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Iskakov NG, Anikina TA, Nikolaev TI, Krylova AV, Zefirov TL. Effect of Adrenoreceptor Stimulation on Peptidergic Regulation of Cardiac Activity in Newborn Rats. Bull Exp Biol Med 2023; 176:9-13. [PMID: 38091133 DOI: 10.1007/s10517-023-05957-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Indexed: 12/19/2023]
Abstract
We studied the effect of adrenoreceptor stimulation on the frequency of spontaneous activity and amplitude-time parameters of isometric contraction of the atrial myocardial strips from newborn rats, as well as the effect of Y receptor stimulation against the background of adrenoreceptor activation. After addition of Y1,5 receptor agonist [Leu31, Pro34] NPY (10-7 M), a tendency to a decrease in the effect of β1,2-adrenoreceptor agonist isoproterenol (10-5 M) on the frequency of spontaneous activity and atrial myocardial contractility was observed. The age-related features of the effect of NPY on the frequency of spontaneous activity and contractility of myocardial strips from newborn and adult rats were revealed.
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Affiliation(s)
- N G Iskakov
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Republic of Tatarstan, Russia.
- Department of Medical and Biological Disciplines, Volga Region State University of Physical Culture, Sports and Tourism, Kazan, Republic of Tatarstan, Russia.
| | - T A Anikina
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Republic of Tatarstan, Russia
| | - T I Nikolaev
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Republic of Tatarstan, Russia
| | - A V Krylova
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Republic of Tatarstan, Russia
| | - T L Zefirov
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Republic of Tatarstan, Russia
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Sharma S, Littman R, Tompkins J, Arneson D, Contreras J, Dajani AH, Ang K, Tsanhani A, Sun X, Jay PY, Herzog H, Yang X, Ajijola OA. Tiered Sympathetic Control of Cardiac Function Revealed by Viral Tracing and Single Cell Transcriptome Profiling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.18.524575. [PMID: 36711942 PMCID: PMC9882306 DOI: 10.1101/2023.01.18.524575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The cell bodies of postganglionic sympathetic neurons innervating the heart primarily reside in the stellate ganglion (SG), alongside neurons innervating other organs and tissues. Whether cardiac-innervating stellate ganglionic neurons (SGNs) exhibit diversity and distinction from those innervating other tissues is not known. To identify and resolve the transcriptomic profiles of SGNs innervating the heart we leveraged retrograde tracing techniques using adeno-associated virus (AAV) expressing fluorescent proteins (GFP or Td-tomato) with single cell RNA sequencing. We investigated electrophysiologic, morphologic, and physiologic roles for subsets of cardiac-specific neurons and found that three of five adrenergic SGN subtypes innervate the heart. These three subtypes stratify into two subpopulations; high (NA1a) and low (NA1b and NA1c) Npy-expressing cells, exhibit distinct morphological, neurochemical, and electrophysiologic characteristics. In physiologic studies in transgenic mouse models modulating NPY signaling, we identified differential control of cardiac responses by these two subpopulations to high and low stress states. These findings provide novel insights into the unique properties of neurons responsible for cardiac sympathetic regulation, with implications for novel strategies to target specific neuronal subtypes for sympathetic blockade in cardiac disease.
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Mechanisms of Modulation of Adrenergic Regulation of Spontaneous Activity Rate and Atrial Myocardial Contractility in Early Postnatal Ontogeny in Rats. Bull Exp Biol Med 2023; 174:295-298. [PMID: 36723731 DOI: 10.1007/s10517-023-05694-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2022] [Indexed: 02/02/2023]
Abstract
We studied combined effect of the β1,2-adrenoreceptor agonist isoproterenol and the Y1,5 receptor agonist [Leu31, Pro34]neuropeptide Y on the frequency of spontaneous activity and myocardial contractility in 21- and 100-day-old rats. Isoproterenol increased the frequency of spontaneous activity and reduced the main parameters of isometric contraction of the atrial myocardium. When [Leu31, Pro34]neuropeptide Y was added, the frequency of spontaneous activity and the negative inotropic and the positive chronotropic effects of isoproterenol were reduced in 100-day-old rats. In 21-day-olds rats, a tendency to a decrease in the effect of isoproterenol was observed.
