Linked Life Data

6203540

Source:http://linkedlifedata.com/resource/pubmed/id/6203540

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1984-7-2
pubmed:abstractText
Theophylline, caffeine, isobutylmethylxanthine, papaverine, N6-cyclohexyladenosine, N6-allyl-N6-cyclohexyladenosine ( ACHA ) and N6-L-phenylisopropyladenosine (L-PIA) inhibited the transport of adenosine, uridine and hypoxanthine in Novikoff rat hepatoma cells. The IC50 values for the inhibition of uridine transport ranged from 5 microM for ACHA to 3200 microM for caffeine and were inversely proportional to the lipid solubility of the inhibitors. L-PIA and papaverine inhibited uridine influx in a non-competitive manner, having a greater influence on the Michaelis-Menten constant than on maximum velocity, just as observed previously for the inhibition of nucleoside transport by dipyridamole and hypoxanthine. [3H]L-PIA rapidly accumulated in Novikoff cells at 25 degrees to about five times higher levels than present extracellularly. The initial rates of L-PIA uptake were directly proportional to its extracellular concentration between 0.01 and 240 microM and not affected by structurally related analogs, methylxanthines, papaverine, dipyridamole, or 2 mM uridine, but were dependent on temperature. We conclude that L-PIA inhibits nucleoside transport in these cells without being significantly transported by the carrier, that it equilibrates rapidly across the plasma membrane without carrier mediation consistent with its lipophilicity, and that it accumulates concentratively in cells due to partitioning into membrane lipids and binding to intracellular components.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2952
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1783-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Inhibition of the transport of adenosine, other nucleosides and hypoxanthine in novikoff rat hepatoma cells by methylxanthines, papaverine, N6-cyclohexyladenosine and N6-phenylisopropyladenosine.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.