Abstract:
OBJECTIVES:Myocardial ischemia results in an early phase of arrhythmias that primarily involves reentrant mechanisms. However, the trigger that initiates reentry remains unknown. We studied the initiation of reentry attending the development of electrical heterogeneity during simulated ischemia in isolated canine right ventricular subepicardium. METHODS:Preparations consisted of thin epicardial sheets in which action potentials were recorded at 4 sites with intracellular microelectrodes. Tissues were superfused with a hyperkalemic, hypoxic and acidotic 'ischemic' solution. RESULTS:Simulated ischemia produced a 40-70% abbreviation of the action potential at some epicardial sites but not others, primarily by suppressing development of the action potential plateau (or dome). This typically created a marked dispersion of repolarization within the preparation. Local re-excitation ensued when the action potential dome propagated from sites where it was maintained to sites where it was abolished. This mechanism, termed 'phase 2 reentry', produced an extrasystole which then initiated one or more cycles of circus movement reentry. Tachycardias consisting of repetitive reentry occurred in larger tissues. The window for reentry occurred over a range of stimulation rates that shifted to faster rates as ischemia progressed. The transient outward current blocker, 4-aminopyridine, restored the dome at all sites by reversing the ischemia-induced abbreviation of the action potential. Thus, block of the transient outward current restored electrical homogeneity and abolished all reentrant activity within the epicardial preparations. CONCLUSION:Our results implicate phase 2 reentry as a new mechanism for genesis of extrasystoles during simulated ischemia and identify this mechanism as a trigger of circus movement reentry. Validation of this hypothesis awaits the results of future studies using high-resolution recording techniques.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Lukas A,Antzelevitch Csubject
Has Abstractpub_date
1996-09-01 00:00:00pages
593-603issue
3eissn
0008-6363issn
1755-3245pii
0008636396001150journal_volume
32pub_type
杂志文章abstract:AIMS:Human influenza A virus (hIAV) infection is associated with important cardiovascular complications, although cardiac infection pathophysiology is poorly understood. We aimed to study the ability of hIAV of different pathogenicity to infect the mouse heart, and establish the relationship between the infective capac...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvaa117
更新日期:2020-04-28 00:00:00
abstract:Aims:Sirtuin 3 (Sirt3) is a mitochondrial, nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase that reduces oxidative stress by activation of superoxide dismutase 2 (SOD2). Oxidative stress enhances arterial thrombosis. This study investigated the effects of genetic Sirt3 deletion on arterial thrombosis in m...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvy036
更新日期:2018-07-01 00:00:00
abstract:AIMS:The regulation of vascular diameter by vasoconstrictors and vasodilators requires that vascular smooth muscle cells (VSMCs) be physically coupled to extracellular matrix (ECM) and neighbouring cells in order for a vessel to mechanically function and transfer force. The hypothesis was tested that integrin-mediated ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvs239
更新日期:2012-10-01 00:00:00
abstract:OBJECTIVE:To determine the role of calcineurin and Src tyrosine kinase in the regulation of inducible nitric oxide synthase (iNOS) expression and protection in cardiomyocytes. METHODS:iNOS expression was studied in isolated neonatal rat ventricular myocyte cultures in response to bacterial lipopolysaccharide (LPS) or ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2006.05.026
更新日期:2006-09-01 00:00:00
abstract:AIMS:During restenosis, vascular smooth muscle cells (VSMCs) migrate from the vascular media to the developing neointima. Preventing VSMC migration is therefore a therapeutic target for restenosis. Drugs, such as prostacyclin analogues, that increase the intracellular concentration of cyclic adenosine monophosphate (cA...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvv176
更新日期:2015-09-01 00:00:00
abstract:OBJECTIVE:The aim was to investigate the effect of lowering external potassium on the sensitivity of the normal and hypertrophied rat heart to arrhythmias induced by increases in ventricular wall stress. METHODS:The isolated working heart model was used to compare hypertrophied hearts from the spontaneously hypertensi...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract:STUDY OBJECTIVE:The aim of the study was to determine whether the deleterious effects of anaesthesia on cardiac muscle function were due to disturbance of protein synthesis. Comparative investigations were made on anaerobic and aerobic skeletal muscles, and plasma insulin and growth hormone levels were also measured to...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/25.4.314
更新日期:1991-04-01 00:00:00
