1
|
Wang Q, Yuan J, Shen H, Zhu Q, Chen B, Wang J, Zhu W, Yorek MA, Hall DD, Wang Z, Song LS. Calpain inhibition protects against atrial fibrillation by mitigating diabetes-associated atrial fibrosis and calcium handling dysfunction in type 2 diabetes mice. Heart Rhythm 2024; 21:1143-1151. [PMID: 38395244 DOI: 10.1016/j.hrthm.2024.02.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/13/2024] [Accepted: 02/15/2024] [Indexed: 02/25/2024]
Abstract
BACKGROUND Diabetes mellitus (DM) is a major risk factor for atrial structural remodeling and atrial fibrillation (AF). Calpain activity is hypothesized to promote atrial remodeling and AF. OBJECTIVE The purpose of this study was to investigate the role of calpain in diabetes-associated AF, fibrosis, and calcium handling dysfunction. METHODS DM-associated AF was induced in wild-type (WT) mice and in mice overexpressing the calpain inhibitor calpastatin (CAST-OE) using high-fat diet feeding followed by low-dose streptozotocin injection (75 mg/kg). DM and AF outcomes were assessed by measuring blood glucose levels, fibrosis, and AF susceptibility during transesophageal atrial pacing. Intracellular Ca2+ transients, spontaneous Ca2+ release events, and intracellular T-tubule membranes were measured by in situ confocal microscopy. RESULTS WT mice with DM had significant hyperglycemia, atrial fibrosis, and AF susceptibility with increased atrial myocyte calpain activity and Ca2+ handling dysfunction relative to control treated animals. CAST-OE mice with DM had a similar level of hyperglycemia as diabetic WT littermates but lacked significant atrial fibrosis and AF susceptibility. DM-induced atrial calpain activity and downregulation of the calpain substrate junctophilin-2 were prevented by CAST-OE. Atrial myocytes of diabetic CAST-OE mice exhibited improved T-tubule membrane organization, Ca2+ handling, and reduced spontaneous Ca2+ release events compared to littermate controls. CONCLUSION This study confirmed that DM promotes calpain activation, atrial fibrosis, and AF in mice. CAST-OE effectively inhibits DM-induced calpain activation and reduces atrial remodeling and AF incidence through improved intracellular Ca2+ homeostasis. Our results support calpain inhibition as a potential therapy for preventing and treating AF in DM patients.
Collapse
Affiliation(s)
- Qing Wang
- Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; The Collaborative Innovation Center, Jining Medical University, Jining, Shandong, China; Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Jinxiang Yuan
- The Collaborative Innovation Center, Jining Medical University, Jining, Shandong, China; Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Hua Shen
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Cardiovascular Surgery, Chinese PLA General Hospital, Beijing, China
| | - Qi Zhu
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Biyi Chen
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Jinxi Wang
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Weizhong Zhu
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Mark A Yorek
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Veterans Affairs Iowa City Health Care System, Iowa City, Iowa; Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Duane D Hall
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Zhinong Wang
- Department of Cardiothoracic Surgery, Changzheng Hospital, Naval Medical University, Shanghai, China.
| | - Long-Sheng Song
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Veterans Affairs Iowa City Health Care System, Iowa City, Iowa; Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa.
| |
Collapse
|
2
|
van der Does WFB, Houck CA, Heida A, van Schie MS, van Schaagen FRN, Taverne YJHJ, Bogers AJJC, de Groot NMS. Atrial electrophysiological characteristics of aging. J Cardiovasc Electrophysiol 2021; 32:903-912. [PMID: 33650738 PMCID: PMC8048566 DOI: 10.1111/jce.14978] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/18/2021] [Accepted: 01/27/2021] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Advancing age is a known risk factor for developing atrial fibrillation (AF), yet it is unknown which electrophysiological changes contribute to this increased susceptibility. The goal of this study is to investigate conduction disturbances and unipolar voltages (UV) related to aging. METHODS We included 216 patients (182 male, age: 36-83 years) without a history of AF undergoing elective coronary artery bypass surgery. Five seconds of sinus rhythm were recorded intraoperatively at the right atrium (RA), Bachmann's bundle (BB), the left atrium and the pulmonary vein area (PVA). Conduction delay (CD), -block (CB), -velocity (CV), length of longest CB lines and UV were assessed in all regions. RESULTS With aging, increasing conduction disturbances were found, particularly at RA and BB (RA: longest CB line rs = .158, p = .021; BB: CB prevalence rs = .206, p = .003; CV rs = -.239, p < .0005). Prevalence of low UV areas (UV <5th percentile) increased with aging at the BB and PVA (BB: rs = .237, p < .0005 and PVA: rs = .228, p = .001). CONCLUSIONS Aging is accompanied by an increase in conduction disturbances during sinus rhythm and a higher prevalence of low UV areas, particularly at BB and in the RA. These electrophysiological alterations could in part explain the increasing susceptibility to AF development associated with aging.
