Abstract:
OBJECTIVE:Angiotensin II (ANG II) has recently been reported to increase inotropy in adult rabbit myocytes by a mechanism of alkalinization and consequent increased myofilament sensitivity to calcium. Accordingly, we tested the hypothesis that ANG II would have a greater inotropic effect during ischemic conditions than it would during normoxia, since ischemia-induced intracellular acidosis contributes to ischemic contractile depression by decreasing myofilament calcium sensitivity. METHODS:We studied the effects of ANG II in isolated, red-blood-cell-perfused, isovolumic rat and rabbit hearts during normoxic perfusion conditions and at graded reductions in coronary perfusion pressure (CPP). At each level of perfusion, ANG II was infused at progressively increasing concentrations ranging from 10(-11) to 10(-5) M. The maximal effective ANG II concentration was 10(-7) M. RESULTS:Our studies show that ANG II caused comparable absolute increases in isovolumic LV developed pressure in normoperfused and hypoperfused rabbit hearts. However, since contractile function was markedly depressed in ischemic hearts prior to ANG II administration, the relative inotropic response to ANG II was significantly greater during ischemia than normoxia. Similarly, ANG II had no positive inotropic effect in the rat during normoxia, but increased contractility during ischemia. To assess specifically the potential of ANG II to reverse the negative inotropy of acidosis, normoxic non-ischemic rat hearts were perfused with a hypercarbic acidotic perfusate (pH = 7.1). During the hypercarbic perfusion when contraction was depressed by acidosis, ANG II [10(-7)]M increased LV developed pressure by 19% and +dP/dt by 27% (P < 0.05), in contrast to its lack of intropic effect at a normal pH. The positive inotropic effect observed in rat hearts with ANG II during ischemia was significantly attenuated (P < 0.001) by concomitant infusion with amiloride, 5-(N-ethyl-N-isopropyl) (EIPA), a Na+/H+ exchange inhibitor. CONCLUSIONS:We conclude that during normoxia, ANG II has a different inotropic potency in rabbits from that in rats. In both species, the relative inotropic responsiveness of ANG II is potentiated during low-flow ischemia. These results are consistent with a relative intracellular alkalinization that occurs secondary to ANG II's action to stimulate Na+/H+ exchange.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Libonati JR,Eberli FR,Sesselberg HW,Apstein CSdoi
10.1016/s0008-6363(96)00185-xsubject
Has Abstractpub_date
1997-01-01 00:00:00pages
71-81issue
1eissn
0008-6363issn
1755-3245pii
S0008-6363(96)00185-Xjournal_volume
33pub_type
杂志文章abstract:OBJECTIVES:Annexin A7 is involved in cardiomyocyte membrane organization and Ca(2+)-dependent signalling processes. We investigated the impact of annexin A7 on cardiac electrophysiological properties using an annexin A7-deficient mouse strain (annexin A7(-/-)). METHODS:Nineteen adult annexin A7(-/-) and 14 wild-type m...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2007.07.001
更新日期:2007-11-01 00:00:00
abstract:OBJECTIVES:I(Ks), the slow component of the delayed rectifier potassium current, underlies a strong beta-adrenergic regulation in the heart. Catecholamines, like isoproterenol, induce a strong increase in I(Ks). Recent work has pointed to an opposing biological effect of beta(1)- and beta(3)-adrenoceptors in the heart....
