Abstract:
STUDY OBJECTIVE:It has been suggested that oxygenation of the isolated, crystalloid perfused, Langendorff rabbit heart is inadequate and that consequent hypoxia limits mechanical performance. The isolated working rabbit heart, which has a higher oxygen requirement than the Langendorff preparation, was used to investigate the relationships between the ability of the heart to perform external work, myocardial oxygen consumption, and tissue high energy phosphate content. DESIGN:Hearts from adult rabbits (1.5-2.2 kg), paced at 200 beats.min-1, were perfused in the working mode with bicarbonate buffer (1.8 mmol.litre-1 Ca2+; PO2 greater than 85 kPa, 630 mm Hg). MEASUREMENTS AND MAIN RESULTS:The effects of (a) increasing preload (10, 14, 18, 22, 26 cm H2O) at fixed afterload (80 cm H2O) and (b) increasing afterload (60, 80, 100, 120 cm H2O) at fixed preload (18 cm H2O) on left ventricular power and myocardial oxygen consumption were determined. Increasing preload (from 10 to 26 cm H2O) resulted in linear increases in left ventricular power [from 1.36(SEM 0.06) to 2.81(0.19) J.min-1] and myocardial oxygen consumption [from 554(37) to 801(59) microliters.g dry wt-1.min-1]; this was made possible by increased oxygen supply secondary to increased coronary flow. Increasing afterload (from 60 to 120 cm H2O) also increased left ventricular power [from 1.76(0.05) to 2.16(0.09) J.min-1] and myocardial oxygen consumption [from 617(48) to 903(30) microliters.g dry wt-1.min-1]. For a given increase in left ventricular power, the increase in myocardial oxygen consumption was greater if the increased workload was due to an increased afterload than if it was due to an increased preload, suggesting that increasing afterload resulted in a reduced external mechanical efficiency. Prolonged perfusion under conditions of low and high workload (80 and 120 cm H2O afterload for 60 min) was associated with comparable myocardial contents of adenosine triphosphate [22.5(1.4) and 21.7(0.4) mumols.g dry wt-1] and creatine phosphate [21.8(4.5) and 23.7(1.9) mumols.g dry wt-1] and comparable rates of lactate efflux [34.7(13.0) and 36.7(12.5) mumols.g dry wt-1.60 min-1]. CONCLUSION:Our observation of increased myocardial oxygen consumption and comparable contents of high energy phosphates with increased workload would suggest that the crystalloid perfused working rabbit heart is adequately oxygenated.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Murashita T,Kempsford RD,Hearse DJdoi
10.1093/cvr/25.3.198subject
Has Abstractpub_date
1991-03-01 00:00:00pages
198-206issue
3eissn
0008-6363issn
1755-3245journal_volume
25pub_type
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/18.2.75
更新日期:1984-02-01 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
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doi:10.1093/cvr/cvq353
更新日期:2011-04-01 00:00:00
abstract:OBJECTIVE:Preexposure of macrophages to oxidized low-density lipoprotein (oxLDL) attenuates formation of reactive oxygen species (ROS) upon stimulation with phorbol 12-myristate 13-acetate (PMA) or acute exposure to oxLDL. We examined whether attenuation of the oxidative burst is attributed to down-regulation of protei...
journal_title:Cardiovascular research
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更新日期:2006-08-01 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:The aim was to evaluate the hypothesis that the oxygen demand of stimulated myocardium is downregulated and ischaemia avoided when oxygen supply is limited. METHODS:Isoprenaline stimulation during reduced coronary perfusion pressure or moderate coronary hypoxaemia was studied in relation to myocardial oxygen...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/27.8.1542
更新日期:1993-08-01 00:00:00
abstract::Most studies on stem cell transplantation therapy on myocardially infarcted animal models and phase-I human clinical trials have focused on the use of undifferentiated stem cells. There is a strong possibility that some degree of cardiomyogenic differentiation of stem cells in vitro prior to transplantation would resu...
