Effects of endothelin-1 on release of adrenomedullin and C-type natriuretic peptide from individual human vascular endothelial cells

Regulation of cardiovascular system activity involves complex interactions amongst numerous factors. Three of these vasoactive factors are adrenomedullin, C-type natriuretic peptide (CNP) and endothelin-1 (ET-1), each of which is claimed to have important local effects. To investigate paracrine/autocrine regulation of the secretion of these peptides we used a cell immunoblot method. We postulated that basal release of adrenomedullin and CNP by endothelial cells is modulated by ET-1. Dispersed human aortic endothelial cells were attached to a protein binding membrane and incubated for 1 or 4 h with control medium or with ET-1, endothelin receptor antagonists or antibody to ET-1, and then submitted to immunohistochemical staining. Peptides (adrenomedullin, CNP and ET-1) within individual cells were stained, as was peptide secreted and adjacent to the cell. It was demonstrated that adrenomedullin, CNP and ET-1 can be contained within the same cell. In addition, we observed that individual endothelial cells can secrete all three peptides. The endothelin ET-A/ET-B receptor antagonist, bosentan, the ET-B receptor antagonist, BQ-788, and anti-ET-1 serum decreased the percentage of endothelial cells that secreted adrenomedullin and CNP relative to control. Conversely, the addition of ET-1 induced an increase in the number of endothelial cells that secreted adrenomedullin and CNP. These results provide strong evidence that endogenous ET-1, from human vascular endothelial cells, acts in a paracrine/autocrine manner to modulate the basal release of adrenomedullin and CNP. Our observations of this modulation suggest that vascular endothelial cells of humans constitute an important component of a self-responsive vasoregulatory system.

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Modulation of calcium homeostasis in cultured rat aortic endothelial cells by intracellular acidification

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1993.265.4.h1424 ◽

1993 ◽

Vol 265 (4) ◽

pp. H1424-H1433 ◽

Cited By ~ 2

Author(s):

R. C. Ziegelstein ◽

L. Cheng ◽

P. S. Blank ◽

H. A. Spurgeon ◽

E. G. Lakatta ◽

...

Keyword(s):

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Cytosolic Calcium ◽

Ph Sensitive ◽

Vascular Endothelial ◽

Intracellular Acidification ◽

Cytosolic Ph ◽

Aortic Endothelial Cells ◽

Endothelial Monolayers ◽

Aortic Endothelial

Acidosis produces vasodilation in a process that may involve the vascular endothelium. Because synthesis and release of endothelium-derived vasodilatory substances are linked to an increase in cytosolic calcium concentration ([Ca2+]i), we examined the effect of intracellular acidification on cultured rat aortic endothelial cells loaded either with the pH-sensitive probe carboxy-seminaphthorhodafluor-1 or the Ca(2+)-sensitive fluorescent probe indo 1. The basal cytosolic pH (pHi) of endothelial monolayers in a 5% CO2-HCO3- buffer was 7.27 +/- 0.02 and that in a bicarbonate-free solution was 7.22 +/- 0.03. Acidification was induced either by removal of NH4Cl (delta pHi = -0.10 +/- 0.02), changing from a bicarbonate-free to a 5% CO2-HCO3(-)-buffered solution at constant buffer pH (delta pHi = -0.18 +/- 0.03), or changing from a 5% to a 20% CO2-HCO3- solution (delta pHi = -0.27 +/- 0.07). Regardless of the method used, intracellular acidification increased [Ca2+]i as indexed by indo 1 fluorescence. The increase in [Ca2+]i induced by changing from a 5 to a 20% CO2-HCO3- solution was not significantly altered by removal of buffer Ca2+ either before or after depletion of bradykinin- and thapsigargin-sensitive intracellular Ca2+ stores. Thus intracellular acidification of vascular endothelial cells releases Ca2+ into the cytosol either from pH-sensitive intracellular buffer sites, mitochondria, or from bradykinin- and thapsigargin-insensitive intracellular stores. This Ca2+ mobilization may be linked to endothelial synthesis and release of vasodilatory substances during acidosis.

