Abstract:
:We have previously shown that a cryoactivatable inactive form of renin, which we have tentatively termed prorenin, occurs in human plasma. Plasma prorenin is measured by subtracting the endogenous plasma renin activity (PRA) from the total renin activity measured after cryoactivation. Cryoactivation is accomplished by shaking plasma at -5 degrees C for 4 days. Circulating prorenin averaged 5.6 +/- 0.8 (SE) ng/ml per hour in a group of 30 normal subjects and 5.1 +/- 1.0 ng/ml per hour in 25 hypertensive subjects during random sodium intake. In these two groups, prorenin ranged from zero to 36 times the endogenous renin level, averaging 2.5-fold in normal subjects and 3.4-fold in hypertensive subjects. During sodium deprivation prorenin more than doubled in 12 hypertensive subjects from a mean of 2.8 to 6.3 ng/ml per hour. In 25 anephric subjects, circulating prorenin was slightly lower than in normal subjects, averaging 3.4 +/- 0.9 ng/ml per hour (P less than 0.05). In contrast to our findings in nephric subjects, the low level of PRA measured in anephric subjects ((0.26 +/- 0.04 ng/ml per hour) was almost always a constant fraction of the measured prorenin. This led to the demonstration that prorenin can be inadvertently activated by chilling blood during processing for renin measurement and this often accounts for the small amount of renin measured in plasmas from anephric subjects. The error in routine PRA measurements due to inadvertent activation averaged +48% in anephric subjects and +17% in those with kidneys. Evaluation of the effect of processing bloods at room temperature revealed that net angiotensin I accumulation is less than 2% of that generated during incubation and can be ignored. Accordingly, to avoid the inadvertent activation of prorenin which can at times lead to a sizable and variable overestimation of PRA we recommend collecting and processing blood samples at room temperature and then storage of plasma completely frozen until the time for analysis.
journal_name
Circ Resjournal_title
Circulation researchauthors
Sealey JE,Moon C,Laragh JH,Atlas SAsubject
Has Abstractpub_date
1977-05-01 00:00:00pages
I41-5issue
5 Suppl 1eissn
0009-7330issn
1524-4571journal_volume
40pub_type
杂志文章abstract::The objective of this study was to elucidate the mechanisms associated with the reciprocal relation between magnesium and calcium on vascular smooth muscle tone in bovine pulmonary artery and vein. Rapid removal of magnesium from Krebs-bicarbonate medium used to bathe isolated rings of precontracted artery or vein cau...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.2.355
更新日期:1990-02-01 00:00:00
abstract::Mechanical forces participate in morphogenesis from the level of individual cells to whole organism patterning. This article reviews recent research that has identified specific roles for mechanical forces in important developmental events. One well defined example is that dynein-driven cilia create fluid flow that de...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.108.175331
更新日期:2008-08-01 00:00:00
abstract::Blood pressure (BP) control in patients with hypertension is variable worldwide, and in general, it results largely unsatisfactory. Factors responsible for this phenomenon include insufficient national cardiovascular healthcare policies for prevention, poor patient compliance with prescribed treatment schedules, and t...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.118.313294
更新日期:2019-03-29 00:00:00
abstract::Cardiovascular aging is associated with decreased endothelial vasoreactivity and prolonged diastolic relaxation. As diminished NO signaling contributes to age-associated endothelial dysfunction, we tested the hypothesis that impaired NO signaling or bioactivity also contributes to slowed ventricular relaxation with ag...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.88.1.97
更新日期:2001-01-19 00:00:00
abstract::Although isoform-selective translocation of protein kinase C (PKC) epsilon appears to play an important role in the late phase of ischemic preconditioning (PC), the mechanism(s) responsible for such translocation remains unclear. Furthermore, the signaling pathway that leads to the development of late PC after exogeno...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.84.5.587
更新日期:1999-03-19 00:00:00
abstract::We studied the effect of histamine and H1 or H2 blockers on the diameter of pial arteries (39-227 micron) using microapplication into the perivascular space. Concentration-response curves for histamine showed dilations which started at 10(-7) M and were maximal at 10(-5) and 10(-4) M. The H2 blocker, cimetidine, induc...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.44.2.161
更新日期:1979-02-01 00:00:00