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Fengler K, Kresoja KP, Rommel KP, Rosch S, Roeder MV, Desch S, Thiele H, Lurz P. Sympathomodulation in Heart Failure with High vs. Normal Ejection Fraction. STRUCTURAL HEART : THE JOURNAL OF THE HEART TEAM 2022; 6:100073. [PMID: 37288333 PMCID: PMC10242566 DOI: 10.1016/j.shj.2022.100073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/15/2022] [Accepted: 06/27/2022] [Indexed: 06/09/2023]
Abstract
Background Despite recent advances in the treatment of heart failure with preserved ejection fraction (HFpEF), the overall outcome is poor and evidence-based therapeutic options are scarce. So far, the only evidence-based therapy in HFpEF, sodium glucose linked transporter 2 inhibitors, has only insignificant effects in patients with a high EF (EF > 60%, HEF) when compared to a normal EF (EF 50%-60%, NEF). This could be explained by different biomechanical and cellular phenotypes of HFpEF across the range of EFs rather than a uniform pathophysiology. We aimed to investigate the concept of different phenotypes in the HEF and NEF using noninvasive single-beat estimations and to observe alterations in pressure-volume relations in both groups following sympathomodulation using renal denervation (RDN). Methods Patients from a previous study on RDN in HFpEF were stratified by having HFpEF with an HEF or NEF. Single-beat estimations were used to derive arterial elastance (Ea), end-systolic elastance (Ees), and diastolic capacitance (VPED20). Results Overall, 63 patients were classified as having an HEF, and 36 patients were classified as having an NEF. Ea did not differ between the groups and was reduced at follow-up in both groups (p < 0.01). Ees was higher and VPED20 was lower in the HEF than those in the NEF. Both were changed significantly at follow-up in the HEF but not in the NEF. Ees/Ea was lower in the NEF (0.95 ± 0.22 vs 1.15 ± 0.27, p < 0.01) and was significantly increased in the NEF (by 0.08 ± 0.20, p < 0.05) but not in the HEF. Conclusions Beneficial effects of RDN were observed in the NEF and HEF, supporting the further investigation of sympathomodulating treatments for HFpEF in future trials.
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Affiliation(s)
- Karl Fengler
- Address correspondence to: Karl Fengler, MD, Department of Cardiology, Heart Center Leipzig at University of Leipzig, Strümpellstraße 39, Leipzig 04289, Germany.
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Liu YQ, Xue SM, Zhang P, Xu LN, Wang DP, Li G, Cao JM. Silica Nanoparticles Disturb Ion Channels and Transmembrane Potentials of Cardiomyocytes and Induce Lethal Arrhythmias in Mice. Int J Nanomedicine 2020; 15:7397-7413. [PMID: 33116478 PMCID: PMC7547143 DOI: 10.2147/ijn.s261692] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/08/2020] [Indexed: 12/22/2022] Open
Abstract
Background The toxicity of silica nanoparticles (SiNPs) on cardiac electrophysiology has seldom been evaluated. Methods Patch-clamp was used to investigate the acute effects of SiNP-100 (100 nm) and SiNP-20 (20 nm) on the transmembrane potentials (TMPs) and ion channels in cultured neonatal mouse ventricular myocytes. Calcium mobilization in vitro, cardiomyocyte ROS generation, and LDH leakage after exposure to SiNPs in vitro and in vivo were measured using a microplate reader. Surface electrocardiograms were recorded in adult mice to evaluate the arrhythmogenic effects of SiNPs in vivo. SiNP endocytosis was observed using transmission electron microscopy. Results Within 30 min, both SiNPs (10-8-10-6 g/mL) did not affect the resting potential and IK1 channels. SiNP-100 increased the action potential amplitude (APA) and the INa current density, but SiNP-20 decreased APA and INa density. SiNP-100 prolonged the action potential duration (APD) and decreased the Ito current density, while SiNP-20 prolonged or shortened the APD, depending on exposure concentrations and increased Ito density. Both SiNPs (10-6 g/mL) induced calcium mobilization but did not increase ROS and LDH levels and were not endocytosed within 10 min in cardiomyocytes in vitro. In vivo, SiNP-100 (4-10 mg/kg) and SiNP-20 (4-30 mg/kg) did not elevate myocardial ROS but increased LDH levels depending on dose and exposure time. The same higher dose of SiNPs (intravenously injected) induced tachyarrhythmias and lethal bradyarrhythmias within 90 min in adult mice. Conclusion SiNPs (i) exert rapid toxic effects on the TMPs of cardiomyocytes in vitro largely owing to their direct interfering effects on the INa and Ito channels and Ca2+ homeostasis but not IK1 channels and ROS levels, and (ii) induce tachyarrhythmias and lethal bradyarrhythmias in vivo. SiNP-100 is more toxic than SiNP-20 on cardiac electrophysiology, and the toxicity mechanism is likely more complicated in vivo.
