Abstract:
:In isolated right atria of the rabbit heart, we studied the activation pattern within the sinus node, using the microelectrode technique. After the electrophysiological experiments, the preparations were subjected to a correlative morphological investigation, using light or electron microscopy. Different criteria for defining the dominant pacemaker were compared. A group of at least 5000 cells, located within the central part of the node where the most characteristic tissue architecture was found, was considered to be responsible for generation of the impulse. At the ultrastructural level, this leading cell group appeared to be part of a larger uniform cell group. The number of gap junctions observed suggests that all nodal cells are coupled by these structures. Toward the periphery, the excitation wave was propagated preferentially in an oblique cranial direction toward the crista terminalis. Neither morphologically nor electrophysiologically specific pathways were found for the conduction, but the preferential direction could be explained by the tissue architecture.
journal_name
Circ Resjournal_title
Circulation researchauthors
Bleeker WK,Mackaay AJ,Masson-Pévet M,Bouman LN,Becker AEdoi
10.1161/01.res.46.1.11subject
Has Abstractpub_date
1980-01-01 00:00:00pages
11-22issue
1eissn
0009-7330issn
1524-4571journal_volume
46pub_type
杂志文章abstract::Bradykinin relaxes arterioles on the brain's surface. This response is endothelium-dependent. The data presented here confirm the hypothesis that hydroxyl free radical mediates this response and may be the endothelium-dependent relaxing factor for bradykinin in this microvascular bed. The response to a locally applied...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.61.4.601
更新日期:1987-10-01 00:00:00
abstract::Inwardly rectifying K+ (Kir) channels are responsible for maintaining endothelial membrane potential and play a key role in endothelium-dependent vasorelaxation. In this study, we show that endothelial Kir channels are suppressed by hypercholesterolemic levels of lipoproteins in vitro and by serum hypercholesterolemia...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000218776.87842.43
更新日期:2006-04-28 00:00:00
abstract::Glibenclamide, one of the antidiabetic sulfonylureas, is known to block ATP-dependent K+ channels. We used this drug to determine to what extent K+ loss from acutely ischemic myocardium is mediated via these channels. We also investigated whether glibenclamide would influence ischemic arrhythmias. Isolated rat hearts ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.2.478
更新日期:1990-02-01 00:00:00
abstract::We stimulated the aortic chemoreceptors in dogs that were anesthetized with chloralose and artificially ventilated by perfusing the isolated aortic arch with venous blood. Inotropic responses were determined by measuring the maximum rate of change of left ventricular pressure (dP/dt max) with aortic pressure and heart...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.46.1.77
更新日期:1980-01-01 00:00:00
abstract::Modulation of the inward Na+ current (I(Na)) by protein kinase C (PKC) was investigated by intracellular perfusion of a peptide corresponding to the catalytic subunit of PKC (PKCP). The effects of PKC activation independent of membrane-receptor pathways were studied in neonatal rat ventricular myocytes using whole-cel...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.81.3.380
更新日期:1997-09-01 00:00:00
abstract::Adipose tissue (AT) can accumulate macrophages and secrete several inflammatory mediators. Despite its pivotal role in the progression of chronic inflammatory processes such as atherosclerosis, the adaptive role of immunity in obesity remains poorly explored. Visceral AT of diet-induced obese C57BL/6 mice had higher n...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.108.177105
更新日期:2008-08-29 00:00:00
abstract::Vascular smooth muscle cells (VSMCs) proliferate in response to arterial injury. Recent findings suggest that, in addition to platelet-derived growth factors, growth factors from inflammatory cells and endothelial cells at the site of injury may contribute to VSMC proliferation. We hypothesized that a common mechanism...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.70.3.593
更新日期:1992-03-01 00:00:00
abstract::We recently established a new transgenic mouse model with brain-restricted overexpression of angiotensin II (Ang II) type 1a receptors (NSE-AT(1a)) to unmask the role of the brain renin-angiotensin system in hypertension. To test the hypothesis that these mice would exhibit an early exacerbation of renovascular hypert...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000140892.86313.c2
