Abstract:
:The purpose of this study was to examine by freeze-fracture the ultrastructure of intercellular junctions between mouse pulmonary endothelial and epithelial cells, and to relate this fine structure to that deduced from previous physiological and ultrastructural studies using tracer techniques. Junctions between capillary endothelial cells consist of one to three interconnected rows of particles which show occasional discontinuities. Small gap junctions are associated with these rows of particles in the arteriolar end of the capillary bed. At the venular end, the junctions consist of low profile ridges on the protoplasmic fracture (PF) face or complimentary grooves on the exoplasmic fracture (EF) face some of which have a sparse number of associated particles. The vascular junctions are similar to those of vessels in rat omentum and mesentery, and resemble "leaky" junctions described in renal proximal convoluted tubular cells. Tight junctions (zonulae occludentes) between type I pneumocytes or between types I and II pneumocytes consist of a band of interconnecting ridges on the PF face and complimentary interconnecting grooves on the EF face. These continuous epithelial junctions have a structure that is typical of tight occluding junctions. Occasionally zonulae occludentes between type I and type II pneumocytes are discontinuous; this may be the result of cell translocation as pneumocytes are shed into the alveolus. Intravascular perfusion fixation at high pressure (140 cm H2O) had no discernible effect on the structure of endothelial or epithelial junctions. The appearance in our study of freeze-fractured pulmonary endothelial and epithelial junctions reveals clearly the physical basis for the results of ultrastructural tracer and physiological studies which have suggested that it is the alveolar epithelium rather than the endothelium that is the chief permeability barrier to small, water-soluble molecules.
journal_name
Circ Resjournal_title
Circulation researchauthors
Schneeberger EE,Karnovsky MJdoi
10.1161/01.res.38.5.404subject
Has Abstractpub_date
1976-05-01 00:00:00pages
404-11issue
5eissn
0009-7330issn
1524-4571journal_volume
38pub_type
杂志文章abstract::The purpose of this study was to investigate if myogenic responses of isolated coronary arterioles were dependent on an intact, functional endothelium. Arterioles were located in situ by intracoronary perfusion with india ink-gelatin solution and then dissected and cannulated at both ends with glass micropipettes. Int...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.3.860
更新日期:1990-03-01 00:00:00
abstract::Studies were carried out to determine the contribution of cardiopulmonary receptors to the renal responses to head-out water immersion in the nonhuman primate. Immersion to the suprasternal notch was associated with significant increases in central venous pressure, urine flow, and sodium excretion. The increased sodiu...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.42.2.263
更新日期:1978-02-01 00:00:00
abstract:RATIONALE:Oxidative stress is an important contributing factor in several human pathologies ranging from atherosclerosis to cancer progression; however, the mechanisms underlying tissue protection from oxidation products are poorly understood. Oxidation of membrane phospholipids, containing the polyunsaturated fatty ac...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.117.305925
更新日期:2015-07-31 00:00:00
abstract::Propagation in cardiac muscle is faster in the longitudinal than in the transverse axis of the cells. Yet, as a result of the larger upstroke velocity of action potentials propagating transversely, it has been suggested that longitudinal propagation is more vulnerable to block. To study the relation between conduction...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.60.5.780
更新日期:1987-05-01 00:00:00
abstract:RATIONALE:The cardiac inwardly rectifying K(+) current (I(K1)) plays a critical role in modulating excitability by setting the resting membrane potential and shaping phase 3 of the cardiac action potential. OBJECTIVE:This study aims to analyze the effects of nitric oxide (NO) on human atrial I(K1) and on Kir2.1 channe...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.197558
更新日期:2009-08-14 00:00:00
abstract::Osteopontin (OPN) is a cytokine upregulated in diabetic vascular disease. To better understand its role in vascular remodeling, we assessed how OPN controls metalloproteinase (MMP) activation in aortic adventitial myofibroblasts (AMFs) and A7r5 vascular smooth muscle cells (VSMCs). By zymography, OPN and tumor necrosi...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000227550.00426.60
更新日期:2006-06-23 00:00:00
abstract::The aims of the current study were to examine the efficacy of acetylcholine (ACh) to mimic ischemic preconditioning in dogs and to determine the role of nitric oxide (NO), muscarinic receptors, and ATP-sensitive K+ (KATP) channels in mediating its effects. Barbital-anesthetized open-chest dogs were subjected to 60 min...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.73.6.1193
