Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1996-8-23
pubmed:abstractText
Tritiated methylphenylpyridinium ([3H]MPP+), a substrate of the neuronal and extraneuronal noradrenaline transporter (uptake1 and uptake2, respectively) and of the organic cation transporter (OCT1), was used to characterize the amine transport system of the established human glioma cell line SK-MG-1. Uptake of [3H]MPP+ (25 nM) into SK-MG-1 cells increased linearly with time for up to 15 min. Selective uptake1 inhibitors (e.g. (+)oxaprotiline) or omission of Na+ or Cl-ions did not affect [3H]MPP+ uptake, whereas uptake2 inhibitors such as O-methyl-isoprenaline (OMI) or corticosterone as well as depolarizing concentrations of K+ or Ba2+ strongly reduced [3H]MPP+ uptake. Initial rates of OMI(100 microM)-sensitive [3H]MPP+ uptake were saturable, with a K(m) of about 17 microM and a maximal rate of about 50 pmol/(min x mg protein). IC50 (or Ki) values for inhibition of [3H]MPP+ uptake by substrates and inhibitors of uptake2 or OCT1 were highly significantly correlated with published IC50 values for inhibition of uptake2 but not with corresponding values for inhibition of OCT1. The results presented here clearly demonstrate that human glioma cells express an uptake2 transporter. Thus, glial cells in the human central nervous system endowed with this transporter are likely to contribute to the inactivation of neuronally released noradrenaline.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
353
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
328-33
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Expression of the extraneuronal monoamine transporter (uptake2) in human glioma cells.
pubmed:affiliation
Institut für Pharmakologie und Toxikologie, Universität Bonn, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't