abstract:OBJECTIVES:To characterize the 'anti-ischemic' effects of adenosine metabolism inhibition in ischemic-reperfused myocardium. METHODS:Perfused C57/B16 mouse hearts were subjected to 20 min ischemia 40 min reperfusion in the absence or presence of adenosine deaminase inhibition (50 microM erythro-2-(2-hydroxy-3-nonyl)ad...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(01)00360-1
更新日期:2001-10-01 00:00:00
abstract:AIMS:Free fatty acids induce apoptosis in cardiomyocytes, which is implicated in lipotoxic cardiomyopathy. However, the underlying mechanisms remain not fully understood. MicroRNAs (miRNAs) are non-coding small RNAs that control gene expression at the post-transcriptional level. Dysregulated miRNAs have been shown to b...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvr145
更新日期:2011-10-01 00:00:00
abstract::Most of our knowledge about the modulation of platelet function by catecholamines is based on observations of acute in vitro actions. Little is known about the effects of chronically elevated or reduced adrenergic stimulation of the platelets. We therefore treated rats for 8 weeks with either adrenaline or the beta-bl...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/23.2.112
更新日期:1989-02-01 00:00:00
abstract:OBJECTIVE:Dexamethasone-eluting stents are currently under evaluation to prevent post-angioplasty restenosis. The efficacy and safety of dexamethasone as an anti-restenotic agent is still unclear. We assess the effect of perivascular delivery of dexamethasone on vascular pathology in a mouse model of restenosis. METHO...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2005.06.015
更新日期:2005-12-01 00:00:00
abstract:AIMS:Recent immunohistochemical studies observed the loss of plakoglobin (PG) from the intercalated disc (ID) as a hallmark of arrhythmogenic right ventricular cardiomyopathy (ARVC), suggesting a final common pathway for this disease. However, the underlying molecular processes are poorly understood. METHODS AND RESUL...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvq353
更新日期:2011-04-01 00:00:00
abstract:AIMS:Autonomic dysfunction can promote atrial fibrillation (AF) and results from AF-related remodelling. N-type Ca2+-channels (NTCCs) at sympathetic nerve terminals mediate Ca2+-entry that triggers neurotransmitter release. AF-associated remodelling plays an important role in AF pathophysiology but the effects of NTCC ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz136
更新日期:2019-12-01 00:00:00
abstract:OBJECTIVE:Myocardial adaptation has been reported to result from mild but chronic ischaemia in the hearts of patients with coronary artery disease. The aim of this study was to test the hypothesis that the responses of the chronically hypoxic myocardium to an episode of severe ischaemia, or the effects of acute ischaem...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.3.312
更新日期:1994-03-01 00:00:00
abstract::The 'master regulatory factors' that position at the top of the genetic hierarchy of lineage determination have been a focus of intense interest, and have been investigated in various systems. Etv2/Etsrp71/ER71 is such a factor that is both necessary and sufficient for the development of haematopoietic and endothelial...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvx133
更新日期:2017-09-01 00:00:00
abstract::Angiotensin II has been implicated as an important factor in cardiac remodeling, particularly in the development of pathological left ventricular hypertrophy. It is generally assumed that angiotensin II is able to alter the phenotype of cardiac myocytes and fibroblasts, and several experiments have suggested that this...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(01)00448-5
更新日期:2002-02-01 00:00:00
abstract:AIMS:Shock wave therapy (SWT) represents a clinically widely used angiogenic and thus regenerative approach for the treatment of ischaemic heart or limb disease. Despite promising results in preclinical and clinical trials, the exact mechanism of action remains unknown. Toll-like receptor 3, which is part of the innate...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvv272
更新日期:2016-02-01 00:00:00
abstract:OBJECTIVE:A circadian rhythm of blood pressure has been demonstrated both in subjects who are physically active during the day and in those confined to bed. The study of the circadian rhythm of arterial flow and peripheral resistance, on the other hand, is limited to pioneer experiments. This paper is aimed at demonstr...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00237-5
更新日期:1999-01-01 00:00:00
abstract:OBJECTIVES:Prior studies have shown that the performance of the left ventricle on any one beat is influenced by the mechanical events of the previous beat, a phenomenon called "previous-beat contraction history". This previous-beat contraction history, which appears to be an interplay between the mechanical events of o...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1996-07-01 00:00:00
abstract:BACKGROUND:A recent genome-wide association study identified a susceptibility locus for atrial fibrillation at the KCNN3 gene. Since the KCNN3 gene encodes for a small conductance calcium-activated potassium channel, we hypothesized that overexpression of the SK3 channel increases susceptibility to cardiac arrhythmias....