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:AIMS:To describe the overall role of reduced sarcoplasmic reticulum Ca(2+) ATPase (SERCA2) for Ca(2+) wave development. METHODS AND RESULTS:SERCA2 knockout [Serca2(flox/flox) Tg(alphaMHC-MerCreMer); KO] mice allowing inducible cardiomyocyte-specific disruption of the Serca2 gene in adult mice were compared with Serca(...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvp401
更新日期:2010-04-01 00:00:00
abstract:OBJECTIVE:The Na+ activated K+ channel (IK(Na)) may be activated during ischaemia when the intracellular Na+ concentration is raised. As ischaemia is also associated with intracellular acidification, the influence of intracellular pH on this K+ channel was investigated. METHODS:The effects of intracellular Na+ and H+ ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.7.1036
更新日期:1994-07-01 00:00:00
abstract:OBJECTIVE:The aim was to determine if either heparin or N-acetylheparin could reduce the extent of myocardial injury resulting from 90 min of coronary artery occlusion and 6 h of reperfusion in the anaesthetised dog. METHODS:Heparin or N-acetylheparin was given in three repeated intravenous doses of 2 mg.kg-1. Drug or...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-05-01 00:00:00
abstract:BACKGROUND:During reperfusion of ischaemic myocardium, Na+/H+ exchange promotes recovery from acidosis resulting in an accumulation of intracellular Na+. This leads to calcium overload via Na+/Ca2+ exchange and might result in cell necrosis contributing to reperfusion injury. METHODS AND RESULTS:We assessed whether HO...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-12-01 00:00:00
abstract::The hypothalamic-pituitary-adrenal (HPA) axis, like the sympathetic nervous system and the renin-angiotensin-aldosterone (RAA) system, sustains life in stressful situations by increasing vascular tone and ensuring fuel availability. It also modulates inflammation and tissue repair processes. Untoward cardiovascular ef...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/j.cardiores.2004.07.006
更新日期:2004-11-01 00:00:00
abstract:AIMS:Sleep disturbances exhibit a strong social patterning, and inadequate sleep has been associated with adverse health outcomes, including cardiovascular disorders (CVD). However, the contribution of sleep to socioeconomic inequalities in CVD is unclear. This study pools data from eight European cohorts to investigat...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz267
更新日期:2020-07-01 00:00:00
abstract:OBJECTIVE:Pericytes, located in close proximity to the underlying endothelium, form an integral component of the microvasculature. These cells are intimately involved in angiogenesis, which is of fundamental importance in many physiological and pathological processes. We evaluated the influence of pericyte-conditioned ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2005.08.003
更新日期:2006-01-01 00:00:00
abstract:AIMS:Neointimal hyperplasia is a common feature of fibro-proliferative vascular disease and characterizes initial stages of atherosclerosis. Neointimal lesions mainly comprise smooth muscle-like cells. The presence of these lesions is related to local differences in shear stress. Neointimal cells may arise through migr...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvv175
更新日期:2015-12-01 00:00:00
abstract:OBJECTIVE:The sequelae of myocardial ischaemia can in principle be alleviated by repeated reperfusion, but the accumulation of adenosine monophosphate (AMP) and the loss of interstitial adenosine may lead to adenylate depletion. Repeated oxidative stress could predispose the heart to reperfusion injury. The aim of this...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/26.5.502
更新日期:1992-05-01 00:00:00
abstract::Tension and action potentials have been measured simultaneously from isolated cat papillary muscles. Two groups of experiments are described. In the first group, the external conditions under which the muscle contracted were changed. Specifically, stimulation rate, extra-cellular [Ca++], extracellular [Na++] were alte...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/11.3.210
更新日期:1977-05-01 00:00:00
abstract::In acute myocardial infarction (MI), reactive oxygen species (ROS) are generated in the ischaemic myocardium especially after reperfusion. ROS directly injure the cell membrane and cause cell death. However, ROS also stimulate signal transduction to elaborate inflammatory cytokines, e.g. tumour necrosis factor-alpha (...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvn335
更新日期:2009-02-15 00:00:00
abstract::Stroke, ischaemic stroke and subtypes of ischaemic stroke display substantial heritability. When compared with related vascular conditions, the number of established risk loci reaching genome-wide significance for association with stroke is still in the lower range, particularly for aetiological stroke subtypes such a...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvy068
更新日期:2018-07-15 00:00:00
abstract:AIMS:To define the molecular mechanisms of cardiotoxicity induced by Sunitinib and to identify the role of biological sex in modulating toxicity. METHODS AND RESULTS:Exposure of isolated cardiomyocytes to plasma-relevant concentrations of Sunitinib and other tyrosine kinase inhibitors produces a broad spectrum of abno...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvv152
更新日期:2015-07-01 00:00:00
abstract:AIMS:It has been reported that laminar shear flow (LF) improves barrier functions in vascular endothelial cells (ECs), whereas disturbed flow (DF) impairs the barrier. Our previous study showed that LF stimulus led to the activation of the cysteine protease, m-calpain, in ECs, which can influence RhoA activity. We hypo...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvp311