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Human serum stimulates endothelin-1 synthesis more potently than prostacyclin production by cultured vascular endothelial cells

Life Sciences ◽

10.1016/0024-3205(91)90259-e ◽

1991 ◽

Vol 49 (8) ◽

pp. 603-609 ◽

Cited By ~ 6

Author(s):

Ari Ristimäki ◽

Risto Renkonen ◽

Outi Saijonmaa ◽

Olavi Ylikorkala ◽

Lasse Viinikka

Keyword(s):

Endothelial Cells ◽

Human Serum ◽

Vascular Endothelial Cells ◽

Vascular Endothelial ◽

Endothelin 1 ◽

Prostacyclin Production

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Intracellular pathways of insulin transport across vascular endothelial cells

AJP Cell Physiology ◽

10.1152/ajpcell.1988.255.4.c459 ◽

1988 ◽

Vol 255 (4) ◽

pp. C459-C464 ◽

Cited By ~ 35

Author(s):

H. L. Hachiya ◽

P. A. Halban ◽

G. L. King

Keyword(s):

Endothelial Cells ◽

Insulin Receptor ◽

Vascular Endothelial Cells ◽

Insulin Degradation ◽

Vascular Endothelial ◽

Aortic Endothelial Cells ◽

Lysosomal Protease ◽

Insulin Transport ◽

Bovine Aortic Endothelial Cells ◽

Aortic Endothelial

Processing and transport of hormones across vascular endothelial cells may modulate hormone action at subendothelial tissue sites. Insulin was transported across cultured rat capillary and bovine aortic endothelial cells, after a delay of 5-10 min, at a constant rate for 60 min at 37 degrees C. 125I-labeled insulin transport was inhibited by 88 +/- 11% (SE, n = 4) and 75 +/- 18% (SE, n = 4) in the presence of anti-insulin receptor antibody and unlabeled insulin (at 10(-7) M), respectively. Reverse phase high-performance liquid chromatography showed 88% of the 125I-insulin transported over 60 min was indistinguishable from the 125I-insulin added to the cells at 4 degrees C. In aortic endothelial cells preincubated with 2.3 x 10(-9) M of insulin for 24 h, insulin receptor binding was downregulated by 67%, and 125I-insulin transport was decreased by 52 +/- 11%. The proton ionophore monensin (0.05 mM) increased the internalized insulin in bovine aortic endothelial cells by 78%, with a corresponding decrease in 125I-insulin released by 76 +/- 2% (SE, n = 4). 125I-insulin transport across the aortic endothelial cell monolayer was similarly decreased (54 +/- 12%, SE, n = 4) by monensin. In contrast, the lysosomal protease inhibitor leupeptin had no effect. Degradation and transport were similarly dissociated by low temperature. At 15 degrees C, no significant insulin degradation was detected, whereas 125I-insulin release from the cells continued at 30 +/- 3% of the rate at 37 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

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Stereoselectivity of ectonucleotidases on vascular endothelial cells

Biochemical Journal ◽

10.1042/bj2140975 ◽

1983 ◽

Vol 214 (3) ◽

pp. 975-981 ◽

Cited By ~ 70

Author(s):

N J Cusack ◽

J D Pearson ◽

J L Gordon

Keyword(s):

Endothelial Cells ◽

Vascular Endothelial Cells ◽

Thiol Group ◽

Side Chain ◽

Vascular Endothelial ◽

Nucleotide Analogues ◽

Aortic Endothelial Cells ◽

Nucleotide Analogue ◽

High Degree ◽

Aortic Endothelial

We have investigated the stereoselectivity of ectonucleotidases (nucleoside triphosphatase, EC 3.6.1.15; nucleoside diphosphatase, EC 3.6.1.6; 5′-nucleotidase, EC 3.1.3.5) on pig aortic endothelial cells using two classes of nucleotide analogue. In experiments with nucleotide enantiomers in which the natural D-ribofuranosyl moiety is replaced by an L-ribofuranosyl moiety, the rate of catabolism of 100 microM-L-ATP was one-fifth that of D-ATP, the rate of catabolism of 100 microM-L-ADP was one-fifteenth that of D-ADP and there was no detectable catabolism of 100 microM-L-AMP. Each of the L-enantiomers inhibited, apparently competitively, the catabolism of the corresponding D-enantiomer; Ki values were approx. 0.6 mM, 1.0 mM and 3.9 mM for L-ATP, L-ADP and L-AMP respectively. Experiments with adenosine 5′-[beta, gamma-imido]triphosphate and with D- and L-enantiomers of adenosine 5′-[beta, gamma-methylene]triphosphate revealed modest ectopyrophosphatase activity, undetectable in experiments with natural nucleotides, which was also stereoselective. Use of phosphorothioate nucleotide analogues demonstrated that ATP catabolism was virtually stereospecific with respect to the geometry of the thiol group substituted on the beta-phosphate: the Rp isomer was degraded, whereas there was little or no breakdown of the Sp isomer. ADP catabolism was also stereospecific with respect to the geometry of the thiol group substituted on the alpha-phosphate: the Sp isomer but not the Rp isomer was degraded. The geometry of thiol-group substitution on the alpha-phosphate had no effect on ATP catabolism to ADP. There was no detectable catabolism of analogues with thiol-group substitution on the terminal phosphate. Each of the phosphorothioate analogues that was catabolized broke down at a rate similar to that of the natural nucleotide from which it was derived. These results demonstrate that the ectonucleotidases on pig aortic endothelial cells exhibit a high degree of stereoselectivity, characteristic for each enzyme, both with respect to the ribofuranosyl moiety and to the phosphate side chain.