abstract::We tested the hypothesis that a parenchymally derived mediator is required for arterioles to exhibit oxygen sensitivity. To that end, the parenchyma was dissected and removed from around hamster cheek pouch arterioles, and the oxygen sensitivity of these "aparenchymal arteriolar segments" was studied, either in vitro,...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.53.4.515
更新日期:1983-10-01 00:00:00
abstract::Angiotensin II (Ang II) has profound effects in the central nervous system (CNS), including promotion of thirst, regulation of vasopressin secretion, and modulation of sympathetic outflow. Despite its importance in cardiovascular and volume homeostasis, angiotensinergic mechanisms are incompletely understood in the CN...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000043501.47934.fa
更新日期:2002-11-29 00:00:00
abstract:RATIONALE:Angiotensin-converting enzyme (ACE)2 opposes the actions of angiotensin (Ang) II by degrading it to Ang 1-7. OBJECTIVE:Given the important role of Ang II/Ang 1-7 in atherogenesis, we investigated the impact of ACE2 deficiency on the development of atherosclerosis. METHODS AND RESULTS:C57Bl6, Ace2 knockout (...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.110.219279
更新日期:2010-10-01 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::The dystrophin glycoprotein complex (DGC) is a specialization of cardiac and skeletal muscle membrane. This large multicomponent complex has both mechanical stabilizing and signaling roles in mediating interactions between the cytoskeleton, membrane, and extracellular matrix. Dystrophin, the protein product of the Duc...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/01.RES.0000126574.61061.25
更新日期:2004-04-30 00:00:00
abstract::The influence of endothelin 1 on intracellular Ca2+ transients and isometric contractions was investigated in ferret papillary muscles loaded with the Ca(2+)-regulated bioluminescent indicator aequorin. In concentrations of 3 x 10(-9) to 1 x 10(-7) M, endothelin produced dose-dependent increases in the amplitudes of b...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.69.3.582
更新日期:1991-09-01 00:00:00
abstract::Tissue factor (TF) is a low-molecular-weight glycoprotein that initiates the extrinsic clotting cascade and is considered a major regulator of arterial thrombogenicity. TF pathway inhibitor (TFPI) is a major physiological inhibitor of TF-initiated coagulation. The aim of this study was to define the complex interplay ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/hh1301.092508
更新日期:2001-07-06 00:00:00
abstract::Focal ectopic activity in cardiac tissue is a key factor in the initiation and perpetuation of tachyarrhythmias. Because myofibroblasts as present in fibrotic remodeled myocardia and infarct scars depolarize cardiomyocytes by heterocellular electrotonic interactions via gap junctions in vitro, we investigated using st...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.107.160549
更新日期:2007-10-12 00:00:00
abstract::Platelet activation is markedly increased during coronary thrombolysis and limits the response to thrombolytic therapy. A possible mediator of platelet activation in this setting is thromboxane (TX) A2, a potent platelet agonist formed in greatly increased amounts during coronary thrombolysis in man. To address this h...
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
abstract::Gap junction pharmacology is a nascent field. Previous studies have identified molecules that enhance intercellular communication, and may offer potential for innovative antiarrhythmic therapy. However, their specific molecular target(s) and mechanism(s) of action remain unknown. Previously, we identified a 34-aa pept...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.200576
更新日期:2009-07-17 00:00:00
abstract::Cardiovascular disease is a major killer in postmenopausal women in the industrialized societies. To investigate the effect of progestogen and 17 beta-estradiol replacement therapy on atherogenesis, we studied 60 cholesterol-fed ovariectomized rabbits for 13 weeks. They were randomly assigned to four groups of 15 rabb...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.70.6.1198
更新日期:1992-06-01 00:00:00
abstract::Postischemic endothelial dysfunction may occur as a result of the effects of endogenous oxidants like hydrogen peroxide. Since endothelium-dependent vasodilator function may be affected by pHi, the effect of hydrogen peroxide on endothelial pHi was examined. Hydrogen peroxide (100 micromol/L for 10 minutes) decreased ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.83.6.644
更新日期:1998-09-21 00:00:00
abstract::We examined the function of the interventricular septum in six open-chest dogs by inserting piezoelectric crystals into the interventricular septum. Continuous ultrasonic recordings showed that the changes in myocardial chord length (MCL) in the septum and free walls of the right and left ventricle were similar during...
