Abstract:
:Changes in angiotensin-converting enzyme were measured in the lungs of fetal rabbits isolated and perfused in situ at varying ages from 22 days gestation to 7 days of age under controlled conditions of flow, pH, and temperature. Enzyme activity was assessed by infusing bradykinin or angiotensin I in Krebs-Henseleit solution and measuring residual peptide in the effluent by radioimmunoassay. The levels of substrate studied were below those required for enzyme saturation. Lungs of 22 day gestation fetuses removed only one-third of either peptide. The activity at term and in neonatal life resulted in more than 80% peptide removal. The time of the greatest rise in the percent substrate cleared occurs earlier than the time of the greatest increase in lung and body weight. The lower percentage of substrate cleared in early gestation appears to result in part from a limited surface area for enzyme activity in the primitive fetal pulmonary microvascular bed, since morphological studies with fluorescein-tagged anticonverting enzyme antibody demonstrated the presence of enzyme in the lung as early as 17 days of gestation. Electron micrographs of the pulmonary endothelial cell surface reveal that the degree of surface infolding and hence surface area increases with gestation. The higher percentage of substrate cleared in later gestation closely parallels the structural and ultrastructural development of the vascular bed. The presence of converting enzyme in the placenta by the second third of gestation and the large size of the placenta suggest that this organ may be a major locus of converting enzyme activity in the fetus.
journal_name
Circ Resjournal_title
Circulation researchauthors
Stalcup SA,Pang LM,Lipset JS,Odya CE,Goodfriend TL,Mellins RBdoi
10.1161/01.res.43.5.705subject
Has Abstractpub_date
1978-11-01 00:00:00pages
705-11issue
5eissn
0009-7330issn
1524-4571journal_volume
43pub_type
杂志文章,收录出版abstract::Previous studies have demonstrated that expression of p193 and p53 mutants with dominant-interfering activities renders embryonic stem cell-derived cardiomyocytes responsive to the growth promoting activities of the E1A viral oncoproteins. In this study, the effects of p53 and p193 antagonization on cardiomyocyte cell...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000132279.99249.f4
更新日期:2004-06-25 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:RATIONALE:In the myocardium, redox/cysteine modification of proteins regulating Ca(2+) cycling can affect contraction and may have therapeutic value. Nitroxyl (HNO), the one-electron-reduced form of nitric oxide, enhances cardiac function in a manner that suggests reversible cysteine modifications of the contractile ma...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.112.270827
更新日期:2012-09-28 00:00:00
abstract::CD40 is a 48-kDa phosphorylated transmembrane glycoprotein belonging to the TNF receptor superfamily. CD40 has been demonstrated on a range of cell types, and it has an important role in adaptive immunity and inflammation. CD40 has recently been described on platelets but platelet activation by CD40 has not been descr...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000070111.98158.6C
更新日期:2003-05-16 00:00:00
abstract::Rationale: The overuse of antibiotics has been an important clinical issue, and antibiotic exposure is linked to alterations in gut microbiota, which has been related to risks of various chronic diseases such as cardiovascular disease and cancer. Also, duration of antibiotic exposure may be a risk factor of premature ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.119.315279
更新日期:2020-01-31 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.65.1.83
更新日期:1989-07-01 00:00:00
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journal_title:Circulation research
pub_type: 杂志文章
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更新日期:2015-07-03 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2015-01-16 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
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journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.49.1.52
更新日期:1981-07-01 00:00:00
abstract::It has been postulated that cardiopulmonary baroreceptor unloading in humans results in nonuniform activation of the sympathetic nervous system. We reasoned that simultaneous measurements of arterial and venous norepinephrine (NE) spillover and clearance (using NE kinetics), muscle sympathetic neural activity (using m...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.6.1720
更新日期:1990-06-01 00:00:00
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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::We studied the individual and combined effects of extracellular acidosis and increases in extracellular potassium on action potential characteristics and conduction in order to gain a better understanding of the effects of acute ischemia. At each level of potassium between 2.7 and 17 mm, acidosis induced by increasing...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.51.5.614
更新日期:1982-11-01 00:00:00
abstract::Vascular remodeling, rather than vasoconstriction, is believed to account for high vascular resistance in severe pulmonary arterial hypertension (PAH). We have found previously that acute Rho kinase inhibition nearly normalizes PAH in chronically hypoxic rats that have no occlusive neointimal lesions. Here we examined...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000261658.12024.18
更新日期:2007-03-30 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::Congenital heart disease (CHD) is the most common congenital anomaly in newborn babies. Cardiac malformations have been produced in multiple experimental animal models, by perturbing selected molecules that function in the developmental pathways involved in myocyte specification, differentiation, or cardiac morphogene...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.112.300853
更新日期:2013-02-15 00:00:00
abstract::Recent evidence suggests that functional diversity of vascular smooth muscle is produced in part by a differential expression of ion channels. The aim of the present study was to examine the role of Ca(2+)-activated K(+) channels (K(Ca) channels) in the expression of smooth muscle cell functional phenotype. We found t...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.85.9.e33
更新日期:1999-10-29 00:00:00
abstract::Activin is a member of the transforming growth factor-beta superfamily, and it modulates the proliferation and differentiation of various target cells. In this study, we investigated the role of activin in the initiation and progression of human atherosclerosis. The expression of activin, its physiological inhibitor f...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.85.10.931
更新日期:1999-11-12 00:00:00
abstract:RATIONALE:Hypoxia promotes renal damage and progression of chronic kidney disease (CKD). The erythrocyte is the only cell type for oxygen (O2) delivery. Sphingosine 1-phosphate (S1P)-a highly enriched biolipid in erythrocytes-is recently reported to be induced under high altitude in normal humans to enhance O2 delivery...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.119.316298
更新日期:2020-07-17 00:00:00
abstract::Recent advances in our understanding of the contribution of thrombin generation to arterial thrombosis and the role of platelets in venous thrombosis have prompted new treatment paradigms. Nonetheless, bleeding remains the major side effect of such treatments spurring the quest for new antithrombotic regimens with bet...