更新日期:1993-12-01 00:00:00
abstract::Accumulation of plasminogen activator inhibitor type 1 (PAI-1) in the arterial wall may accelerate atherogenesis by inhibiting fibrinolysis, diminishing proteolysis of extracellular matrix proteins, or modifying migration of vascular smooth muscle cells. Increased intramural expression of the PAI-1 gene is induced by ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.73.4.671
更新日期:1993-10-01 00:00:00
abstract::The cardiac high molecular weight proteins/ryanodine receptors were purified to homogeneity from junctional sarcoplasmic reticulum membranes and shown to exhibit large conductance calcium channel activity. High molecular weight proteins were solubilized from junctional sarcoplasmic reticulum in zwitterionic detergent ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.64.4.779
更新日期:1989-04-01 00:00:00
abstract::The effects of synthetic human atrial 28-amino acid peptide (alpha-human atrial polypeptide) on systemic and renal hemodynamics were examined in two separate groups of Inactin-anesthetized rats. First, mean arterial pressure, heart rate, and cardiac output were measured before and during infusion of the peptide at rat...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.57.4.634
更新日期:1985-10-01 00:00:00
abstract:RATIONALE:Lymphatic vasculature constitutes a second vascular system essential for immune surveillance and tissue fluid homeostasis. Maturation of the hierarchical vascular structure, with a highly branched network of capillaries and ducts, is crucial for its function. Environmental cues mediate the remodeling process,...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.116.308825
更新日期:2017-04-14 00:00:00
abstract::T-wave alternans (TWA), an ABAB oscillation, has been postulated as the initial pattern in a stepwise progression to higher-order oscillations, culminating in sudden arrhythmic death. The present study is the first to provide experimental evidence to support this intriguing concept. Epicardial and endocardial ECGs fro...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000038887.17976.33
更新日期:2002-10-18 00:00:00
abstract::Previous studies have demonstrated that low shear rates promote leukocyte adherence to microvascular endothelium in postcapillary venules. The objective of this study was to determine whether an accumulation of inflammatory mediators such as platelet activating factor and leukotriene B4 is responsible for shear rate-d...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.71.4.906
更新日期:1992-10-01 00:00:00
abstract::To clarify the physiological role of calcium-activated neutral protease (CANP) in human platelets, we loaded the platelets with a Ca2+ -sensitive fluorescent dye, fura-2, and measured the degree of aggregation, cytosolic calcium ion concentration [( Ca2+]i), and proteolysis by sodium dodecyl sulfate-polyacrylamide gel...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.64.2.407
更新日期:1989-02-01 00:00:00
abstract::The hypothesis that alpha-adrenergic coronary vasoconstriction helps maintain a uniform transmural distribution of myocardial blood flow during exercise was tested in dogs. Carotid artery loops were surgically constructed and a splenectomy performed three weeks prior to study. On the day of study, the dog was anesthet...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.62.2.286
更新日期:1988-02-01 00:00:00
abstract::We report the hemodynamic parameters of stage 18, 21, 24, and 27 chick embryos (from 3 to 5 days of incubation). Dorsal aortic blood velocity and mean vitelline artery blood pressure are measured with a 20 MHz pulsed-Doppler meter and servo-null pressure system respectively. We also measure heart rate, dorsal aortic d...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.51.6.810
更新日期:1982-12-01 00:00:00
abstract::Calcium channel blockers (CCBs), which are used clinically for treatment of angina and hypertension, are known to inhibit calcium influx into arterial smooth muscle cells and thereby decrease smooth muscle cell contraction. In addition, they prevent cholesteryl ester (CE) accumulation, the hallmark of human atheroscle...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.1.185
更新日期:1990-01-01 00:00:00
abstract::Inflammation is a condition that underscores many cardiovascular pathologies including endothelial dysfunction, but no link is yet established between the vascular pathology of the metabolic syndrome with a particular inflammatory cytokine. We hypothesized that impairments in coronary endothelial function in the obese...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000229685.37402.80
更新日期:2006-07-07 00:00:00
