1
|
Kuzmin V, Ushenin KS, Dzhumaniiazova IV, Abramochkin D, Vornanen M. High temperature and hyperkalemia cause exit block of action potentials at the atrioventricular junction of rainbow trout (Oncorhynchus mykiss) heart. J Therm Biol 2022; 110:103378. [PMID: 36462845 DOI: 10.1016/j.jtherbio.2022.103378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 10/13/2022] [Accepted: 10/21/2022] [Indexed: 11/07/2022]
Abstract
At critically high temperatures, atrioventricular (AV) block causes ventricular bradycardia and collapse of cardiac output in fish. Here, the possible role of the AV canal in high temperature-induced heart failure was examined. To this end, optical mapping was used to measure action potential (AP) conduction in isolated AV junction preparations of the rainbow trout (Oncorhynchus mykiss) heart during acute warming/cooling in the presence of 4 or 8 mM external K+ concentration. The preparation included the AV canal and some atrial and ventricular tissue at its edges, and it was paced either from atrial or ventricular side at a frequency of 0.67 Hz (40 beats min-1) to trigger forward (anterograde) and backward (retrograde) conduction, respectively. The propagation of AP was fast in atrial and ventricular tissues, but much slower in the AV canal, causing an AV delay. Acute warming from 15 °C to 27 °C or cooling from 15 °C to 5 °C did not impair AP conduction in the AV canal, as both anterograde and retrograde excitations propagated regularly through the AV canal. In contrast, anterograde conduction through the AV canal did not trigger ventricular excitation at the boundary zone between the AV canal and the ventricle when extracellular K+ concentration was raised from 4 mM to 8 mM at 27 °C. Also, the retrograde conduction was blocked at the border between the AV canal and the atrium in high K+ at 27 °C. These findings suggest that the AV canal is resistant against high temperatures (and high K+), but the ventricular muscle cannot be excited by APs coming from the AV canal when temperature and external K+ concentration are simultaneously elevated. Therefore, bradycardia at high temperatures in fish may occur due to inability of AP of the AV canal to trigger ventricular AP at the junctional zone between the AV canal and the proximal part of the ventricle.
Collapse
Affiliation(s)
- Vladislav Kuzmin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye gory, building 12, Moscow, 119991, Russia.
| | - Konstantin S Ushenin
- Ural Federal University, Institute of Natural Sciences and Mathematics, Ekaterinburg, Kuybysheva Str., 48, Ekaterinburg, 620026, Russia
| | - Irina V Dzhumaniiazova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye gory, building 12, Moscow, 119991, Russia
| | - Denis Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye gory, building 12, Moscow, 119991, Russia; Laboratory of Cardiac Electrophysiology, National Medical Research Center for Cardiology, Moscow, Russia; Department of Physiology, Pirogov Russian National Research Medical University, Ostrovitjanova 1, Moscow, 117997, Russia
| | - Matti Vornanen
- University of Eastern Finland, Department of Environmental and Biological Sciences, P.O.Box 111, 80101, Joensuu, Finland
| |
Collapse
|
2
|
Pustovit KB, Samoilova DV, Abramochkin DV, Filatova TS, Kuzmin VS. α1-adrenergic receptors accompanied by GATA4 expression are related to proarrhythmic conduction and automaticity in rat interatrial septum. J Physiol Biochem 2022; 78:793-805. [PMID: 35802254 DOI: 10.1007/s13105-022-00902-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 05/19/2022] [Indexed: 11/25/2022]
Abstract
The development of interatrial septum (IAS) is a complicated process, which continues during postnatal life. The hypertrophic signals in developing heart are mediated among others by α-adrenergic pathways. These facts suggest the presence of specific electrophysiological features in developing IAS. This study was aimed to investigate the electrical activity in the tissue preparations of IAS from rat heart in normal conditions and under stimulation of adrenoreceptors. Intracellular recording of electrical activity revealed less negative level of resting membrane potential in IAS if compared to myocardium of left atrium. In normal conditions, non-paced IAS preparations were quiescent, but noradrenaline (10-5 M) and phenylephrine (10-5 M) induced spontaneous action potentials, which could be abolished by α1-blocker prazosin (10-5 M), but not β1-blocker atenolol (10-5 M). Optical mapping showed drastic phenylephrine-induced slowing of conduction in adult rat IAS. The α1-dependent ectopic automaticity of IAS myocardium might be explained by immunohistochemical data indicating the presence of transcription factor GATA4 and abundant α1A-adrenoreceptors in myocytes from adult rat IAS. An elevated sensitivity to adrenergic stimulation due to involvement of α1-adrenergic pathways may underlie increased proarrhythmic potential of adult IAS at least in rats.