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Affiliation(s)
- Ya-Qin Liu
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China
| | - Si-Meng Xue
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China
| | - Peng Zhang
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China
| | - Lin-Na Xu
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China
| | - De-Ping Wang
- Key Laboratory of Cellular Physiology at Shanxi Medical University, Ministry of Education, Department of Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, People's Republic of China
| | - Guang Li
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China
| | - Ji-Min Cao
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan 646000, People's Republic of China.,Key Laboratory of Cellular Physiology at Shanxi Medical University, Ministry of Education, Department of Physiology, Shanxi Medical University, Taiyuan, Shanxi 030001, People's Republic of China
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Kuncová J, Jirkovská A, Švíglerová J, Marková M, Meireles D, Čedíková M. Neonatal capsaicin administration impairs postnatal development of the cardiac chronotropy and inotropy in rats. Physiol Res 2016; 65:S633-S642. [PMID: 28006945 DOI: 10.33549/physiolres.933540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The present study evaluated the impact of neonatal administration of capsaicin (neurotoxin from red hot pepper used for sensory denervation) on postnatal development of the heart rate and ventricular contractility. In the rats subjected to capsaicin administration (100 mg/kg) on postnatal days 2 and 3 and their vehicle-treated controls at the ages of 10 to 90 days, function of the sympathetic innervation of the developing heart was characterized by evaluation of chronotropic responses to metipranolol and atropine, norepinephrine concentrations in the heart, and norepinephrine release from the heart atria. Sensory denervation was verified by determination of calcitonin gene-related peptide levels in the heart. Direct cytotoxic effects of capsaicin were assessed on cultured neonatal cardiomyocytes. Capsaicin-treated rats displayed higher resting heart rates, lower atropine effect, but no difference in the effect of metipranolol. Norepinephrine tissue levels and release did not differ from controls. Contraction force of the right ventricular papillary muscle was lower till the age of 60 days. Significantly reduced viability of neonatal cardiomyocytes was demonstrated at capsaicin concentration 100 micromol/l. Our study suggests that neonatal capsaicin treatment leads to impaired maturation of the developing cardiomyocytes. This effect cannot be attributed exclusively to sensory denervation of the rat heart since capsaicin acts also directly on the cardiac cells.
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Affiliation(s)
- J Kuncová
- Department of Physiology, Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.
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Putting together the clues of the everlasting neuro-cardiac liaison. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:1904-15. [PMID: 26778332 DOI: 10.1016/j.bbamcr.2016.01.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 12/22/2015] [Accepted: 01/04/2016] [Indexed: 12/17/2022]
Abstract
Starting from the late embryonic development, the sympathetic nervous system extensively innervates the heart and modulates its activity during the entire lifespan. The distribution of myocardial sympathetic processes is finely regulated by the secretion of limiting amounts of pro-survival neurotrophic factors by cardiac cells. Norepinephrine release by the neurons rapidly modulates myocardial electrophysiology, and increases the rate and force of cardiomyocyte contractions. Sympathetic processes establish direct interaction with cardiomyocytes, characterized by the presence of neurotransmitter vesicles and reduced cell-cell distance. Whether such contacts have a functional role in both neurotrophin- and catecholamine-dependent communication between the two cell types, is poorly understood. In this review we will address the effects of the sympathetic neuron activity on the myocardium and the hypothesis that the direct neuro-cardiac contact might have a key role both in norepinephrine and neurotrophin mediated signaling. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
