Abstract:
:This study aimed at identifying the type and functional significance of potassium channels and voltage-dependent calcium channels (Ca(v)) in single rat JG cells using whole-cell patch clamp. Single JG cells displayed outward rectification at positive membrane potentials and limited net currents between -60 and -10 mV. Blockade of K+ channels with TEA inhibited 83% of the current at +105 mV. Inhibition of KV channels with 4-AP inhibited 21% of the current. Blockade of calcium-sensitive voltage-gated K+ channels (BKCa) with charybdotoxin or iberiotoxin inhibited 89% and 82% of the current, respectively. Double immunofluorescence confirmed the presence of BKCa and renin in the same cell. cAMP increased the outward current by 1.6-fold, and this was inhibited by 74% with iberiotoxin. Expression of the cAMP-sensitive splice variant (ZERO) of BKCa was confirmed in single-sampled JG cells by RT-PCR. The resting membrane potential of JG cells was -32 mV and activation of BKCa with cAMP hyperpolarized cells on average 16 mV, and inhibition with TEA depolarized cells by 17 mV. The cells displayed typical high-voltage activated calcium currents sensitive to the L-type Ca(v) blocker calciseptine. RT-PCR analysis and double-immunofluorescence labeling showed coexpression of renin and L-type Ca(v) 1.2. The cAMP-mediated increase in exocytosis (measured as membrane capacitance) was inhibited by depolarization to +10 mV, and this inhibitory effect was blocked with calciseptine, whereas K+-blockers had no effect. We conclude that JG cells express functional cAMP-sensitive BKCa channels (the ZERO splice variant) and voltage-dependent L-type Ca2+ channels.
journal_name
Circ Resjournal_title
Circulation researchauthors
Friis UG,Jørgensen F,Andreasen D,Jensen BL,Skøtt Odoi
10.1161/01.RES.0000085041.70276.3Dsubject
Has Abstractpub_date
2003-08-08 00:00:00pages
213-20issue
3eissn
0009-7330issn
1524-4571pii
01.RES.0000085041.70276.3Djournal_volume
93pub_type
杂志文章abstract:RATIONALE:Although PSA (prostate-specific antigen)-a tumor marker for prostate cancer-has been reported to be associated with cardiovascular disease (CVD) risk factors, studies on the association of PSA with subclinical and clinical CVD remain limited. OBJECTIVE:We examined the association of total serum PSA within th...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.118.313413
更新日期:2019-05-10 00:00:00
abstract::Inflammatory cell infiltration is a feature of postischemic neovascularization. However, mechanisms leading to leukocyte attraction to the site of neovascularization are still undefined. We hypothesized that the CXC chemokine receptor 3 (CXCR3) may contribute to leukocyte accumulation and subsequently to blood vessel ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000159389.55544.20
更新日期:2005-03-18 00:00:00
abstract:RATIONALE:MicroRNAs modestly suppress their direct mRNA targets, and these direct effects are amplified by modulation of gene transcription pathways. Consequently, indirect mRNA modulatory effects of microRNAs to increase or decrease mRNAs greatly outnumber direct target suppressions. Because microRNAs are products of ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.113.300975
更新日期:2013-06-21 00:00:00
abstract::Cellular Ca2+ regulation is abnormal in diseased hearts. We designed this study to assess the role of the Na(+)-Ca2+ exchanger in excitation-contraction coupling in surviving myocardium of the infarcted heart. We measured cellular contractions and whole-cell currents in single left ventricular myocytes isolated from t...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.81.6.1083
更新日期:1997-12-01 00:00:00
abstract::Nitric oxide (NO), generated by platelets through stimulation of nitric oxide synthase (NOS), limits platelet adhesion and aggregation after a prothrombotic stimulus. Platelet beta-adrenoceptors (betaARs) mediate inhibition of aggregation, but no direct link has been shown between these receptors and platelet adhesion...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.87.1.39
更新日期:2000-07-07 00:00:00
abstract::The myocardium of the failing heart undergoes a number of structural alterations, most notably hypertrophy of cardiac myocytes and an increase in extracellular matrix proteins, often seen as primary fibrosis. Connective tissue growth factor (CTGF) is a key molecule in the process of fibrosis and therefore seems an att...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.108.182535
更新日期:2009-01-30 00:00:00
abstract::Herein, we show that the paired-related homeobox gene, Prx1, is required for lung vascularization. Initial studies revealed that Prx1 localizes to differentiating endothelial cells (ECs) within the fetal lung mesenchyme, and later within ECs forming vascular networks. To begin to determine whether Prx1 promotes EC dif...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000130656.72424.20
更新日期:2004-06-11 00:00:00