journal_title:Cardiovascular research
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更新日期:2004-04-01 00:00:00
abstract::The importance of the vascular adventitia is increasingly being recognized not only in vascular disease but also in normal maintenance and homeostasis of vessels. Activation of the adventitia and its resident fibrocytic cells in response to injury, stretch, cytokines, and hormones has been shown to stimulate different...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/j.cardiores.2007.06.016
更新日期:2007-09-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(03)00389-4
更新日期:2003-10-15 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00336-8
更新日期:1999-06-01 00:00:00
abstract::The effects of adrenaline on kinetically-distinct compartments of exchangeable calcium in the spontaneously-beating perfused rat heart were investigated under steady-state conditions using a 45Ca2+ outflow technique together with a nonlinear least-squares curve fitting procedure and 51Cr-EDTA to monitor the loss of fr...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/17.2.88
更新日期:1983-02-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(97)00025-4
更新日期:1997-05-01 00:00:00
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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::In this review, we summarize current knowledge on the genetics of coronary artery disease, based on 10 years of genome-wide association studies. The discoveries began with individual studies using 200K single nucleotide polymorphism arrays and progressed to large-scale collaborative efforts, involving more than a 100 ...
journal_title:Cardiovascular research
pub_type: 历史文章,杂志文章,评审
doi:10.1093/cvr/cvy084
更新日期:2018-07-15 00:00:00
abstract:AIMS:Myocardial function is severely compromised during sepsis. Several underlying mechanisms have been proposed. The innate immune system, i.e. toll-like receptor (TLR) 2 and 4, significantly contributes to cardiac dysfunction. Little is known regarding TLR9 and its pathogenic ligand bacterial DNA in the myocardium. W...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvn011
更新日期:2008-04-01 00:00:00
abstract:AIMS:The metabolic syndrome (MS) leads to myocardial fibrosis (MF) and diastolic dysfunction. Statins have proven beneficial effects in MS, but their impact on cardiac remodelling is uncertain. We examined the effects and mechanisms of chronic statin treatment on cardiac remodelling, e.g. fibrosis and diastolic propert...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvt070
更新日期:2013-07-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvaa161
更新日期:2020-06-12 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/19.10.649
更新日期:1985-10-01 00:00:00
abstract:STUDY OBJECTIVE:The aim was to determine whether taurine influences the membrane surface charges in cardiac muscle. DESIGN:Screening of the negative charges at the outside surface of the membrane results in a shift of the steady state inactivation of the sodium system towards less negative potentials. This feature was...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/24.11.918
更新日期:1990-11-01 00:00:00
abstract:STUDY OBJECTIVE:The objectives were (a) to describe the effects of vasoactive drugs in normal rats upon cardiovascular function assessed by computing aortic haemodynamic power and input impedance, each separated into their component parts, and (b) to study the relationship between left ventricular pulsatile power outpu...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/25.11.923
更新日期:1991-11-01 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
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/12.5.309
更新日期:1978-05-01 00:00:00
abstract::The genetic basis of cardiac electrical phenotypes has in the last 25 years been the subject of intense investigation. While in the first years, such efforts were dominated by the study of familial arrhythmia syndromes, in recent years, large consortia of investigators have successfully pursued genome-wide association...
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pub_type: 杂志文章
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更新日期:2020-07-15 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.1.72
更新日期:1994-01-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/27.4.585
更新日期:1993-04-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(02)00601-6
更新日期:2002-12-01 00:00:00
abstract:OBJECTIVE:Norepinephrine (NE) induced hypertrophy and remodelling of the extracellular matrix (ECM) in the left ventricle (LV) of the rat heart with resulting fibrosis. However, there was no increased collagen deposition in the right ventricle (RV). To test the hypothesis that lack of RV fibrosis is the result of eleva...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(02)00700-9
更新日期:2003-02-01 00:00:00
abstract::Systemic haemodynamics and regional myocardial blood flow responses to hypertonic mannitol were studied in 10 conscious and 23 anaesthetized dogs. Mannitol infusion significantly increased regional myocardial blood flow in the conscious, intact dogs. Mannitol increased total coronary flow 20% in anasethetized animals ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/9.1.47
更新日期:1975-01-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvp252
更新日期:2009-12-01 00:00:00
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journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvt080
更新日期:2013-07-01 00:00:00
abstract:AIMS:Expression of extracellular matrix protein CCN1 is induced in end-stage ischaemic cardiomyopathy in humans, and after cardiac ischaemia and reperfusion in experimental animal models. Despite its well-documented angiogenic activities, CCN1 increases the cytotoxicities of the tumour necrosis factor family cytokines,...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvt001
更新日期:2013-04-01 00:00:00