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Lipoproteins Regulate C-Type Natriuretic Peptide Secretion From Cultured Vascular Endothelial Cells

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/01.atv.15.11.1968 ◽

1995 ◽

Vol 15 (11) ◽

pp. 1968-1974 ◽

Cited By ~ 21

Author(s):

Seigo Sugiyama ◽

Kiyotaka Kugiyama ◽

Toshiyuki Matsumura ◽

Shin-ichi Suga ◽

Hiroshi Itoh ◽

...

Keyword(s):

Endothelial Cells ◽

Natriuretic Peptide ◽

Vascular Endothelial Cells ◽

Vascular Endothelial ◽

Peptide Secretion

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Aerobic exercise training reduces plasma endothelin-1 concentration in older women

Journal of Applied Physiology ◽

10.1152/japplphysiol.01016.2002 ◽

2003 ◽

Vol 95 (1) ◽

pp. 336-341 ◽

Cited By ~ 111

Author(s):

Seiji Maeda ◽

Takumi Tanabe ◽

Takashi Miyauchi ◽

Takeshi Otsuki ◽

Jun Sugawara ◽

...

Keyword(s):

Endothelial Cells ◽

Exercise Training ◽

Aerobic Exercise ◽

Older Women ◽

Ventilatory Threshold ◽

Vascular Endothelial Cells ◽

Aerobic Exercise Training ◽

Vascular Endothelial ◽

Middle Aged ◽

Endothelin 1

Endothelial function deteriorates with aging. On the other hand, exercise training improves the function of vascular endothelial cells. Endothelin-1 (ET-1), which is produced by vascular endothelial cells, has potent constrictor and proliferative activity in vascular smooth muscle cells and, therefore, has been implicated in regulation of vascular tonus and progression of atherosclerosis. We previously reported significantly higher plasma ET-1 concentration in middle-aged than in young humans, and recently we showed that plasma ET-1 concentration was significantly decreased by aerobic exercise training in healthy young humans. We hypothesized that plasma ET-1 concentration increases with age, even in healthy adults, and that lifestyle modification (i.e., exercise) can reduce plasma ET-1 concentration in previously sedentary older adults. We measured plasma ET-1 concentration in healthy young women (21–28 yr old), healthy middle-aged women (31–47 yr old), and healthy older women (61–69 yr old). The plasma level of ET-1 significantly increased with aging (1.02 ± 0.08, 1.33 ± 0.11, and 2.90 ± 0.20 pg/ml in young, middle-aged, and older women, respectively). Thus plasma ET-1 concentration was markedly higher in healthy older women than in healthy young or middle-aged women (by ∼3- and 2-fold, respectively). In healthy older women, we also measured plasma ET-1 concentration after 3 mo of aerobic exercise (cycling on a leg ergometer at 80% of ventilatory threshold for 30 min, 5 days/wk). Regular exercise significantly decreased plasma ET-1 concentration in the healthy older women (2.22 ± 0.16 pg/ml, P < 0.01) and also significantly reduced their blood pressure. The present study suggests that regular aerobic-endurance exercise reduces plasma ET-1 concentration in older humans, and this reduction in plasma ET-1 concentration may have beneficial effects on the cardiovascular system (i.e., prevention of progression of hypertension and/or atherosclerosis by endogenous ET-1).

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