OXIDANT-INDUCED MECHANISM OF PLASMA MEMBRANE PHOSPHOLIPASE A1 ACTIVATION IN PULMONARY ARTERY ENDOTHELIAL CELLS

1991 ◽  
pp. 577-581
Author(s):  
Jawaharlal M. Patel ◽  
K. Madhavi Sekharam ◽  
Edward R. Block
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Pulmonary Artery ◽  
Phospholipase A1

Serotonin transport and fluidity in plasma membrane vesicles: effect of hyperoxia

1988 ◽  
Vol 254 (6) ◽  
pp. C781-C787 ◽  
Author(s):  
N. P. Sheridan ◽  
E. R. Block
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Pulmonary Artery ◽  
Membrane Fluidity ◽  
Fluorescence Probe ◽  
Membrane Vesicles ◽  
Phase System ◽  
Maximal Velocity ◽  
Plasma Membrane Vesicles ◽  
Plasma Membrane Fluidity

Plasma membrane vesicles were prepared from porcine pulmonary artery endothelial cells by a dextran-polyethylene glycol two-phase system. Specific carrier-mediated transport of 5-hydroxytryptamine (5-HT) into the vesicles was examined. Transport required a Na+ gradient (out greater than in) across the membrane, and accumulated 5-HT rapidly effluxed out of the vesicles when the ionophore gramicidin was added. Transport was inhibited by the antidepressant imipramine. 5-HT transport into plasma membrane vesicles appeared saturable and exhibited Michaelis-Menten kinetics (Km 7.4 microM, maximal velocity 217 pmol.min-1.mg membrane protein-1). A 24-h exposure to 95% O2 at 1 atmosphere absolute resulted in a 21% decrease (P less than 0.05) in specific 5-HT transport by plasma membrane vesicles. Hyperoxia also caused a significant (P less than 0.01) decrease in plasma membrane fluidity, as measured with the fluorescence probe 1,6-diphenyl-1,3,5-hexatriene. These results indicate that pulmonary artery endothelial cell plasma membrane vesicles provide a good model for studying 5-HT transport activity in vitro. Hyperoxia affects plasma membrane fluidity and 5-HT transport in pulmonary artery endothelial cells, suggesting a possible cause-and-effect relationship between the two.

scholarly journals Oxidized glutathione decreases luminal Ca2+ content of the endothelial cell ins(1,4,5)P3-sensitive Ca2+ store

1995 ◽  
Vol 312 (2) ◽  
pp. 485-489 ◽  
Author(s):  
P N Henschke ◽  
S J Elliott
Keyword(s):  
Signal Transduction ◽  
Endothelial Cells ◽  
Plasma Membrane ◽  
Endothelial Cell ◽  
Pulmonary Artery ◽  
Vascular Tissue ◽  
Oxidant Stress ◽  
Inhibitory Effect ◽  
Oxidized Glutathione ◽  
Intact Cells

The model oxidant, t-butyl hydroperoxide (t-buOOH), inhibits Ins(1,4,5)P3-dependent Ca2+ signalling in calf pulmonary artery endothelial cells. Metabolism of t-buOOH within the cytosol is coupled to the oxidation of glutathione. In this study, we investigated whether oxidized glutathione (GSSG) is the intracellular moiety responsible for mediating the effects of t-buOOH on Ca2+ signalling. The increase in cytosolic [Ca2+] stimulated by application of 2,5-di-t-butylhydroquinone (BHQ) was used to estimate the luminal Ca2+ content of the Ins(1,4,5)P3-sensitive store in intact cells. Luminal Ca2+ content was unaffected by t-buOOH (0.4 mM, 0-3 h) unless intracellular GSSG content was concomitantly elevated. The effect was specific for increased GSSG and was not replicated by depletion of GSH. These results suggest that cytosolic GSSG, produced endogenously within the endothelial cell, decreases the luminal Ca2+ content of Ins(1,4,5)P3-sensitive Ca2+ stores. Depletion of internal Ca2+ stores by GSSG may represent a key mechanism by which some forms of oxidant stress inhibit signal transduction in vascular tissue. At the plasma membrane, t-buOOH is known to inhibit the capacitative Ca2+ influx pathway. Increased intracellular GSSG potentiated the inhibitory effect of t-buOOH on Ca2+ influx, thereby providing the first evidence that activity of the capacitative Ca2+ influx channel is sensitive to thiol reagents formed endogenously within the cell.

scholarly journals BS44 Cytokine induced downregulation of plasma membrane calcium atpase 4 gene increases sensitivity to apoptosis in pulmonary artery endothelial cells

2019 ◽  
Author(s):  
Jude Ihugba ◽  
Satishkumar Kurusamy ◽  
Reshma Naomi Ranjit Immanuel ◽  
Kinza Khan ◽  
Jayashree Jayachandran ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Pulmonary Artery ◽  
Calcium Atpase ◽  
Plasma Membrane Calcium Atpase

Overexpression of Plasma Membrane Annexin II In NO2-Exposed Pulmonary Artery Endothelial Cells