Collapse
Affiliation(s)
- Ksenia B Pustovit
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Daria V Samoilova
- N. N. Blokhin National Medical Research Centre of Oncology, Kashirskoye sh., 24, Moscow, Russia
| | - Denis V Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.
| | - Tatiana S Filatova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.,Laboratory of Cardiac Electrophysiology, National Medical Research Center for Cardiology, 3rd Cherepkovskaya, 15a, Moscow, Russia.,Department of Physiology, Pirogov Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia
| | - Vladislav S Kuzmin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| |
Collapse
|
3
|
Steimle JD, Grisanti Canozo FJ, Park M, Kadow ZA, Samee MAH, Martin JF. Decoding the PITX2-controlled genetic network in atrial fibrillation. JCI Insight 2022; 7:e158895. [PMID: 35471998 PMCID: PMC9221021 DOI: 10.1172/jci.insight.158895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Atrial fibrillation (AF), the most common sustained cardiac arrhythmia and a major risk factor for stroke, often arises through ectopic electrical impulses derived from the pulmonary veins (PVs). Sequence variants in enhancers controlling expression of the transcription factor PITX2, which is expressed in the cardiomyocytes (CMs) of the PV and left atrium (LA), have been implicated in AF predisposition. Single nuclei multiomic profiling of RNA and analysis of chromatin accessibility combined with spectral clustering uncovered distinct PV- and LA-enriched CM cell states. Pitx2-mutant PV and LA CMs exhibited gene expression changes consistent with cardiac dysfunction through cell type-distinct, PITX2-directed, cis-regulatory grammars controlling target gene expression. The perturbed network targets in each CM were enriched in distinct human AF predisposition genes, suggesting combinatorial risk for AF genesis. Our data further reveal that PV and LA Pitx2-mutant CMs signal to endothelial and endocardial cells through BMP10 signaling with pathogenic potential. This work provides a multiomic framework for interrogating the basis of AF predisposition in the PVs of humans.
Collapse
Affiliation(s)
| | | | | | - Zachary A. Kadow
- Program in Developmental Biology, and
- Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas, USA
| | | | - James F. Martin
- Department of Integrative Physiology
- Texas Heart Institute, Houston, Texas, USA
- Center for Organ Repair and Renewal, Baylor College of Medicine, Houston, Texas, USA
| |
Collapse
|
4
|
Kuzmin VS, Malykhina IA, Pustovit KB, Ivanova AD, Kuniewicz M, Walocha J, Atkinson A, Aminu AJ, Dobrzynski H. Inflammatory degranulation of the cardiac resident mast cells suppresses the pacemaking and affects activation pattern in the sinoatrial node. TRANSLATIONAL RESEARCH IN ANATOMY 2022. [DOI: 10.1016/j.tria.2022.100170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|
5
|
Automatic Activity Arising in Cardiac Muscle Sleeves of the Pulmonary Vein. Biomolecules 2021; 12:biom12010023. [PMID: 35053171 PMCID: PMC8773798 DOI: 10.3390/biom12010023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 02/06/2023] Open
Abstract
Ectopic activity in the pulmonary vein cardiac muscle sleeves can both induce and maintain human atrial fibrillation. A central issue in any study of the pulmonary veins is their difference from the left atrial cardiac muscle. Here, we attempt to summarize the physiological phenomena underlying the occurrence of ectopic electrical activity in animal pulmonary veins. We emphasize that the activation of multiple signaling pathways influencing not only myocyte electrophysiology but also the means of excitation–contraction coupling may be required for the initiation of triggered or automatic activity. We also gather information regarding not only the large-scale structure of cardiac muscle sleeves but also recent studies suggesting that cellular heterogeneity may contribute to the generation of arrythmogenic phenomena and to the distinction between pulmonary vein and left atrial heart muscle.