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Galetin T, Tevoufouet EE, Sandmeyer J, Matthes J, Nguemo F, Hescheler J, Weiergräber M, Schneider T. Pharmacoresistant Cav 2·3 (E-type/R-type) voltage-gated calcium channels influence heart rate dynamics and may contribute to cardiac impulse conduction. Cell Biochem Funct 2012; 31:434-49. [PMID: 23086800 DOI: 10.1002/cbf.2918] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 11/10/2022]
Abstract
Voltage-gated Ca(2+) channels regulate cardiac automaticity, rhythmicity and excitation-contraction coupling. Whereas L-type (Cav 1·2, Cav 1·3) and T-type (Cav 3·1, Cav 3·2) channels are widely accepted for their functional relevance in the heart, the role of Cav 2·3 Ca(2+) channels expressing R-type currents remains to be elucidated. We have investigated heart rate dynamics in control and Cav 2·3-deficient mice using implantable electrocardiogram radiotelemetry and pharmacological injection experiments. Autonomic block revealed that the intrinsic heart rate does not differ between both genotypes. Systemic administration of isoproterenol resulted in a significant reduction in interbeat interval in both genotypes. It remained unaffected after administering propranolol in Cav 2·3(-|-) mice. Heart rate from isolated hearts as well as atrioventricular conduction for both genotypes differed significantly. Additionally, we identified and analysed the developmental expression of two splice variants, i.e. Cav 2·3c and Cav 2·3e. Using patch clamp technology, R-type currents could be detected in isolated prenatal cardiomyocytes and be related to R-type Ca(2+) channels. Our results indicate that on the systemic level, the pharmacologically inducible heart rate range and heart rate reserve are impaired in Cav 2·3 (-|-) mice. In addition, experiments on Langendorff perfused hearts elucidate differences in basic properties between both genotypes. Thus, Cav 2·3 does not only contribute to the cardiac autonomous nervous system but also to intrinsic rhythm propagation.
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Affiliation(s)
- Thomas Galetin
- Institute of Neurophysiology, University of Köln, Köln, Germany
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Boyden PA, Robinson RB. Potential players in the hood. J Interv Card Electrophysiol 2012; 35:1-2. [DOI: 10.1007/s10840-012-9697-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 05/22/2012] [Indexed: 10/28/2022]
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Ge F, Hu C, Hyodo E, Arai K, Zhou S, Lobdell IV H, Walewski JL, Homma S, Berk PD. Cardiomyocyte triglyceride accumulation and reduced ventricular function in mice with obesity reflect increased long chain Fatty Acid uptake and de novo Fatty Acid synthesis. J Obes 2012; 2012:205648. [PMID: 22132320 PMCID: PMC3216284 DOI: 10.1155/2012/205648] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 08/08/2011] [Accepted: 08/08/2011] [Indexed: 01/21/2023] Open
Abstract
A nonarteriosclerotic cardiomyopathy is increasingly seen in obese patients. Seeking a rodent model, we studied cardiac histology, function, cardiomyocyte fatty acid uptake, and transporter gene expression in male C57BL/6J control mice and three obesity groups: similar mice fed a high-fat diet (HFD) and db/db and ob/ob mice. At sacrifice, all obesity groups had increased body and heart weights and fatty livers. By echocardiography, ejection fraction (EF) and fractional shortening (FS) of left ventricular diameter during systole were significantly reduced. The V(max) for saturable fatty acid uptake was increased and significantly correlated with cardiac triglycerides and insulin concentrations. V(max) also correlated with expression of genes for the cardiac fatty acid transporters Cd36 and Slc27a1. Genes for de novo fatty acid synthesis (Fasn, Scd1) were also upregulated. Ten oxidative phosphorylation pathway genes were downregulated, suggesting that a decrease in cardiomyocyte ATP synthesis might explain the decreased contractile function in obese hearts.