更新日期:2004-09-03 00:00:00
abstract::Leukocyte-derived microparticles (LMPs) may originate from neutrophils, monocytes/macrophages, and lymphocytes. They express markers from their parental cells and harbor membrane and cytoplasmic proteins as well as bioactive lipids implicated in a variety of mechanisms, maintaining or disrupting vascular homeostasis. ...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.110.233403
更新日期:2012-01-20 00:00:00
abstract::To test the hypothesis that early interventional treatment with insulin-like growth factor-1 (IGF-1) alleviates subsequent development of dilated cardiomyopathy, cardiac-specific IGF-1 expression was introduced by selective cross-breeding into a transgenic mouse model of heart failure that displays phenotypic characte...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000013780.77774.75
更新日期:2002-04-05 00:00:00
abstract::The epicardium, the tissue layer covering the cardiac muscle (myocardium), develops from the proepicardium, a mass of coelomic progenitors located at the venous pole of the embryonic heart. Proepicardium cells attach to and spread over the myocardium to form the primitive epicardial epithelium. The epicardium subseque...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.111.245589
更新日期:2011-12-09 00:00:00
abstract::Transcriptional thyroid hormone responsiveness of the cardiac alpha-myosin heavy chain (alpha-MHC) gene has been demonstrated in transfections into fetal and neonatal cardiomyocytes and in transgenic mice. However, the correspondence between the regulation of MHC expression in dissociated cells with that in the intact...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.72.6.1211
更新日期:1993-06-01 00:00:00
abstract:RATIONALE:Lymphatic vessels in the respiratory tract normally mature into a functional network during the neonatal period, but under some pathological conditions they can grow as enlarged, dilated sacs that result in the potentially lethal condition of pulmonary lymphangiectasia. OBJECTIVE:We sought to determine wheth...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.114.303119
更新日期:2014-02-28 00:00:00
abstract::Using alpha-chloralose-anesthetized cats, we studied blood pressure and heart rate responses to static contraction and passive stretch of the triceps surae muscle before and after microdialyzing the mu-opioid agonist [D-Ala2]-methionine enkephalinamide (DAME, 200 mumol/L) into the L-7 dorsal horn of the spinal cord. I...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.77.2.326
更新日期:1995-08-01 00:00:00
abstract::Many members of the two-pore-domain potassium (K(+)) channel family have been detected in the mammalian heart but the endogenous correlates of these channels still have to be identified. We investigated whether I(KAA), a background K(+) current activated by negative pressure (stretch) and by arachidonic acid (AA) and ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/hh1601.094979
更新日期:2001-08-17 00:00:00
abstract:RATIONALE:The participation of endothelial cells (EC) in many physiological and pathological processes is widely modeled using human EC cultures, but genetic manipulation of these untransformed cells has been technically challenging. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated p...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.117.306290
更新日期:2015-07-03 00:00:00
abstract::Rat lungs were inflated and incubated in either anionic or cationic ferritin, and alveolar and capillary basement membranes were examined by electron microscopy. Cationic ferritin bound to heparan sulfate proteoglycans on the external surface of the alveolar basement membrane, whereas cationic ferritin bound to the la...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.55.2.155
更新日期:1984-08-01 00:00:00
abstract::Voltage-gated L-type Ca(2+) channels (LCCs) provide Ca(2+) ingress into cardiac myocytes and play a key role in intracellular Ca(2+) homeostasis and excitation-contraction coupling. We investigated the effects of a constitutive increase of LCC density on Ca(2+) signaling in ventricular myocytes from 4-month-old transg...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/hh0202.103230
更新日期:2002-02-08 00:00:00
abstract::Experiments were designed to determine the contribution of endothelial cells to the heterogeneous behavior of the arterial and venous wall. Rings of canine femoral, pulmonary, saphenous, and splenic arteries and veins, with and without endothelium, were mounted for isometric tension recording in Krebs-Ringer bicarbona...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.51.4.439