Collapse
|
6
|
Ivanova AD, Filatova TS, Abramochkin DV, Atkinson A, Dobrzynski H, Kokaeva ZG, Merzlyak EM, Pustovit KB, Kuzmin VS. Attenuation of inward rectifier potassium current contributes to the α1-adrenergic receptor-induced proarrhythmicity in the caval vein myocardium. Acta Physiol (Oxf) 2021; 231:e13597. [PMID: 33306261 DOI: 10.1111/apha.13597] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 11/19/2020] [Accepted: 12/07/2020] [Indexed: 12/31/2022]
Abstract
AIM This study is aimed at investigation of electrophysiological effects of α1-adrenoreceptor (α1-AR) stimulation in the rat superior vena cava (SVC) myocardium, which is one of the sources of proarrhythmic activity. METHODS α1-ARs agonists (phenylephrine-PHE or norepinephrine in presence of atenolol-NE + ATL) were applied to SVC and atrial tissue preparations or isolated cardiomyocytes, which were examined using optical mapping, glass microelectrodes or whole-cell patch clamp. α1-ARs distribution was evaluated using immunofluorescence. Kir2.X mRNA and protein level were estimated using RT-PCR and Western blotting. RESULTS PHE or NE + ATL application caused a significant suppression of the conduction velocity (CV) of excitation and inexcitability in SVC, an increase in the duration of electrically evoked action potentials (APs), a decrease in the maximum upstroke velocity (dV/dtmax ) and depolarization of the resting membrane potential (RMP) in SVC to a greater extent than in atria. The effects induced by α1-ARs activation in SVC were attenuated by protein kinase C inhibition (PKC). The whole-cell patch clamp revealed PHE-induced suppression of outward component of IK1 inward rectifier current in isolated SVC, but not atrial myocytes. These effects can be mediated by α1A subtype of α-ARs found in abundance in rat SVC. The basal IK1 level in SVC was much lower than in atria as a result of the weaker expression of Kir2.2 channels. CONCLUSION Therefore, the reduced density of IK1 in rat SVC cardiomyocytes and sensitivity of this current to α1A-AR stimulation via PKC-dependent pathways might lead to proarrhythmic conduction in SVC myocardium by inducing RMP depolarization, AP prolongation, CV and dV/dtmax decrease.