abstract::In 26 Wistar rats with surface glomeruli, the determinants of glomerular ultrafiltration and peritubular capillary uptake of proximal reabsorbate were studied before and during intravenous infusions of norepinephrine or angiotensin II. Regardless of whether renal perfusion pressure (AP) was permitted to increase, both...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.37.1.101
更新日期:1975-07-01 00:00:00
abstract::Spatial electrical heterogeneity has a profound effect on normal cardiac electrophysiology and genesis of cardiac arrhythmias in diseased hearts. The Na+-Ca2+ exchanger (NCX) is a key linker, through Ca2+ signaling, between contractility and arrhythmias. Here we characterize the differential transmural expression of N...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000175935.08283.27
更新日期:2005-08-05 00:00:00
abstract::C-reactive protein (CRP), a characteristic inflammatory marker, is a powerful predictor of cardiovascular events. Recent data suggest that CRP may also promote atherogenesis through inducing endothelial dysfunction. Lectin-like oxidized low-density lipoprotein (oxLDL) receptor-1 (LOX-1) is a newly identified endotheli...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000147309.54227.42
更新日期:2004-10-29 00:00:00
abstract::Previously we have shown that AIP1 (apoptosis signal-regulating kinase [ASK]1-interacting protein 1), a novel member of the Ras-GAP protein family, facilitates dephosphorylation of ASK1 at pSer967 and subsequently 14-3-3 release from ASK1, leading to enhanced ASK1-JNK signaling. However, the phosphatase(s) responsible...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.107.168153
更新日期:2008-04-11 00:00:00
abstract::Recent pharmacological studies have shown that perivascular nerves can influence the development and function of vascular endothelial cells (ECs). However, morphological studies have not yet been carried out to investigate whether these functional changes are associated with changes in vasoactive substances in ECs. We...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.79.2.317
更新日期:1996-08-01 00:00:00
abstract::We used a genetic approach to determine whether increasing the level of A3 adenosine receptors (A3ARs) expressed in the heart confers protection against ischemia without causing cardiac pathology. We generated mice carrying one (A3tg.1) or six (A3tg.6) copies of a transgene consisting of the cardiomyocyte-specific alp...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000028007.91385.ee
更新日期:2002-07-26 00:00:00
abstract::Mechanisms of denervation supersensitivity to sympathomimetic amines were studied in conscious animals. Norepinephrine, 0.1 micrograms/kg, increased left ventricular dP/dt significantly more (4208 +/- 828 mm Hg/sec) in dogs with cardiac denervation than in intact dogs (1029 +/- 280 mm Hg/sec), P less than 0.01, wherea...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.57.1.55
更新日期:1985-07-01 00:00:00
abstract:RATIONALE:Myosin light chain (MLC) phosphorylation determines vascular contractile status. In addition to the classic Ca²⁺-dependent MLC kinase (MLCK), another unidentified kinase(s) also contributes to MLC phosphorylation in living cells. Inhibitor κB kinase 2 (IKK2)-deficient mouse embryonic fibroblasts demonstrate a...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.113.301510
更新日期:2013-08-16 00:00:00
abstract::The direct oral anticoagulants (DOACs) represent a major advance in oral anticoagulant therapy and have replaced the vitamin K antagonists as the preferred treatment for many indications. By simplifying long-term anticoagulant therapy and improving its safety, the DOACs have the potential to reduce the global burden o...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.116.306925
更新日期:2016-04-29 00:00:00
abstract::Notch signaling is critically important for proper architecture of the vascular system, and mutations in NOTCH3 are associated with CADASIL, a stroke and dementia syndrome with vascular smooth muscle cell (VSMC) dysfunction. In this report, we link Notch signaling to platelet-derived growth factor (PDGF) signaling, a ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.107.167965
更新日期:2008-06-20 00:00:00
abstract::Protein kinase C (PKC) is a key mediator of many diverse physiological and pathological responses. Although little is known about the specific in vivo roles of the various cardiac PKC isozymes, activation-induced translocation of PKC is believed to be the primary determinant of isozyme-specific functions. Recently, we...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.86.11.1173
更新日期:2000-06-09 00:00:00
abstract:RATIONALE:Cardiac myocyte-specific deletion of either glycogen synthase kinase (GSK)-3α and GSK-3β leads to cardiac protection after myocardial infarction, suggesting that deletion of both isoforms may provide synergistic protection. This is an important consideration because of the fact that all GSK-3-targeted drugs, ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.116.308544
更新日期:2016-04-15 00:00:00