abstract::Ablation of the enzyme phosphoinositide 3-kinase (PI3K)gamma (PI3Kgamma(-/-)) in mice increases cardiac contractility by elevating intracellular cAMP and enhancing sarcoplasmic reticulum Ca(2+) handling. Because cAMP is a critical determinant of heart rate, we investigated whether heart rate is altered in mice lacking...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.107.158428
更新日期:2007-12-07 00:00:00
abstract:RATIONALE:Higher social integration is associated with lower cardiovascular mortality; however, whether it is associated with incident coronary heart disease (CHD), especially in women, and whether associations differ by case fatality are unclear. OBJECTIVES:This study sought to examine the associations between social...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.116.309443
更新日期:2017-06-09 00:00:00
abstract::An improved assay was used to investigate the effects of hypoxia or ischemia on interstitial fluid and coronary venous effluent levels of adenosine in isolated perfused nonworking rat hearts. The adenosine in 5- to 10-microliter samples of left ventricular epicardial surface transudates and coronary effluents was reac...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.60.2.177
更新日期:1987-02-01 00:00:00
abstract::To gain some insight into inotropic mechanisms, we compared the effects of several classes of inotropic interventions on the isometric twitch and force-velocity properties of isolated rabbit myocardium. Postextrasystolic potentiation was chosen as one of the interventions in the belief that its onset is so rapid that ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.65.5.1161
更新日期:1989-11-01 00:00:00
abstract::The effects of prostaglandin E2 (PGE2) indomethacin, and reserpine were evaluated in the rabbit renal vascular bed in situ under conditions of controlled blood flow. Intrarenal infusion of PGE2, 0.03 and 0.3 microgram/min, decreased responses to renal nerve stimulation, intra-arterial norepinephrine, and angiotensin. ...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.41.2.172
更新日期:1977-08-01 00:00:00
abstract:RATIONALE:Senescence of pulmonary artery smooth muscle cells (PA-SMCs) caused by telomere shortening or oxidative stress may contribute to pulmonary hypertension associated with chronic lung diseases. OBJECTIVE:To investigate whether cell senescence contributes to pulmonary vessel remodeling and pulmonary hypertension...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.111.241299
更新日期:2011-08-19 00:00:00
abstract::The transcription factor nuclear factor-kappaB (NF-kappaB) plays a pivotal role in the coordinated transactivation of cytokine and adhesion molecule genes involved in endothelial activation. Although recent reports have documented the contribution of NF-kappaB to apoptosis, it is still controversial. Especially, the r...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.86.9.974
更新日期:2000-05-12 00:00:00
abstract::Whole-cell voltage-clamp experiments and single-channel current recordings in cell-attached patch mode were performed on enzymatically dissociated single ventricular myocytes harvested from feline endocardial and epicardial surfaces. The studies were designed to compare the characteristics of inward rectifier K+ curre...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.70.1.91
更新日期:1992-01-01 00:00:00
abstract::The signaling pathways involved in the long-term metabolic effects of angiotensin II (Ang II) in vascular smooth muscle cells are incompletely understood but include the generation of molecules likely to affect oxidase activity. We examined the ability of Ang II to stimulate superoxide anion formation and investigated...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.74.6.1141
更新日期:1994-06-01 00:00:00
abstract::Membrane current abnormalities have been described in human heart failure. To determine whether similar current changes are observed in a large animal model of heart failure, we studied dogs with pacing-induced cardiomyopathy. Myocytes isolated from the midmyocardium of 13 dogs with heart failure induced by 3 to 4 wee...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.78.2.262
更新日期:1996-02-01 00:00:00
abstract::Vascular disease often involves vessel hypertrophy with underlying cellular hypertrophy or hyperplasia. Experimental diabetes stimulates hypertrophy of the rat mesenteric vasculature, and we investigated the hypothesis that this hypertrophy is associated with activation of Na(+)-H(+) exchange (NHE) activity. We measur...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.87.12.1133
更新日期:2000-12-08 00:00:00
abstract::The mTOR (mechanistic target of rapamycin) is a master regulator of several crucial cellular processes, including protein synthesis, cellular growth, proliferation, autophagy, lysosomal function, and cell metabolism. mTOR interacts with specific adaptor proteins to form 2 multiprotein complexes, called mTORC1 (mTOR co...