journal_title:Circulation research
pub_type: 杂志文章,评审
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更新日期:2019-02-01 00:00:00
abstract::The role of prostaglandin production in the control of regenerative function of endothelial progenitor cells (EPCs) has not been studied. We hypothesized that activation of cyclooxygenase (COX) enzymatic activity and the subsequent production of prostacyclin (PGI(2)) is an important mechanism responsible for the regen...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.108.176057
更新日期:2008-07-03 00:00:00
abstract::Volume densities of mitochondria, myofibrils, and unspecified cytoplasm were measured by ultrastructural morphometry in myocardium from dogs, rats, hamsters, mice, and in biopsied tissue from human hearts. Human myocardium was composed of 23% mitochondria, 59% myofibrils, and 18% cytoplasm. Volume densities for mitoch...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.56.3.377
更新日期:1985-03-01 00:00:00
abstract::A surgical technique was developed to place sutures around the pulmonary arteries of young rats (about 1 month old and 100 g body weight). As the operated rats grew, the pulmonary arteries were gradually constricted, leading after 4-6 weeks to the development of severe right ventricular hypertrophy with free wall weig...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.49.6.1300
更新日期:1981-12-01 00:00:00
abstract:RATIONALE:Cardiac muscle adapts to increase workload by altering cardiomyocyte size and function resulting in cardiac hypertrophy. G protein-coupled receptor signaling is known to govern the hypertrophic response through the regulation of ion channel activity and downstream signaling in failing cardiomyocytes. OBJECTI...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.206581
更新日期:2009-11-06 00:00:00
abstract::The study was performed to determine whether there is a structural vascular abnormality in normotensive subjects with hypertensive relatives. We examined maximal vasodilator capacity of forearm resistance vessels in 23 normotensive young men (mean blood pressure 94 +/- 0.4 mm Hg, mean +/- SE) with hypertensive relativ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.50.5.671
更新日期:1982-05-01 00:00:00
abstract::The effects of digoxin on monovalent cation active transport were determined in cardiac tissue obtained from dogs given inotropic, toxic, or lethal doses of digoxin. In hemodynamically monitored dogs, active uptake of the K+ analogue Rb+ was determined in vitro in a control myocardial biopsy, and then in serial biopsi...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.44.1.23
更新日期:1979-01-01 00:00:00
abstract::Three different isoforms of the inhibitory guanine nucleotide-binding protein alpha-subunit (Gi alpha) have been cloned. However, little information on the cardiac-specific expression of these isoforms is available. The deduced amino acid sequence of a full-length Gi alpha 2 complementary DNA from a canine ventricular...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.65.4.1136
更新日期:1989-10-01 00:00:00
abstract::Twenty-one dogs were studied under conditions of normal oxygenation and hypoxia with the microsphere distribution method to determine the effect of arterial oxygen saturation on the regional distribution of cardiac output. The dogs were anesthetized and artifically ventilated. Cannulas were placed in the left ventricl...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.39.3.314
更新日期:1976-09-01 00:00:00
abstract::The sphingolipid metabolites, sphingosine (SPH), SPH 1-phosphate (S1P), and sphingosylphosphorylcholine (SPC), can act as intracellular as well as extracellular signaling molecules. These compounds have been implicated in the regulation of cell growth, differentiation, and programmed cell death in nonmyocytes, but the...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.85.11.1000
更新日期:1999-11-26 00:00:00
abstract::Transient coronary occlusion (15 minutes) does not result in irreversible myocardial injury but is associated with a depression of contractile function sustained for several hours to days ("stunned myocardium"). The defect in the contractile process responsible for this phenomenon has been suggested to be causally rel...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.61.6.834
更新日期:1987-12-01 00:00:00