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Affiliation(s)
- Fengxia Ge
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Chunguang Hu
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Eiichi Hyodo
- Division of Cardiology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Kotaro Arai
- Division of Cardiology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Shengli Zhou
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Harrison Lobdell IV
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - José L. Walewski
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Shunichi Homma
- Division of Cardiology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Paul D. Berk
- Division of Digestive and Liver Diseases, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
- Division of Preventive Medicine and Nutrition, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
- *Paul D. Berk:
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Thomsen MB, Wang C, Ozgen N, Wang HG, Rosen MR, Pitt GS. Accessory subunit KChIP2 modulates the cardiac L-type calcium current. Circ Res 2009; 104:1382-9. [PMID: 19461043 DOI: 10.1161/circresaha.109.196972] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Complex modulation of voltage-gated Ca2+ currents through the interplay among Ca2+ channels and various Ca(2+)-binding proteins is increasingly being recognized. The K+ channel interacting protein 2 (KChIP2), originally identified as an auxiliary subunit for K(V)4.2 and a component of the transient outward K+ channel (I(to)), is a Ca(2+)-binding protein whose regulatory functions do not appear restricted to K(V)4.2. Consequently, we hypothesized that KChIP2 is a direct regulator of the cardiac L-type Ca2+ current (I(Ca,L)). We found that I(Ca,L) density from KChIP2(-/-) myocytes is reduced by 28% compared to I(Ca,L) recorded from wild-type myocytes (P<0.05). This reduction in current density results from loss of a direct effect on the Ca2+ channel current, as shown in a transfected cell line devoid of confounding cardiac ion currents. I(Ca,L) regulation by KChIP2 was independent of Ca2+ binding to KChIP2. Biochemical analysis suggested a direct interaction between KChIP2 and the Ca(V)1.2 alpha(1C) subunit N terminus. We found that KChIP2 binds to the N-terminal inhibitory module of alpha(1C) and augments I(Ca,L) current density without increasing Ca(V)1.2 protein expression or trafficking to the plasma membrane. We propose a model in which KChIP2 impedes the N-terminal inhibitory module of Ca(V)1.2, resulting in increased I(Ca,L). In the context of recent reports that KChIP2 modulates multiple K(V) and Na(V) currents, these results suggest that KChIP2 is a multimodal regulator of cardiac ionic currents.
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Affiliation(s)
- Morten B Thomsen
- Department of Medicine, Duke University Medical Center, Box 103030 Medical Center, Durham, NC 27710, USA
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Galvez BG, Sampaolesi M, Barbuti A, Crespi A, Covarello D, Brunelli S, Dellavalle A, Crippa S, Balconi G, Cuccovillo I, Molla F, Staszewsky L, Latini R, DiFrancesco D, Cossu G. Cardiac mesoangioblasts are committed, self-renewable progenitors, associated with small vessels of juvenile mouse ventricle. Cell Death Differ 2008; 15:1417-28. [DOI: 10.1038/cdd.2008.75] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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Bhuiyan ZA, Hamdan MA, Shamsi ETA, Postma AV, Mannens MMAM, Wilde AAM, Al-Gazali L. A Novel Early Onset Lethal Form of Catecholaminergic Polymorphic Ventricular Tachycardia Maps to Chromosome 7p14-p22. J Cardiovasc Electrophysiol 2007; 18:1060-6. [PMID: 17666061 DOI: 10.1111/j.1540-8167.2007.00913.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Previously, autosomal dominant catecholaminergic polymorphic ventricular tachycardia (CPVT [1]) was mapped to chromosome 1q42-43 with identification of pathogenic mutations in RYR2. Autosomal recessive CPVT (2) was mapped to chromosome 1p13-21, leading to the identification of mutations in CASQ2. In this study, we aimed to elucidate clinical phenotypes of a new variant of CPVT (3) in an inbred Arab family and also delineate the chromosomal location of the gene causing CPVT (3). METHODS AND RESULTS In a highly inbred family, clinical symptoms of CPVT appeared early in childhood (7-12 years) and in three of the four cases, the first appearance of symptoms turned into a fatal outcome. Parents of the affected children were first-degree cousins and without any symptoms. Segregation analysis suggested an autosomal recessive inheritance. A genome-wide search using polymorphic DNA markers mapped the disease locus to a 25-Mb interval on chromosome 7p14-p22. A maximal multipoint LOD score of 3.17 was obtained at marker D7S493. Sequencing of putative candidate genes, SP4, NPY, FKBP9, FKBP14, PDE1C, and TBX20, in and around this locus, did not reveal any mutation. CONCLUSIONS We have identified a novel highly malignant autosomal recessive form of CPVT and mapped this disorder to a 25-Mb interval on chromosome 7p14-p22.
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Affiliation(s)
- Zahurul A Bhuiyan
- Department of Clinical Genetics, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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Abstract
Despite recent advances in preventing sudden cardiac death (SCD) due to cardiac arrhythmia, its incidence in the population at large has remained unacceptably high. Better understanding of the interaction among various functional, structural, and genetic factors underlying the susceptibility to, and initiation of, fatal arrhythmias is a major goal and will provide new tools for the prediction, prevention, and therapy of SCD. Here, we review the role of aberrant intracellular Ca handling, ionic imbalances associated with acute myocardial ischemia, neurohumoral changes, and genetic predisposition in the pathogenesis of SCD due to cardiac arrhythmia. Therapeutic measures to prevent SCD are also discussed.