Collapse
Affiliation(s)
- Alexandra D. Ivanova
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Tatiana S. Filatova
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
| | - Denis V. Abramochkin
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
- Laboratory of Cardiac Electrophysiology National Medical Research Center for Cardiology Moscow Russia
| | - Andrew Atkinson
- Faculty of Biology, Medicine and Health University of Manchester Manchester UK
| | - Halina Dobrzynski
- Faculty of Biology, Medicine and Health University of Manchester Manchester UK
- Heart Embryology and Anatomy Research Team Department of Anatomy Jagiellonian University Medical College Cracow Poland
| | - Zarema G. Kokaeva
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Ekaterina M. Merzlyak
- Shemiakin‐Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Science Moscow Russia
| | - Ksenia B. Pustovit
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
| | - Vladislav S. Kuzmin
- Department of Human and Animal Physiology Lomonosov Moscow State University Moscow Russia
- Department of Physiology Pirogov Russian National Research Medical University Moscow Russia
| |
Collapse
|
7
|
Kuzmin VS, Potekhina VM, Odnoshivkina YG, Chelombitko MA, Fedorov AV, Averina OA, Borodkov AS, Shevtsova AA, Lovat ML, Petrov AM. Proarrhythmic atrial ectopy associated with heart sympathetic innervation dysfunctions is specific for murine B6CBAF1 hybrid strain. Life Sci 2020; 266:118887. [PMID: 33316264 DOI: 10.1016/j.lfs.2020.118887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/25/2020] [Accepted: 12/04/2020] [Indexed: 11/20/2022]
Abstract
A lot of animal models are developed with aim to advance in atrial fibrillation (AF) understanding. The hybrid B6CBAF1 mice are used extensively as a background to create manifestation of various diseases, however, their atrial electrophysiology, autonomic sympathetic innervation of the heart and potential for AF investigation is poorly characterized. In the present study we used ECG and microelectrode recordings from multicellular atrial preparations to reveal attributes of atrial electrical activity in B6CBAF1. Also, experiments with a fluorescent false monoamine neurotransmitter and glyoxylic acid-based staining were carried out to characterize functionally and morphologically catecholaminergic innervation of the B6CBAF1 atria. Atrial myocardium of B6CBAF1 is highly prone to ectopic automaticity and exhibits abnormal spontaneous action potential accompanied by multiple postdepolarizations that result in proarrhythmic triggered activity unlike two parental C57Bl/6 and CBA strains. In vivo experiments revealed that B6CBAF1 hybrids are more susceptible to the norepinephrine induced AF. Also, sympathetic nerve terminals are partially dysfunctional in B6CBAF1 revealing lower ability to accumulate and release neurotransmitters unlike two parental strains. The analysis of the heart rate variability revealed suppressed sympathetic component of the autonomic heart control in B6CBAF1. The organization of sympathetic innervation is very similar morphologically in all three murine strains however the abundance of non-bifurcated catecholamine-positive fibers in B6CBAF1 was increased. These results suggest that B6CBAF1 mice exhibit enhanced intrinsic atrial proarrhythmicity, while the abnormalities of sympathetic neurotransmitter cycling probably underlie disturbed autonomic heart control.
Collapse
Affiliation(s)
- Vlad S Kuzmin
- Lomonosov Moscow State University, Biological Faculty, Department of Human and Animal Physiology, Leninskie gory 1, building 12, 119991 Moscow, Russia; Pirogov Russian National Research Medical University (RNRMU), Ostrovitjanova 1, 117997 Moscow, Russia
| | - Viktoriia M Potekhina
- Lomonosov Moscow State University, Biological Faculty, Department of Human and Animal Physiology, Leninskie gory 1, building 12, 119991 Moscow, Russia.
| | | | - Maria A Chelombitko
- The A.N. Belozersky Institute of Physico-Chemical Biology, MSU, Moscow, Russia
| | - Artem V Fedorov
- Lomonosov Moscow State University, Biological Faculty, Department of Human and Animal Physiology, Leninskie gory 1, building 12, 119991 Moscow, Russia
| | - Olga A Averina
- The A.N. Belozersky Institute of Physico-Chemical Biology, MSU, Moscow, Russia; Institute of Functional Genomics, Lomonosov Moscow State University, Moscow, Russia
| | - Alexey S Borodkov
- Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academу of Sciences, Moscow, Russia
| | - Anna A Shevtsova
- Lomonosov Moscow State University, Faculty of Biology, Department of Genetics, Moscow, Russia
| | - Maxim L Lovat
- Lomonosov Moscow State University, Biological Faculty, Department of Human and Animal Physiology, Leninskie gory 1, building 12, 119991 Moscow, Russia
| | - Alexey M Petrov
- Institute of Neuroscience, Kazan State Medial University, Kazan, Russia; Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", Kazan, Russia
| |
Collapse
|