journal_title:Circulation research
pub_type: 杂志文章,评审
doi:10.1161/CIRCRESAHA.117.311147
更新日期:2018-02-02 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::A distal transcriptional enhancer has been previously reported upstream of the mouse renin gene. A homologous sequence is also present upstream of the human renin gene, but the mouse and human renin enhancers differ markedly in their ability to activate transcription of a renin promoter. Although the 2 enhancers share...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.85.6.479
更新日期:1999-09-17 00:00:00
abstract::alpha-Adrenergic receptor stimulation regulates the activity of a number of different cardiac ion channels, including those underlying one or more distinct Cl- conductances. The whole-cell patch-clamp technique was used in the present study to investigate the effects of alpha-adrenergic stimulation on the beta-adrener...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.78.6.1090
更新日期:1996-06-01 00:00:00
abstract:RATIONALE:Mitochondria, although required for cellular ATP production, are also known to have other important functions that may include modulating cellular responses to environmental stimuli. However, the mechanisms whereby mitochondria impact cellular phenotype are not yet clear. OBJECTIVE:To determine how mitochond...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.113.301319
更新日期:2013-09-13 00:00:00
abstract::Net cellular L-lactate efflux associated with accelerated anaerobic glycolysis has been implicated as a potential cause of the marked cellular K+ loss contributing to lethal cardiac arrhythmias in ischemic heart and to impaired function of fatigued skeletal muscle. To examine the mechanisms of transsarcolemmal L-lacta...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.74.5.829
更新日期:1994-05-01 00:00:00
abstract::The expression of angiotensin II type 2 (AT(2)) receptor is closely associated with cell growth, differentiation, and/or injury. We examined the effect of interferon (IFN)-gamma on AT(2) receptor expression in mouse fibroblast R3T3 cells and demonstrated that IFN-gamma treatment increased the expression of AT(2) recep...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.86.2.233
更新日期:2000-02-04 00:00:00
abstract::The cardiac muscarinic potassium channel (IK.ACh) is activated by a G protein upon receptor stimulation with acetylcholine. The G protein subunit responsible for activation (G alpha versus G beta gamma) has been disputed. We used G beta gamma inhibitors derived from the beta-adrenergic kinase 1 (beta ARK1) to assess t...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.76.5.832
更新日期:1995-05-01 00:00:00
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:BACKGROUND:Myocyte contractile dysfunction occurs in pathological remodeling in association with abnormalities in calcium regulation. Mice with cardiac myocyte-specific overexpression of Galphaq develop progressive left ventricular failure associated with myocyte contractile dysfunction and calcium dysregulation. OBJE...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/CIRCRESAHA.110.217570
更新日期:2010-07-23 00:00:00
abstract::The purpose of this study was to determine whether a cyclic adenosine 3',5'-monophosphate-dependent process can be involved in the regulation of vascular smooth muscle alpha 1-adrenergic receptor responsiveness. Experiments were performed in cultured rabbit aortic smooth muscle cells which were characterized previousl...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.res.58.2.292
更新日期:1986-02-01 00:00:00
abstract::Mutations in the human gene encoding the nucleotide-binding region in the gamma-subunit of AMP-activated protein kinase (AMPK) cause cardiomyopathy with preexcitation syndrome. Mutant AMPK showed reduced binding affinity to nucleotides in vitro raising the possibility that altered regulation of AMPK activity by AMP/AT...
journal_title:Circulation research
pub_type: 杂志文章
doi:10.1161/01.RES.0000179035.20319.c2
更新日期:2005-08-19 00:00:00