更新日期:1982-10-01 00:00:00
abstract::Basic calcium phosphate (BCP) crystal deposition underlies the development of arterial calcification. Inflammatory macrophages colocalize with BCP deposits in developing atherosclerotic lesions and in vitro can promote calcification through the release of TNF alpha. Here we have investigated whether BCP crystals can e...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000171451.88616.c2
更新日期:2005-06-24 00:00:00
abstract::Atherosclerotic lesion development seems to be inflammatory in nature and involves the recruitment of monocytes to the vessel wall. In this study, we investigated the role of vascular cell adhesion molecule-1 (VCAM-1) and fibronectin (FN) connecting segment-1 containing the amino acid sequence ILDV as functional ligan...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.87.2.153
更新日期:2000-07-21 00:00:00
abstract::We performed experiments to determine whether or not acetylcholine exerts a prejunctional inhibitory effect on adrenergic neurotransmission in the human blood vessel wall. Rings of human greater saphenous veins were prepared 2 to 15 hours after death and mounted for isometric tension recording in organ chambers filled...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.49.2.337
更新日期:1981-08-01 00:00:00
abstract::The purpose of this study was to evaluate the limitations of the double sucrose gap voltage clamp technique in the determination of tension-voltage relationships for frog atrial muscle. Tension-voltage relationships were determined under two conditions. In one case we determined both the tension response and slow inwa...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.39.1.106
更新日期:1976-07-01 00:00:00
abstract::Ultrarapid freezing has been applied to monitor the structure of the freeze-fractured myocardial sarcolemma. Our two goals were to demonstrate that large areas of membrane can be preserved free of visible ice crystal damage and, thus, be amenable to quantitative analysis and to compare the structure of directly frozen...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.61.1.141
更新日期:1987-07-01 00:00:00
abstract::The deposition of microspheres in small tissue regions is not strictly flow dependent. In comparison with the soluble flow marker 2-iododesmethylimipramine (IDMI), deposition of 16.5-microns microspheres was mildly but systematically biased into high flow regions of rabbit hearts (Bassingthwaighte JB, Malone MA, Moffe...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.5.1328
更新日期:1990-05-01 00:00:00
abstract::Several time- and voltage-dependent ionic currents have been identified in cardiac pacemaker cells, including Na(+) current, L- and T-type Ca(2+) currents, hyperpolarization-activated cation current, and various types of delayed rectifier K(+) currents. Mathematical models have demonstrated that spontaneous action pot...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/01.res.87.2.88
更新日期:2000-07-21 00:00:00
abstract::The alpha-adrenergic blocking drugs, phentolamine and Hydergine, both act centrally at different sites to depress and enhance the pressor and sympathetic nerve response to decreased baroreceptor afferent input in anesthetized cats. Depression of the rise in blood pressure and sympathetic nerve discharge during bilater...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.39.5.724
更新日期:1976-11-01 00:00:00
abstract::To investigate the functional consequences of a tropomyosin (TM) mutation associated with familial hypertrophic cardiomyopathy (FHC), we generated transgenic mice that express mutant alpha-TM in the adult heart. The missense mutation, which results in the substitution of asparagine for aspartic acid at amino acid posi...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.85.1.47
更新日期:1999-07-09 00:00:00
abstract::Ischemia and simulated ischemic conditions induce enhanced release of norepinephrine (NE) in the brain and the heart. Although studies with neuronal preparations demonstrated a rise in [Ca2+]i under energy-depleted conditions, such release of NE in the heart appears to be predominantly Ca2+ independent. Since Ca2+ ove...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.80.2.179
更新日期:1997-02-01 00:00:00
abstract:RATIONALE:The ventricular conduction system (VCS) rapidly propagates electrical impulses through the working myocardium of the ventricles to coordinate chamber contraction. GWAS (Genome-wide association studies) have associated nucleotide polymorphisms, most are located within regulatory intergenic or intronic sequence...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.119.315313
更新日期:2019-08-30 00:00:00