, PYY and PP are primarily found in endocrine cells in the gut, where they exert such effects as inhibition of gall bladder secretion, gut motility, and pancreatic secretion. However, when PYY is administered in an experimental setting to animals, cloned receptors, or tissue preparations, it can mimic the effects of NPY in essentially all studies, making it difficult to study the effects of PP-fold peptides and to delineate what receptor and peptide accounts for a particular effect. Initial studies with transgenic animals confirmed the well-established action of NPY on metabolism, food-intake, vascular systems, memory, mood, neuronal excitability, and reproduction. More recently, using transgenic techniques and novel antagonists for the Y1, Y2, and Y5 receptors, NPY has been found to be a key player in the regulation of ethanol consumption and neuronal development.
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Affiliation(s)
- Magnus M Berglund
- Eli Lilly and Company, Lilly Research Laboratories, Indianapolis, Indiana 46285, USA
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Jönsson-Rylander AC, Nordlander M, Svindland A, Ilebekk A. Distribution of neuropeptide Y Y1 and Y2 receptors in the postmortem human heart. Peptides 2003; 24:255-62. [PMID: 12668210 DOI: 10.1016/s0196-9781(03)00041-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the present study, we present for the first time the presence and distribution of neuropeptide Y (NPY) receptors Y1 and Y2 in the human postmortem heart using specific antibodies raised against extracellular parts of the receptors. A more intensive staining against the Y2 than against the Y1 receptors was detected on both atrial and ventricular cardiomyocytes. Immunoreactivity against both receptors was identified on both conducting fibers and cardiac nerves. More vessels stained positively for the Y2 than for the Y1 receptor, but the Y1 receptors were more abundant in subendocardial than subepicardial vessels of the left ventricular wall.
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Smith-White MA, Herzog H, Potter EK. Cardiac function in neuropeptide Y Y4 receptor-knockout mice. REGULATORY PEPTIDES 2002; 110:47-54. [PMID: 12468109 DOI: 10.1016/s0167-0115(02)00160-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Autonomic control of cardiovascular function in neuropeptide Y (NPY) Y4 receptor-knockout mice was investigated using pancreatic polypeptide (PP), NPY and specific agonists and antagonists for other NPY receptors well characterised in cardiovascular function. Y4 receptor-knockout mice, anaesthetised with sodium pentobarbitone, displayed slower heart rate, indicated by a higher pulse interval and lower blood pressure compared to control mice. After vagus nerves were cut heart rate increased but was still significantly slower than in control mice. PP had no effect on blood pressure or cardiac vagal activity in either group of mice, which was consistent with earlier studies in other species. Injection of NPY evoked an increase in blood pressure but the response was significantly reduced in Y4 receptor-knockout mice compared to the controls. The reduction in pressor activity was not Y1 mediated as the selective Y1 antagonist, BIBP 3226, was effective in blocking NPY pressor activity in knockout mice. In addition, cardiac vagal inhibitory activity evoked by low doses of NPY was also reduced when compared to control responses. As N-acetyl [Leu(28, 31)] NPY 24-36 inhibited vagal activity dose dependently in both groups of mice with no difference in response at any dose, it is unlikely that this effect also is receptor mediated. We propose that the reduced vasoconstrictor and vagal inhibitory activity evoked by NPY in Y4 receptor-knockout mice is due to a lack of adrenergic tone bought about by a proposed reduction in sympathetic activity, possibly resulting from altered NPY activity secondarily affecting adrenergic transmission. We conclude that Y4 receptor deletion disrupts autonomic balance within the cardiovascular system.
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Affiliation(s)
- Margaret A Smith-White
- Prince of Wales Medical Research Institute, University of New South Wales, Barker St., Randwick, 2031 Sydney, Australia.
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Redrobe JP, Dumont Y, Quirion R. Neuropeptide Y (NPY) and depression: from animal studies to the human condition. Life Sci 2002; 71:2921-37. [PMID: 12384178 DOI: 10.1016/s0024-3205(02)02159-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neuropeptide Y (NPY) is widely distributed throughout the central nervous system (CNS) and is one of the most conserved peptides in evolution, suggesting an important role in the regulation of basic physiological functions. In addition, both pre-clinical and clinical evidence have suggested that NPY, together with its receptors, may have a direct implication in several psychiatric disorders, including depression and related illnesses. NPY-like immunoreactivity and NPY receptors are expressed throughout the brain, with varying concentrations being found throughout the limbic system. Such brain structures have been repeatedly implicated in the modulation of emotional processing, as well as in the pathogenesis of depressive disorders. This review will concentrate on the distribution of NPY, its receptors, and the putative role played by this peptide in depressive illness based on both pre-clinical and clinical evidence.
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Affiliation(s)
- John P Redrobe
- Douglas Hospital Research Centre, Department of Psychiatry, Institute of Neuroscience, Mental Health and Addiction, McGill University, 6875 LaSalle Blvd., Montreal, Quebec, Canada H4H 1R3
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