Collapse
Affiliation(s)
- Willemijn F B van der Does
- Unit Translational Electrophysiology, Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Charlotte A Houck
- Unit Translational Electrophysiology, Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Cardiothoracic surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Annejet Heida
- Unit Translational Electrophysiology, Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Mathijs S van Schie
- Unit Translational Electrophysiology, Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Frank R N van Schaagen
- Department of Cardiothoracic surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Yannick J H J Taverne
- Department of Cardiothoracic surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ad J J C Bogers
- Department of Cardiothoracic surgery, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Natasja M S de Groot
- Unit Translational Electrophysiology, Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| |
Collapse
|
3
|
Nesterova T, Shmarko D, Ushenin K, Solovyova O. In-silico analysis of aging mechanisms of action potential remodeling in human atrial cardiomyocites. BIO WEB OF CONFERENCES 2020. [DOI: 10.1051/bioconf/20202201025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Electrophysiology of cardiomyocytes changes with aging. Agerelated ionic remodeling in cardiomyocytes may increase the incidence and prevalence of atrial fibrillation (AF) in the elderly and affect the efficiency of antiarrhythmic drugs. There is the deep lack of experimental data on an action potential and transmembrane currents recorded in the healthy human cardiomyocytes of different age. Experimental data in mammals is also incomplete and often contradicting depending on the experimental conditions. In this in-silico study, we used a population of ionic models of human atrial cardiomyocytes to transfer data on the age- related ionic remodeling in atrial cardiomyocytes from canines and mice to predict possible consequences for human cardiomyocyte activity. Based on experimental data, we analyzes two hypotheses on the aging effect on the ionic currents using two age-related sets of varied model parameters and evaluated corresponding changes in action potential morphology with aging. Using the two populations of aging models, we analyzed the agedependent sensitivity of atrial cardiomyocytes to Dofetilide which is one of the antiarrhythmic drugs widely used in patients with atrial fibrillation.
Collapse
|
4
|
Zhang G, Abuduoufu A, Zhou X, Li Y, Zhang L, Lu Y, Zhang J, Xin Q, Tang BP. Monocyte Chemoattractant Protein-1-Induced Protein in Age-Related Atrial Fibrillation and Its Association with Circulating Fibrosis Biomarkers. Cardiology 2019; 142:244-249. [PMID: 31203274 DOI: 10.1159/000499932] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 03/25/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND Atrial fibrillation (AF), for which age is an independent risk factor, is the most common persistent arrhythmia. Monocyte chemoattractant protein-1-induced protein (MCPIP), a transcription factor that induces a series of inflammation and cell death procedures, has been indicated to cause cardiomyocyte death in ischemic cardiomyopathy. The objective of this research was to investigate the relationship between age-related AF and MCPIP. METHODS A total of 1,084 participants were included in this study, including 542 AF patients and 542 non-AF controls. Their medical histories were collected and analyzed. Moreover, blood samples were collected, and ELISA tests for expression of the inflammatory factor MCPIP and the fibrosis biomarkers pro-collagen type III N-terminal peptide (PIIINP) and type I collagen C-terminal telopeptide (ICTP) were conducted. Finally, a correlation analysis of these inflammatory factors and biomarkers was performed based on the ELISA results. RESULTS We compared the echocardiography results of AF patients and found that the left ventricular ejection fraction and left atrial appendage velocity decreased with age (p < 0.05). Moreover, ELISA analysis of these samples showed that the expression of MCPIP was the highest in elderly patients with AF (p < 0.05), and there was no significant difference in expression between adult AF patients and elderly controls (p > 0.05). Finally, the correlation analysis demonstrated that the expressions of MCPIP, PIIINP, and ICTP were positively correlated in the elderly AF patient group, the adult AF group, and the elderly control group (p < 0.05). CONCLUSION MCPIP expression was higher in age-related AF than in the other patient groups and it was associated with AF-induced fibrosis.