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Affiliation(s)
- Michael Rubart
- Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, Indiana 46202-5225, USA.
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Kuncová J, Svíglerová J, Tonar Z, Slavíková J. Heterogenous changes in neuropeptide Y, norepinephrine and epinephrine concentrations in the hearts of diabetic rats. Auton Neurosci 2005; 121:7-15. [PMID: 15955747 DOI: 10.1016/j.autneu.2005.05.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 04/24/2005] [Accepted: 05/01/2005] [Indexed: 11/25/2022]
Abstract
The changes in concentrations of neuropeptide Y (NPY), norepinephrine and epinephrine were investigated in the rat hearts 1, 2, 4, 6, 9 and 12 months after administration of streptozotocin (STZ; 65 mg/kg i.v.). About 30% of diabetic animals displayed symptoms of partial spontaneous recovery, i.e. decreasing blood glucose levels and increasing insulin concentrations in the plasma and pancreas. NPY concentrations in the atria of diabetic rats did not differ from those in age-matched control rats 1, 2, 4, 6 months in the right atria and even 9 months after STZ in the left atria. However, uncompensated diabetes led to a significant decrease in NPY levels 9 and 12 months after STZ administration in the right and left atria, respectively. In the ventricles, NPY concentrations were significantly decreased 6 months after the onset of diabetes. Interestingly, partial spontaneous recovery of diabetes was associated with increased NPY levels in the atria. Myocardial norepinephrine concentrations increased 1 month after STZ and then declined reaching approximately 60% of the respective control values 12 months after the onset of the disease. Partial spontaneous recovery of diabetes had no effect on norepinephrine concentrations. Myocardial epinephrine concentrations did not differ from those found in controls till month 9 of the disease and they became significantly lower at month 12. Partial recovery of diabetes resulted in epinephrine concentrations not differing from the control values at month 12 of diabetes. Regarding to preferential localization of norepinephrine in the sympathetic postganglionic fibers and that of NPY also in intrinsic ganglion neurons, intrinsic neuronal circuits seem to be less susceptible to STZ-induced damage than extrinsic nerves and they might be able to recover after amelioration of diabetes.
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Affiliation(s)
- Jitka Kuncová
- Department of Physiology, Faculty of Medicine, Charles University, Lidická 1, 301 66 Plzen, Czech Republic.
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Protas L, Sosunov EA, Anyukhovsky EP, Moïse NS, Rosen MR, Robinson RB. Regional dispersion of L-type calcium current in ventricular myocytes of German shepherd dogs with lethal cardiac arrhythmias. Heart Rhythm 2005; 2:172-6. [PMID: 15851292 DOI: 10.1016/j.hrthm.2004.10.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Accepted: 10/26/2004] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The purpose of this study was to determine if regional differences in L-type Ca(2+) current (I(Ca,L)) are altered in a German shepherd model of sudden death. BACKGROUND German shepherd dogs with inherited sudden cardiac death have reduced sympathetic innervation in the anteroseptal left ventricle that may contribute to arrhythmias in afflicted animals compared to control unafflicted animals. Differences in a number of repolarizing K(+) currents have been identified in this model, but I(Ca,L) has not been studied. METHODS We measured action potentials in intact tissue and I(Ca,L) in isolated myocytes from anteroseptal and anterobasal left ventricle. RESULTS Action potential plateau level and I(Ca,L) density were significantly lower in unafflicted anteroseptal than in afflicted anteroseptal, afflicted anterobasal, or unafflicted anterobasal. Isoproterenol increased I(Ca,L) density more in the unafflicted anteroseptal group than in the other groups. CONCLUSIONS Differences in I(Ca,L) between afflicted and control animals, combined with our earlier finding of regional reductions in I(Kr), provide a likely substrate for the occurrence of pause-dependent arrhythmias in afflicted animals and for the T-wave abnormalities characterizing them.
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Affiliation(s)
- Lev Protas
- Department of Pharmacology, Center for Molecular Therapeutics, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA
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Abstract
A potentially important mechanism controlling ion channel expression is homeostatic regulation, which can act to maintain a stable electrophysiological phenotype in cardiac myocytes as well as to provide plasticity in response to genetic, pathological, or pharmacological insults. The capabilities and limitations of the homeostatic regulatory mechanisms that contribute to the control of cardiac ion channel expression are the primary topic of this review.
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Affiliation(s)
- Barbara Rosati
- Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY, USA
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