更新日期:2010-02-01 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::Vascular smooth muscle cells (vSMCs) play a crucial role in both the pathogenesis of Aneurysms and Dissections of the ascending thoracic aorta (TAAD) in humans and in the associated adaptive compensatory responses, since thrombosis and inflammatory processes are absent in the majority of cases. Aneurysms and dissectio...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvy006
更新日期:2018-03-15 00:00:00
abstract:OBJECTIVE:Increased expression of the cardiac natriuretic peptides (NP), atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) is observed during chronic hemodynamic overload. The mechanisms underlying this process are not fully understood. In vitro, endothelin 1 (ET-1) is a powerful stimulator of cardiac...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(00)00311-4
更新日期:2001-03-01 00:00:00
abstract:OBJECTIVE:Lower limb perfusion following arterial occlusion depends on the recruitment of collateral vessels. Blood flow through these collateral vessels may be jeopardized by hypersensitivity to vasoconstriction by serotonin (5-HT), as has been reported during hyperlipidemia and diabetes. Therefore the aim of this stu...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(02)00538-2
更新日期:2002-11-01 00:00:00
abstract::Ischemic preconditioning is a powerful biologic phenomenon that activates innate cell survival programs to protect the heart from ischemic injury. The preponderance of research into classical ischemic preconditioning has focused on signaling pathways orchestrating cardioprotection. Conceptually classified into trigger...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(03)00337-7
更新日期:2003-07-01 00:00:00
abstract:AIMS:Polyunsaturated fatty n-3 acids (PUFAs) have been reported to exhibit antiarrhythmic properties. However, the mechanisms of action remain unclear. We studied the electrophysiological effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on IKs, and on the expression and location of Kv7.1 and KCNE1....
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvu250
更新日期:2015-02-01 00:00:00
abstract::Platelet-activating factor might be responsible for the alterations of diastolic function observed in different disease states and these potential effects have not been studied. The effect of incremental concentrations of platelet-activating factor (to a maximum of 200 nM) was therefore examined in isolated perfused r...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(95)00181-6
更新日期:1995-12-01 00:00:00
abstract:OBJECTIVE:The aim was to investigate the influence of coronary occlusion on myocardial interstitial noradrenaline levels in the ischaemic and non-ischaemic regions, using the dialysis technique. METHODS:In nine anaesthetised cats, regional ischaemia was produced by occlusion of the left anterior descending coronary ar...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/27.5.817
更新日期:1993-05-01 00:00:00
abstract:OBJECTIVE:Myocardial contractility is enhanced in transgenic (TG) mice with cardiac-restricted overexpression of the alpha1A-adrenergic receptors (alpha1A-AR). We tested the hypothesis that this enhanced inotropy protects against dysfunction and remodeling after myocardial infarction (MI). METHODS:We subjected alpha1A...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2006.06.015
更新日期:2006-09-01 00:00:00
abstract::An isolated working rat heart preparation was used to characterise the temperature-dependency of the anti-ischaemic properties of nifedipine. In this study hearts were subjected to pre-ischaemic infusion with the St Thomas' cardioplegic solution with or without added nifedipine (0.075 mumol X litre-1). Hearts were the...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/19.2.95
更新日期:1985-02-01 00:00:00
abstract:OBJECTIVES:Angiotensin converting enzyme (ACE) activity in the plasma does not change significantly with hypertension in two-kidney, one-clip hypertensive (2K-1C) rats. However, heart ACE activity and mRNA increase with hypertension. We measured the ACE activity and mRNA in hypertrophied hearts at different times after...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1995-08-01 00:00:00
abstract:OBJECTIVE:Persistent atrial fibrillation (AF) results in an impairment of atrial function. In order to elucidate the mechanism behind this phenomenon, we investigated the gene expression of proteins influencing calcium handling. METHODS:Right atrial appendages were obtained from eight patients with paroxysmal AF, ten ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(99)00045-0
更新日期:1999-05-01 00:00:00
abstract::Effects of sublingual glyceryl trinitrate (GTN) were studied in ten patients without heart failure during diagnostic cardiac catheterisation following angiography. GTN caused substantial reduction in peak left ventricular and aortic pressure (19 mmHg) with lesser reduction in mean aortic pressure (9 mmHg) and no chang...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/20.2.153
更新日期:1986-02-01 00:00:00
abstract:AIMS:Percutaneous implantation has already been used clinically and is a great option for treating young patients. The use of autologous tissue-engineered valved stents might solve the problem of degeneration and limited durability of biological heart valves. METHODS AND RESULTS:Porcine pulmonary heart valves and smal...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvq212
更新日期:2010-12-01 00:00:00