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvt269
更新日期:2014-02-01 00:00:00
abstract:STUDY OBJECTIVE:The aim was to evaluate the thrombolytic efficacy of recombinant double chain tissue plasminogen activator (Duteplase, t-PA) given as a single intravenous bolus versus an infusion in a canine model of coronary arterial occlusion/reperfusion. DESIGN:Coronary arterial thrombi were induced by a copper coi...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/25.3.184
更新日期:1991-03-01 00:00:00
abstract:OBJECTIVE:The aim was to compare differences in peak twitch force occurring despite similar degrees of right ventricular hypertrophy in ferrets with pulmonary artery banding at either weanling or juvenile age. METHODS:After inducing pressure overload hypertrophy by banding the pulmonary artery of weanling and juvenile...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract::Numerous epidemiological studies documented an inverse relationship between plasma high-density lipoprotein (HDL) cholesterol levels and the extent of atherosclerotic disease. However, clinical interventions targeting HDL cholesterol failed to show clinical benefits with respect to cardiovascular risk reduction, sugge...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvu136
更新日期:2014-08-01 00:00:00
abstract::Primary cardiomyopathy is an important cause of mortality in children and adults. Apart from inherited disorders of myocardial contractile and structural proteins, several defects of energy metabolism may cause cardiomyopathy. Most of the energy required for myocardial contraction is derived from aerobic metabolism. F...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(97)00141-7
更新日期:1997-08-01 00:00:00
abstract:OBJECTIVES:The purpose of this study was to investigate the changes in beta-adrenoceptor density (Bmax) and distribution in a model of chronic myocardial infarction in rats, and to relate possible changes to hemodynamic and neurohumoral abnormalities. In addition, we examined the effects of 8 weeks treatment with ibopa...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::The acute haemodynamic effects of taurine were studied in normal and in beta blocker (propranolol) or calcium antagonist (diltiazem) treated rabbits and in rabbits with experimentally produced chronic aortic regurgitation. The administration of taurine (25 mg.kg-1) did not affect heart rate and left ventricular end di...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/21.4.241
更新日期:1987-04-01 00:00:00
abstract:OBJECTIVE:The aim was to study the effect of thyroid hormone on collagen gene expression in the myocardium of the tight skin mouse (TSK), a genetic model of myocardial fibrosis. METHODS:Heterozygous male (TSK/+) (n = 20) and normal (+/+) homozygous mice (n = 20), 1.5-2 months old of the C57 BL/6 strain were studied. V...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/26.6.603
更新日期:1992-06-01 00:00:00
abstract:OBJECTIVES:We measured the uptake of technetium-99m tetrofosmin (99m Tc) and thallium-201 (201 TI) in areas of healed transmural myocardial infarction and in the regions of acute peri-infarction ischemia. METHODS:Anesthetised pigs with a 1-month old transmural infarction elicited by permanent ligature of the left ante...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(97)00316-7
更新日期:1998-04-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to examine the effect of ischaemia on vascular responses to endothelium-dependent and endothelium-independent vasodilators and on vasoconstrictor responses. Furthermore, the ability of preconditioning to prevent ischaemia-induced changes in vascular reactivity was examined in the rat...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(96)00167-8
更新日期:1996-12-01 00:00:00
abstract:OBJECTIVE:Evidence suggests important relationships among chronic inflammatory processes, endothelial dysfunction, hypertension and target organ damage. The present study examined the effects of chronic treatment with an anti-inflammatory p38 mitogen-activated protein kinase (MAPK) inhibitor (SB-239063AN) in the N(omeg...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2004.12.021
更新日期:2005-04-01 00:00:00