Flow cytometric studies of nucleoside transport regulation in single chromaffin cells

@article{Sen1998FlowCS,
  title={Flow cytometric studies of nucleoside transport regulation in single chromaffin cells},
  author={Raquel P. Sen and Esmerilda G Delicado and Alberto M. {\'A}lvarez and A M Brocklebank and James S. Wiley and Mar{\'i}a-Teresa Miras-Portugal},
  journal={FEBS Letters},
  year={1998},
  volume={422}
}
The present paper reveals that a fluorescent derivative of nitrobenzylthioinosine, 5‐(SAENTA‐x8)‐fluorescein, is a highly specific inhibitor of the neural NBTI‐sensitive nucleoside transporter. 5‐(SAENTA‐x8)‐fluorescein inhibited adenosine transport and [3H]NBTI binding with a K i of 4 nM in cultured chromaffin cells. Flow cytometry demonstrated that 5‐(SAENTA‐x8)‐fluorescein specifically interacted with the NBTI‐sensitive nucleoside transporters with high affinity (K D=6 nM). Activation of… Expand
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References

SHOWING 1-10 OF 22 REFERENCES
Flow cytometric quantitation of nucleoside transporter sites on human leukemic cells.
TLDR
The improved properties of 5-(SAENTA-x8)-fluorescein over those of its prototype molecule make it a suitable reagent for flow cytometric quantitation of nucleoside transporter expression on leukemic cells isolated from patient samples. Expand
Down-regulation and recycling of the nitrobenzylthioinosine-sensitive nucleoside transporter in cultured chromaffin cells.
TLDR
The dynamics of the nitrobenzylthioinosine (NBTI)-sensitive nucleoside transporter were studied in cultured chromaffin cells and a similar pattern of internalization and reappearance of nucleosid transporters was observed in cells cross-linked with non-labelled NBTI. Expand
Adenosine transporters in chromaffin cells: subcellular distribution and characterization.
Adenosine transporters in freshly isolated and cultured chromaffin cells were quantified by the [3H]dipyridamole binding technique, showing a maximal bound capacity of 0.4 +/- 0.05 pmol/10(6) cellsExpand
A new fluorescent probe for the equilibrative inhibitor-sensitive nucleoside transporter. 5'-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5'-thioadenosine (SAENTA)-chi 2-fluorescein.
TLDR
SAENTA-chi 2-fluorescein is a high-affinity ligand for the equilibrative inhibitor-sensitive nucleoside transporter which allows rapid assessment of transport capacity by flow cytometry. Expand
Effects of phorbol esters and secretagogues on nitrobenzylthioinosine binding to nucleoside transporters and nucleoside uptake in cultured chromaffin cells.
TLDR
Protein kinase C from bovine brain in the presence of ATP and effectors, decreased the number of high-affinity NBTI-binding sites in purified chromaffin cell plasma membranes, suggesting the possibility of a molecular modification at the transporter level. Expand
[3H]Nitrobenzylthioinosine Binding as a Probe for the Study of Adenosine Uptake Sites in Brain
TLDR
[3H]NBI binding in brain should provide a useful probe for the study of adenosine transport in the brain, since thiopurines were very potent inhibitors of binding whereasAdenosine receptor ligands, such as cyclohexyladenosine and 2‐chloroadenosine were three to four orders of magnitude less potent. Expand
Effect of forskolin and cyclic AMP analog on adenosine transport in cultured chromaffin cells
TLDR
The adenosine transport in cultured chromaffin cells was inhibited by the presence of the adenylate cyclase activator, forskolin, and a cAMP analog, suggesting that this inhibition could be mediated by a molecular modification ofAdenosine transporters, the binding with NBTI is therefore a possible parameter of this modification. Expand
Incorporation of adenosine into nucleotides of chromaffin cells maintained in primary cultures
TLDR
In intact chromaffin tissue, a very low incorporation was found, but later on, and in the presence of nerve growth factor (NGF), a time dependent increase of adenosine incorporation was observed which, in 84-h old cells reached up to 54 times more than that found in intact tissue, probably in relation to granule maturation. Expand
Heterogeneity of [3H]Dipyridamole Binding to CNS Membranes: Correlation with [3H]Nitrobenzylthioinosine Binding and [3H]Uridine Influx Studies
TLDR
The nitrobenzylthioinosine‐resistant [3H]dipyridamole binding sites were relatively insensitive to inhibition by all of the nucleoside transport substrates and inhibitors tested, with the exception of dipyridAMole itself. Expand
[3H]Dipyridamole Binding to Guinea Pig Brain Membranes: Possible Heterogeneity of Central Adenosine Uptake Sites
TLDR
The data are consistent with [3H]DPR being a useful additional ligand for the adenosine uptake site and provide evidence that multiple uptake binding sites exist of which only about 40% are NBI‐sensitive. Expand
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