Abstract:
STUDY OBJECTIVE:The aim was to record diastolic transmitral pressure gradients at high sensitivity to quantitate the effect on transmitral pressure gradients of changing the heart rate. DESIGN:Diastolic left atrial and left ventricular pressures were recorded at high sensitivity (40 mm Hg = 10 mm recorded deflection) in control conditions (heart rate 70 beats.min-1) and after intravenous administration of atropine or isoprenaline (heart rate 110 beats.min-1). A special ventricular extrasystole protocol enabled the zero level of the transmitral pressure gradients to be unequivocally determined at high heart rates. The effect of atropine and isoprenaline on the pressure gradients, absolute diastolic pressures, and diastolic time intervals was investigated. EXPERIMENTAL MATERIAL:16 mongrel dogs, 16-25 kg, were used. MEASUREMENTS AND RESULTS:Below a heart rate of 110 beats.min-1, four distinct periods were identified, during which a pressure gradient existed. During early and late diastole, a positive pressure gradient was consistently followed by a negative pressure gradient. Mean negative pressure gradient during early diastole correlated with the pressure difference of rapid filling wave (r = 0.72, p less than 0.01) and with mean positive pressure gradient during early diastole (r = 0.66, p less than 0.01). At a heart rate of 110 beats.min-1, isoprenaline augmented, while atropine reduced, the mean positive pressure gradient during early diastole without affecting the time interval over which the gradient occurred. This divergent action of the two drugs was related to their different effects on the decay of left ventricular pressure, which fell faster and deeper with isoprenaline but not with atropine. Both drugs shortened the time interval of the negative pressure gradient in early diastole without significantly affecting the mean negative pressure gradient during this period. In late diastole, atropine augmented the mean positive pressure gradient more than isoprenaline, reflecting the higher afterload after administration of atropine. Neither drug affected the time interval of the positive pressure gradient. As a result of a shortening of the P-R interval, isoprenaline shortened the time interval of the negative pressure gradient and reduced its mean value. Such an effect was not observed with the dose of atropine used. CONCLUSIONS:We conclude that a pressure gradient reversal in early diastole is always observed below a heart rate of 110 beats.min-1 and that isoprenaline and atropine affect the pattern of transmitral pressure gradients in a different way.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Carmeliet P,Aubert A,Van de Werf F,De Geest Hdoi
10.1093/cvr/24.7.560subject
Has Abstractpub_date
1990-07-01 00:00:00pages
560-9issue
7eissn
0008-6363issn
1755-3245journal_volume
24pub_type
杂志文章abstract::Physical training has been advocated to minimize the problems associated with coronary heart disease; however, the responsible mechanisms are obscure. Rats trained to run on a treadmill were subjected to acute conditions of hypoxia and myocardial ischaemia. Trained rats were better able to maintain a higher level of c...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/10.3.359
更新日期:1976-05-01 00:00:00
abstract::Estimation of infarct size from enzyme activities in plasma or serum presupposes known values of circulatory parameters such as the extravascular distribution volume Ve and the permeability constant P for the transport of enzyme between intravascular volume Vi and Ve. In man, parameter values are used that are extrapo...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/13.10.578
更新日期:1979-10-01 00:00:00
abstract:AIMS:Adequate microcirculatory perfusion, and not just opening of occluded arteries, is critical to salvage heart tissue following myocardial infarction. However, the degree of microvascular perfusion taking place is not known, limited primarily by an inability to directly image coronary microcirculation in a beating h...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz118
更新日期:2019-11-01 00:00:00
abstract:OBJECTIVE:We have attempted to demonstrate the induction of inducible nitric oxide synthase in human vascular tissue and define the capacity of different cytokines to induce this enzyme. METHODS:Segments of human arteries were stimulated with lipopolysaccharide (10 micrograms/ml), interleukin-1 beta (5 U/ml), tumor ne...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00054-6
更新日期:1998-06-01 00:00:00
abstract:AIMS:Diabetes impinges upon mechanisms of cardiovascular repair. However, the biochemical adaptation of cardiac stem cells to sustained hyperglycaemia remains largely unknown. Here, we investigate the molecular targets of high glucose-induced damage in cardiac progenitor cells (CPCs) from murine and human hearts and at...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvs291
