scholarly journals Expression of organic cation transporter 3 (SLC22A3) and plasma membrane monoamine transporter (SLC29A4) in human umbilical vein endothelial cells and their relevance for histamine uptake

2012 ◽  
Vol 13 (Suppl 1) ◽  
pp. A73
Author(s):  
Polonca Ferk ◽  
Metoda Lipnik-Štangelj ◽  
Mojca Kržan ◽  
Katarina Černe
1988 ◽  
Vol 255 (1) ◽  
pp. 179-184 ◽  
Author(s):  
T J Hallam ◽  
R Jacob ◽  
J E Merritt

Human umbilical-vein endothelial cells stimulated with thrombin or histamine show an increase in [Ca2+]i (cytoplasmic free calcium concn.) that is maintained well above the basal pre-stimulated value as long as agonist and a source of extracellular Ca2+ are present. These results provide circumstantial evidence that agonists stimulate influx of Ca2+ across the plasma membrane and into the cytoplasm. Here, we have used Mn2+ as the extracellular bivalent cation which can bind to the fluorescent Ca2+ indicator fura-2 to quench its fluorescence completely. Human umbilical-vein endothelial cells were loaded with fura-2 and, in the presence of extracellular Mn2+, thrombin and histamine were shown to cause quenching of the intracellular dye. This result demonstrates conclusively that agonists can stimulate the influx of bivalent cations. Stimulated discharge of Ca2+ from intracellular stores and influx of Mn2+ were temporally resolved in the same cells to show that release of Ca2+ from intracellular stores clearly precedes influx. Influx of Mn2+ was also demonstrated when extracellular Mn2+ was added after agonist at a time when [Ca2+]i had fallen back to the basal value, showing that influx is not dependent on elevated [Ca2+]i.


2021 ◽  
Vol 22 (24) ◽  
pp. 13420
Author(s):  
Nikki J. Clauss ◽  
Wouter Koek ◽  
Lynette C. Daws

A lack of effective treatment and sex-based disparities in psychostimulant addiction and overdose warrant further investigation into mechanisms underlying the abuse-related effects of amphetamine-like stimulants. Uptake-2 transporters such as organic cation transporter 3 (OCT3) and plasma membrane monoamine transporter (PMAT), lesser studied potential targets for the actions of stimulant drugs, are known to play a role in monoaminergic neurotransmission. Our goal was to examine the roles of OCT3 and PMAT in mediating amphetamine (1 mg/kg)-induced conditioned place preference (CPP) and sensitization to its locomotor stimulant effects, in males and females, using pharmacological, decynium-22 (D22; 0.1 mg/kg, a blocker of OCT3 and PMAT) and genetic (constitutive OCT3 and PMAT knockout (−/−) mice) approaches. Our results show that OCT3 is necessary for the development of CPP to amphetamine in males, whereas in females, PMAT is necessary for the ability of D22 to prevent the development of CPP to amphetamine. Both OCT3 and PMAT appear to be important for development of sensitization to the locomotor stimulant effect of amphetamine in females, and PMAT in males. Taken together, these findings support an important, sex-dependent role of OCT3 and PMAT in the rewarding and locomotor stimulant effects of amphetamine.


1990 ◽  
Vol 63 (02) ◽  
pp. 298-302 ◽  
Author(s):  
Kiyoshi Andoh ◽  
Kjell Sverre Pettersen ◽  
Christiane Filion -Myklebust ◽  
Hans Prydz

SummaryHuman umbilical vein endothelial cells (HUVEC) are inducible for tissue factor (TF) activity in culture. Based on experiments using ECGF (4–20 µg/ml) with heparin (90 µg/ml), we obtained the followingresults: 1) In confluent HUVEC cultures, ECGF had essentially no influence on the levels of inducible TF. 2) In growing HUVEC cultures, ECGF reduced the TF response shortly after seeding but full response was regained when cells were kept confluent for 2–3 days. 3) Although secondary cultures responded best to TF induction in the absence of ECGF, the response was essentially equal over at least 8 passages in the prcgcncc of ECGF 1) Of total cellular TF induced in HUVEC, about 25% was available on the surface, and less than 4% was released with theshed plasma membrane vesicles. The proportion of total TF a>ctivity available on the surface of mtact cells wasnot influenced by the presence of ECGF 5) T½, for the decay of TF activity induced was 8.3—9.5 h, whereas in HUVEC when protein synthesis was blocked afterIF induction a T½ of about 30 h was found.


1994 ◽  
Vol 301 (3) ◽  
pp. 683-691 ◽  
Author(s):  
S Horie ◽  
H Ishii ◽  
H Hara ◽  
M Kazama

The effects of phospholipid vesicles and their fatty acid compositions on the acceleration of Protein C activation by thrombin-thrombomodulin was studied in vitro. Four main phospholipid fractions were prepared from cultured human umbilical vein endothelial cells, and purified thrombomodulin from human placenta was reconstituted into vesicles consisting of phosphatidylcholine (PtdCho) alone, PtdCho plus phosphatidylethanolamine (PtdEtn), PtdCho plus phosphatidylserine (PtdSer) and PtdCho plus PtdIns (1:1, w/w in each case). Vesicles of PtdCho, PtdIns/PtdCho, PtdSer/PtdCho and PtdEtn/PtdCho increased thrombin-thrombomodulin-catalysed protein C activation by 1.2-, 1.9-, 4.3- and 8.4-fold respectively compared with that in the absence of phospholipid. This Protein C activation was not affected by distearoyl PtdEtn/distearoyl PtdCho, whereas it was markedly increased with increasing content of unsaturated fatty acid in PtdEtn. The thrombin-dependent Protein C activation by thrombomodulin reconstituted into dilinolenoyl PtdEtn/distearoyl PtdCho was 14.6 times that by thrombomodulin reconstituted into distearoyl PtdEtn/distearoyl PtdCho, as a result of a decrease in the dissociation constant (Kd) for thrombin and the Michaelis constant (Km) for Protein C of thrombomodulin. Binding of Protein C to PtdEtn/PtdCho fixed to a microwell plate required the presence of CaCl2 and increased with increasing degree of unsaturation of fatty acid in PtdEtn. As PtdEtn appeared on the outside of the plasma membrane in cultured human umbilical vein endothelial cells after thrombin stimulation, it was presumed that Protein C activation could be elevated by PtdEtn at the outer surface of the plasma membrane via an increased affinity between thrombomodulin, thrombin and Protein C, resulting from both increased formation of the thrombin-thrombomodulin complex via a conformational change in thrombomodulin and increased binding of Protein C to the membrane phospholipid in a Ca(2+)-dependent manner.


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