Collapse
Affiliation(s)
- Gege Zhang
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Asiyanmu Abuduoufu
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Xianhui Zhou
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Yaodong Li
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Ling Zhang
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Yanmai Lu
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Jianghua Zhang
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Qiang Xin
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China
| | - Bao-Peng Tang
- Department of Cardiology, First Affiliated Hospital, Xinjiang Medical University, Urumqi, China,
| |
Collapse
|
5
|
Hamilton S, Terentyev D. Altered Intracellular Calcium Homeostasis and Arrhythmogenesis in the Aged Heart. Int J Mol Sci 2019; 20:ijms20102386. [PMID: 31091723 PMCID: PMC6566636 DOI: 10.3390/ijms20102386] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 04/29/2019] [Accepted: 05/08/2019] [Indexed: 12/17/2022] Open
Abstract
Aging of the heart is associated with a blunted response to sympathetic stimulation, reduced contractility, and increased propensity for arrhythmias, with the risk of sudden cardiac death significantly increased in the elderly population. The altered cardiac structural and functional phenotype, as well as age-associated prevalent comorbidities including hypertension and atherosclerosis, predispose the heart to atrial fibrillation, heart failure, and ventricular tachyarrhythmias. At the cellular level, perturbations in mitochondrial function, excitation-contraction coupling, and calcium homeostasis contribute to this electrical and contractile dysfunction. Major determinants of cardiac contractility are the intracellular release of Ca2+ from the sarcoplasmic reticulum by the ryanodine receptors (RyR2), and the following sequestration of Ca2+ by the sarco/endoplasmic Ca2+-ATPase (SERCa2a). Activity of RyR2 and SERCa2a in myocytes is not only dependent on expression levels and interacting accessory proteins, but on fine-tuned regulation via post-translational modifications. In this paper, we review how aberrant changes in intracellular Ca2+ cycling via these proteins contributes to arrhythmogenesis in the aged heart.
Collapse
Affiliation(s)
- Shanna Hamilton
- Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
| | - Dmitry Terentyev
- Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
| |
Collapse
|
6
|
Cui C, Geng L, Shi J, Zhu Y, Yang G, Wang Z, Wang J, Chen M. Structural and electrophysiological dysfunctions due to increased endoplasmic reticulum stress in a long-term pacing model using human induced pluripotent stem cell-derived ventricular cardiomyocytes. Stem Cell Res Ther 2017; 8:109. [PMID: 28490375 PMCID: PMC5426064 DOI: 10.1186/s13287-017-0566-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/16/2017] [Accepted: 04/26/2017] [Indexed: 01/15/2023] Open
Abstract
Background Long-term ventricular pacing has deleterious effects and becomes more significant when cumulative percent ventricular pacing (Cum%VP) exceeds 40% of time. However, cellular disturbances and pathways by which pacing leads to myocardial disorders are not well understood. Attempts to resolve these questions have been hampered by difficulties in obtaining human cardiac tissue and the inability to build a longer-lasting (lasting longer than weeks) pacing model in vitro. Methods Human induced pluripotent stem cell-derived ventricular cardiomyocytes (VCMs) were cultured in the presence of electrical stimulation for 2 weeks. Quantitative structural and electrophysiological analyses were used to define the functional disturbances of pacing. Results Compared to controls, paced VCMs exhibited a remarkable reduction in the contractile protein expression, an increased apoptosis ratio and electrophysiological remodelling in a Cum%VP-dependent manner. Investigation of the protein expression levels revealed that long-term pacing universally activated both ER stress and downstream calpain. Moreover, the inhibition of calpain attenuated the adverse effects on the structural remodelling and increased the ICa, L in paced VCMs. Conclusions The results demonstrated that pacing VCMs for 2 weeks in vitro led to a series of structural and electrophysiological dysfunctions. The increased ER stress and downstream calpain could be a central mechanism underlying the disease pathogenesis. This finding could represent a new therapeutic target in the management of long-term pacing patients. Electronic supplementary material The online version of this article (doi:10.1186/s13287-017-0566-6) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Chang Cui
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Le Geng
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Jiaojiao Shi
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Yue Zhu
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Gang Yang
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Zidun Wang
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Jiaxian Wang
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Minglong Chen
- Division of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.
| |
Collapse
|
7
|
Wang W, Zhu Y, Yi J, Cheng W. Nkx2.5/CARP signaling pathway contributes to the regulation of ion channel remodeling induced by rapid pacing in rat atrial myocytes. Mol Med Rep 2016; 14:3848-54. [PMID: 27600472 DOI: 10.3892/mmr.2016.5727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 07/18/2016] [Indexed: 11/06/2022] Open
Abstract
Remodeling of atrial electrophysiology and structure is the primary feature of atrial fibrillation (AF). Evidence suggests that abnormalities in the expression levels of embryological cardiovascular development‑associated transcription factors, including Nkx2.5, are crucial for the development of AF. Rat atrial myocardial cells (AMCs) in culture dishes were placed in an electric field and stimulated. Transmission electron microscopy was used to observe the ultrastucture prior to and following rapid pacing. The action potential durations and effective refractory periods were measured. RT‑PCR and western blotting were performed to investigate the effect of rapid pacing on the expression levels of ion channel and nuclear proteins in AMCs. Nkx2.5 short interfering RNA (siRNA) transfection was performed. Through this in vitro rat AMC culture and rapid pacing model, it was demonstrated that rapid pacing shortened the action potential and downregulated the expression levels of L‑type calcium and potassium channels. Expression levels of Nkx2.5 and cardiac ankyrin repeat protein (CARP) were significantly upregulated by rapid pacing at the mRNA and protein levels. siRNA‑mediated Nkx2.5 silencing attenuated the rapid pacing‑induced downreglation of ion channel levels. These results suggest that the Nkx2.5/CARP signaling pathway contributes to the early electrical remodeling process of AF.