1997 ◽  
Vol 23 (1) ◽  
pp. 120-126 ◽  
Author(s):  
Yong D Li ◽  
Jawaharlal M Patel ◽  
Jianliang Zhang ◽  
Edward R Block
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Pulmonary Artery ◽  
Annexin Ii

scholarly journals Cavin-1 regulates BMP/Smad signaling through the interaction of Caveolin-1 with BMPRII in pulmonary artery endothelial cells

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Tomita ◽  
N Nakanishi ◽  
T Ogata ◽  
Y Tsuji ◽  
A Sakamoto ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Endothelial Cells ◽  
Plasma Membrane ◽  
Pulmonary Artery ◽  
Signaling Pathway ◽  
Knockout Mice ◽  
Bmp Signaling ◽  
Smad Signaling ◽  
Caveolin 1 ◽  
Smad Signaling Pathway

Abstract Background Pulmonary hypertension (PH) is a progressive disease associated with poor outcome. Caveolin-1 (Cav1) is a component of caveolae and classified as a related gene of pulmonary arterial hypertension (PAH). Gene mutations of bone morphogenetic protein type II receptor (BMPRII) is a most common cause of PAH. BMPRII is localized in caveolae and associates with Cav1. However, the role of the Caveolin-Cavin system on the BMP/Smad signaling and the PAH progression has not been well-known. Purpose The aim of our study is to investigate the relationship between Caveolin-Cavin system and BMP/Smad signaling pathway and explore the mechanism of downstream signal transduction of BMP signaling by the interaction between Caveolin and BMPRII. Methods Cav1 knockout mice were used to assess PH and caveolae in pulmonary artery endothelial cells were observed by electron microscope. Cav1 and Cavin-1, which is a component of caveolae and form a complex with Cav1, were knocked-down in human pulmonary artery endothelial cell (hPAEC) using siRNA and phosphorylation of Smad signal was evaluated. Apoptosis of these cells was explored by flow cytometry. We investigated the interaction between Cav1 and BMPRII, and evaluated whether Cavin-1 affects this interaction and signal transduction of BMP signaling. Results As previously described, deletion of Cav1 revealed disappearance of caveolae in pulmonary artery endothelial cells (PAECs), and Cav1 knockout mice exhibited PH with pulmonary vascular remodeling and right ventricular hypertrophy. We then examined roles of Cav1 in human PAECs (hPAECs). Cav1 knockdown in hPAECs reduced phosphorylation of Smad 1/5/9. In addition, Cav1 knockdown significantly increased hypoxia-induced apoptosis in hPAEC. Knockdown of Cavin-1 reversed phosphorylation of Smad 1/5/9 decreased by Cav1 knockdown in BMP9 stimulation. Cavin-1 reversed the expression of BMPRII decreased by overexpression of Cav1. Cav1 was associated with Cavin-1 at the plasma membrane in PAECs. Cav1 also associated with BMPRII at the membrane of hPAECs that was inhibited by Cavin-1, and Cavin-1 reduced the localization of BMPRII to the membrane of hPAECs. These results suggest that BMPRII interacts with Cav1 via Cavin-1-associated localization at the plasma membrane in hPAECs, resulting in regulating BMP/Smad signaling pathway and involving in the development of PAH. Conclusions Cavin-1 affects the interaction of Cav1 with BMPRII at the membrane of PAECs, and regulates BMP/Smad signaling. These results reveal a previously undescribed function of Cavin-Caveolin system in the development of PAH through regulation of BMP/Smad signaling. Funding Acknowledgement Type of funding source: None

Localization of carbonic anhydrase on pulmonary artery endothelial cells in culture

1982 ◽  
Vol 53 (4) ◽  
pp. 914-919 ◽  
Author(s):  
U. S. Ryan ◽  
P. L. Whitney ◽  
J. W. Ryan
Keyword(s):  
Endothelial Cells ◽  
Plasma Membrane ◽  
Carbonic Anhydrase ◽  
Pulmonary Artery ◽  
Venous Blood ◽  
Carbonic Anhydrase Activity ◽  
Intact Cells ◽  
Cells In Culture ◽  
Carbonic Anhydrase B ◽  
Arterial Blood

Bovine pulmonary artery endothelial cells in culture possess carbonic anhydrase activity and immunoreactivity. The intact cells and cell homogenates lower the pH of 25 mM triethanolamine sulfate buffer saturated with CO2 (starting pH 8.1). The intact cells are more reactive than the cell homogenates, and the enzymic activity is enriched in association with the plasma membrane fraction. Specific immunofluorescence is obtained when the cells are incubated with rabbit antibovine erythrocyte carbonic anhydrase B and then with goat antirabbit immunoglobulin G coupled to fluorescein. At the level of electron microscopy, antibodies to carbonic anhydrase B are reactive with sites along the plasma membrane and associated caveolae. Multivesicular bodies are the only intracellular sites labeled and appear to correspond to the globular sites of intracellular immunofluorescence. Cells maintained and propagated in culture in the absence of an exogenous source of carbonic anhydrase nonetheless possess carbonic anhydrase activity, suggesting that the cells are capable of synthesizing the enzyme. Taken together, our results indicate that pulmonary artery endothelial cells possess carbonic anhydrase situated so that the enzyme could readily catalyze the dehydration of plasma HCO-3 to facilitate CO2 excretion and participate in the regulation of blood pH as central venous blood is converted into systemic arterial blood.

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