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::The role of the Na+-Ca2+ exchanger as a major determinant of cell Ca2+ is well defined in cardiac tissue, and there has been much effort to develop specific inhibitors of the exchanger. We use a novel system to test the specificity of two putative specific inhibitors, KB-R7943 and SEA0400. The drugs are applied to ele...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.0000027529.37429.38
更新日期:2002-07-26 00:00:00
abstract::Mechanoreceptors and chemoreceptors have been identified inside the kidney, but their functional role is still largely unclear. The aim of this study was to investigate whether changes in urine output could modify the discharge rate of renal afferent fibers. Experiments were performed in anesthetized cats in which aff...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.73.5.906
更新日期:1993-11-01 00:00:00
abstract:RATIONALE:Increased sympathetic nerve activity has been linked to the pathogenesis of hypertension in humans and animal models. Enhanced peripheral chemoreceptor sensitivity which increases sympathetic nerve activity has been observed in established hypertension but has not been identified as a possible mechanism for i...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.109.206946
更新日期:2010-02-19 00:00:00
abstract:RATIONALE:autophagy, a bulk degradation process of cytosolic proteins and organelles, is protective during nutrient starvation in cardiomyocytes (CMs). However, the underlying signaling mechanism mediating autophagy is not well understood. OBJECTIVE:we investigated the role of FoxOs and its posttranslational modificat...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.110.227371
更新日期:2010-12-10 00:00:00
abstract::To assess the relation between atrial natriuretic peptide and ventricular dysfunction, we simultaneously measured both atrial and plasma immunoreactive atrial natriuretic peptide concentrations in rats 4 weeks after myocardial infarction induced by left coronary artery ligation. When compared to controls (n = 39), rat...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.59.3.256
更新日期:1986-09-01 00:00:00
abstract::Previous studies have demonstrated that cGMP and cAMP reduce the endothelial permeability for fluids and macromolecules when the endothelial permeability is increased by thrombin. In this study, we have investigated the mechanism by which cGMP improves the endothelial barrier function and examined whether nitric oxide...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.76.2.199
更新日期:1995-02-01 00:00:00
abstract::Inducible nitric oxide synthase (iNOS) protein is expressed in cardiac myocytes of patients and experimental animals with congestive heart failure (CHF). Here we show that iNOS expression plays a role in pressure overload-induced myocardial chamber dilation and hypertrophy. In wild-type mice, chronic transverse aortic...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000264081.78659.45
更新日期:2007-04-13 00:00:00
abstract::Pharmacological evidence indicates that angiotensin (Ang II) converting enzyme inhibitors attenuate cardiovascular responses to sympathetic stimulation. To investigate the physiological significance of this attenuation, the pressor and heart rate responses to bilateral carotid occlusion (BCO) were studied before and a...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.66.3.662
更新日期:1990-03-01 00:00:00
abstract::Changes in cardiac filling pressure (central venous pressure) were measured following carotid occlusion and infusions of catecholamines in awake dogs while cardiac output was held constant. After carotid occlusion in dogs with vagi blocked, central venous pressure increased about 0.8 mm Hg (an estimated decrease in va...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.55.4.440
更新日期:1984-10-01 00:00:00
abstract:RATIONALE:The development of the cardiac outflow tract (OFT) and great vessels is a complex process that involves coordinated regulation of multiple progenitor cell populations. Among these populations, neural crest cells make important contributions to OFT formation and aortic arch remodeling. Although numerous signal...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.111.255067
更新日期:2011-11-11 00:00:00
abstract::It is believed that inotropic agents exert their effects in cardiac muscle via a modulation of Ca2+ cycling; however, the involvement of phospholipase activation and the biochemical pathways participating in inotropic responsiveness remain unclear. The aim of the current study was to determine whether arachidonic acid...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.72.2.376
更新日期:1993-02-01 00:00:00