更新日期:2013-01-01 00:00:00
abstract::Although fully explored in larger animals, the role of injection site and sample microsphere content on variability of coronary blood flow (CBF) measurement using the microsphere technique remains controversial in rats despite the fact that this species is extensively used in cardiovascular research. We therefore inve...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/23.5.443
更新日期:1989-05-01 00:00:00
abstract:OBJECTIVE:Current guidelines are controversial regarding exercise intensity in cardiovascular prevention and rehabilitation. Although high-intensity training induces larger increases in fitness and maximal oxygen uptake (VO(2max)), moderate intensity is often recommended as equally effective. Controlled preclinical stu...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2005.03.010
更新日期:2005-07-01 00:00:00
abstract:AIM:Age and injury cause structural and functional changes in coronary artery smooth muscle cells (caSMCs) that influence the pathogenesis of coronary artery disease. Although paracrine signalling is widely believed to drive phenotypic changes in caSMCs, here we show that developmental origin within the fetal epicardiu...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvv167
更新日期:2015-07-15 00:00:00
abstract::Protein kinase A (PKA) is a central regulator of cardiac performance and morphology. Myocardial PKA activation is induced by a variety of hormones, neurotransmitters and stress signals, most notably catecholamines secreted by the sympathetic nervous system. Catecholamines bind β-adrenergic receptors to stimulate cAMP-...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvab008
更新日期:2021-01-23 00:00:00
abstract::The heart responds to ischaemic stimuli with release of negative inotropic mediators such as cytokines, platelet-activating factor, oxygen free radicals, arachidonic acids, nitric oxide, adenosine, and still unidentified "cardiodepressant factors" that modulate myocardial performance via autocrine and paracrine coupli...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(01)00420-5
更新日期:2002-01-01 00:00:00
abstract:OBJECTIVE:We recently demonstrated in our swine model of coronary artery spasm that enhanced myosin light chain (MLC) phosphorylations (both MLC mono- and diphosphorylations) play a central role in the pathogenesis of the spasm. However, the molecular mechanism for and the phosphorylation sites for the enhanced MLC pho...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(99)00144-3
更新日期:1999-09-01 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:STUDY OBJECTIVE:The aim of the study was to examine, in a whole heart preparation, the relationship between length changes in cardiac muscle and tension development and length dependent activation. DESIGN:Rat hearts were perfused by the Langendorff technique and isovolumetric pressure changes in the left ventricle, pr...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/24.3.254
更新日期:1990-03-01 00:00:00
abstract::The effect of catheterisation on the rabbit aortic wall is investigated employing a technique identical to that used for continuous monitoring of blood pressure in humans. The catheters were introduced into the aorta through the right femoral artery of the rabbit using the Seldinger technique, except that the catheter...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/13.9.541
更新日期:1979-09-01 00:00:00
abstract:OBJECTIVE:The aim was to evaluate in a minipig model of acute myocardial infarction the cardioprotection provided by the beta adrenoceptor blocking and vasodilating activities present in carvedilol; comparison was made to the pure beta adrenoceptor antagonist, propranolol. METHODS:Experiments were performed in 25 Yuca...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/26.5.518
更新日期:1992-05-01 00:00:00
abstract::The response of a simple systolic time interval, the interval between the Q wave and the onset of the aortic blood pressure pulse (the QA interval), to changes in cardiac contractility, cardiac loading, and heart rate was evaluated in anaesthetised open chest dogs. The QA interval was found to be sensitive to increase...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/20.6.444
更新日期:1986-06-01 00:00:00
abstract:OBJECTIVE:We studied the effects of temporary myocardial ischemia and reperfusion on myocyte injury and ventricular remodelling in wildtype and intercellular adhesion molecule-1- (ICAM-1) deficient mice. METHODS:ICAM-1-/- and ICAM-1+/+ mice were subjected to 30 min of myocardial ischemia and subsequent reperfusion for...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(00)00261-3