Collapse
Affiliation(s)
- Wei Wang
- Department of Cardiovascular Surgery, The Second Affiliated Hospital of Third Military Medical University, Chongqing 400038, P.R. China
| | - Yun Zhu
- Department of Cardiovascular Surgery, The Second Affiliated Hospital of Third Military Medical University, Chongqing 400038, P.R. China
| | - Jianguang Yi
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Third Military Medical University, Chongqing 400038, P.R. China
| | - Wei Cheng
- Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Third Military Medical University, Chongqing 400038, P.R. China
| |
Collapse
|
8
|
Nakayama H, Nishida K, Otsu K. Macromolecular Degradation Systems and Cardiovascular Aging. Circ Res 2016; 118:1577-92. [DOI: 10.1161/circresaha.115.307495] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 02/29/2016] [Indexed: 11/16/2022]
Abstract
Aging-related cardiovascular diseases are a rapidly increasing problem worldwide. Cardiac aging demonstrates progressive decline of diastolic dysfunction of ventricle and increase in ventricular and arterial stiffness accompanied by increased fibrosis stimulated by angiotensin II and proinflammatory cytokines. Reactive oxygen species and multiple signaling pathways on cellular senescence play major roles in the process. Aging is also associated with an alteration in steady state of macromolecular dynamics including a dysfunction of protein synthesis and degradation. Currently, impaired macromolecular degradation is considered to be closely related to enhanced inflammation and be involved in the process and mechanism of cardiac aging. Herein, we review the role and mechanisms of the degradation system of intracellular macromolecules in the process and pathophysiology of cardiovascular aging.
Collapse
Affiliation(s)
- Hiroyuki Nakayama
- From the Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (H.N.); and Cardiovascular Division, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom (K.N., K.O.)
| | - Kazuhiko Nishida
- From the Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (H.N.); and Cardiovascular Division, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom (K.N., K.O.)
| | - Kinya Otsu
- From the Laboratory of Clinical Science and Biomedicine, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan (H.N.); and Cardiovascular Division, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom (K.N., K.O.)
| |
Collapse
|
9
|
Voigt N, Pearman CM, Dobrev D, Dibb KM. Methods for isolating atrial cells from large mammals and humans. J Mol Cell Cardiol 2015; 86:187-98. [PMID: 26186893 DOI: 10.1016/j.yjmcc.2015.07.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/07/2015] [Accepted: 07/09/2015] [Indexed: 01/04/2023]
Abstract
The identification of disturbances in the cellular structure, electrophysiology and calcium handling of atrial cardiomyocytes is crucial to the understanding of common pathologies such as atrial fibrillation. Human right atrial specimens can be obtained during routine cardiac surgery and may be used for isolation of atrial myocytes. These samples provide the unique opportunity to directly investigate the effects of human disease on atrial myocytes. However, atrial myocytes vary greatly between patients, there is little if any access to truly healthy controls and the challenges associated with assessing the in vivo effects of drugs or devices in man are considerable. These issues highlight the need for animal models. Large mammalian models are particularly suitable for this purpose as their cardiac structure and electrophysiology are comparable with humans. Here, we review techniques for obtaining atrial cardiomyocytes. We start with background information on solution composition. Agents shown to increase viable cell yield will then be explored followed by a discussion of the use of tissue-dissociating enzymes. Protocols are detailed for the perfusion method of cell isolation in large mammals and the chunk digest methods of cell isolation in humans.
Collapse
Affiliation(s)
- Niels Voigt
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany.
| | - Charles M Pearman
- Unit of Cardiac Physiology, Institute of Cardiovascular Sciences, 3.26 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, United Kingdom.
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany.
| | - Katharine M Dibb
- Unit of Cardiac Physiology, Institute of Cardiovascular Sciences, 3.26 Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, United Kingdom.
| |
Collapse
|