Linked Life Data

8166278

Source:http://linkedlifedata.com/resource/pubmed/id/8166278

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3 Pt 1
pubmed:dateCreated
1994-5-20
pubmed:abstractText
A cDNA for the rat liver sodium-dependent bile acid cotransporter was expressed in COS-7 cells to study the functional properties of the translated protein in a mammalian cell line. A 1.2-kb insert was ligated into a pMAMneo vector and transiently transfected using electroporation. After optimal conditions were established, the transiently transfected COS cells were screened with fluorescent-conjugated labeled bile acids for evidence of expression of the cotransporter after 48 h. The uptake of [3H]taurocholate ([3H]TC) was then determined in cells transfected with or without the bile acid insert. Progressive uptake of [3H]TC (0.45 microM) was observed for 30 min in the presence of sodium. In contrast, no uptake of [3H]TC was observed in the absence of sodium, in nontransfected COS cells, or in COS cells transfected with the empty plasmid. Kinetic studies revealed a Michaelis constant (Km) of 29 microM, essentially identical to the Km of this cotransporter described in intact rat hepatocytes and membrane vesicles. Uptake of [3H]TC (5.0 microM) at 5 min (n = 3-6) was inhibited by 100 microM taurochenodeoxycholic acid (81%), tauroursodeoxycholic acid (77%), cholic acid (55%), chenodeoxycholic acid (74%), and ursodeoxycholic acid (56%) but not by 100 microM taurodehydrocholate, 1 mM probenecid, or 100 microM bilirubin. In contrast, bumetanide (500 microM) inhibited [3H]TC uptake by 52%. These studies indicate that the isolated cDNA codes for a physiological bile acid transporter present in rat hepatocytes and that posttranslational factors present in mammalian cells may not be as important in defining properties of this cotransport system.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G382-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Expression and characterization of a functional rat liver Na+ bile acid cotransport system in COS-7 cells.
pubmed:affiliation
Liver Center, Yale University School of Medicine, New Haven, Connecticut 06510-8050.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't