更新日期:2001-02-01 00:00:00
abstract::Blood flow autoregulation results from the ability of resistance arteries to reduce or increase their diameters in response to changes in intravascular pressure. The mechanism by which arteries maintain a constant blood flow to organs over a range of pressures relies on this myogenic response, which defines the intrin...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvs152
更新日期:2012-07-15 00:00:00
abstract:OBJECTIVE:We recently showed that mitochondrial coupling factor 6 (CF6) is present as a pressor substance and a prostacyclin inhibitor in systemic circulation. However, the regulation mechanism for circulating CF6 is unknown. We investigated the role of tumor necrosis factor-alpha (TNF-alpha) in the generation and rele...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2004.01.031
更新日期:2004-06-01 00:00:00
abstract:OBJECTIVE:Impairment of endothelium-dependent relaxation is related to dyslipidemia and may be an early marker for atherosclerosis in angiographically smooth arteries. The aim of the present study was to relate preoperative serum lipids to endothelium-dependent relaxation in internal mammary arteries of patients underg...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(97)00081-3
更新日期:1997-06-01 00:00:00
abstract::Platelet-dependent thrombus formation is a key event in the pathogenesis of acute myocardial infarction (AMI). Platelets mediate both thrombotic occlusion of the entire epicardial coronary artery and also accumulate in the microcirculation resulting in impairment of microcirculation and provoking myocardial ischemia d...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/j.cardiores.2003.11.036
更新日期:2004-02-15 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::We studied the effects of intracoronary vasopressin on the relationship between pressure and flow in the coronary circulation of anaesthetised swine. In addition to measurements at control levels, diastolic pressure-flow relationships were constructed from steady-state points below a coronary pressure of 50 mmHg, wher...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/19.7.433
更新日期:1985-07-01 00:00:00
abstract::In this study we report about the modulation of connexin45 (Cx45) gap junction channel properties by phosphorylation of the connexin molecules through different protein kinases. Phosphorylation of Cx45 was studied in HeLa cells transfected with mouse Cx45 (mCx45). Using Western blotting (WB) and immunocytochemistry, t...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(00)00047-x
更新日期:2000-06-01 00:00:00
abstract:AIMS:SR-B1 is a cholesterol transporter that exerts anti-atherogenic properties in liver and peripheral tissues in mice. Bone marrow (BM) transfer studies suggested an atheroprotective role in cells of haematopoietic origin. Here, we addressed the specific contribution of SR-B1 in the monocyte/macrophage. METHODS AND ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz138
更新日期:2020-03-01 00:00:00
abstract:OBJECTIVE:Some neuropeptides have direct cardiac effects and also modulate the cardiac effects of catecholamines. Vasopressin is an abundantly available neuropeptide having well known interactions with catecholamines in vascular smooth muscle. The aim of this study was to determine the direct and modulatory effects of ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/27.9.1624
更新日期:1993-09-01 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::An oscillatory current (Ios) can be recorded after depolarising clamps of a given amplitude and duration. To determine whether Ios depends on other currents activated during the clamp, the Ios was investigated in the absence and in the presence of 4-aminopyridine (4-AP) and cesium (Cs). The following results were obta...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/16.11.637
更新日期:1982-11-01 00:00:00
abstract::The effect on the microcirculation of long term administration of the alpha 1 blocker prazosin, which increases peripheral blood flow, was studied in skeletal muscles with differing metabolic profiles. Prazosin (50 mg.litre-1), given ad libitum for 5 weeks in the drinking water, resulted in an increase in capillarity ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/23.11.913
更新日期:1989-11-01 00:00:00
abstract::In this review, the regional heterogeneity of the oxygen supply-consumption ratio within the heart is discussed. This is an important functional parameter because it determines whether regions within the heart are normoxic or dysoxic. Although the heterogeneity of the supply side of oxygen has been primarily described...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(99)00231-x
更新日期:1999-12-01 00:00:00