Linked Life Data

8166281

Source:http://linkedlifedata.com/resource/pubmed/id/8166281

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
We have recently shown (D. Sorrentino, R.B. Robinson, C.-L. Kiang, and P.D. Berk. J. Clin. Invest. 84: 1325-1333, 1989) that, in a variety of isolated cell types, the uptake of oleate at physiological albumin concentrations is consistent with traditional pharmacokinetic theory (i.e., driven by unbound ligand). Lower albumin concentrations were associated with a deviant uptake pattern for which alternative theories have been proposed. Whether other classes of organic anions exhibit similar behavior is unknown. Therefore, we examined the effect of albumin on uptake of two widely studied organic anions, sulfobromophthalein (BSP) and taurocholate. Initial uptake velocity of [35S]BSP and [3H]taurocholate by isolated hepatocytes was studied employing a fixed albumin concentration and ligand-to-albumin molar ratios from 0.01:1 to 2:1 for taurocholate and 0.031:1 to 0.75:1 for BSP. In other experiments, albumin and ligand were altered in parallel, keeping their molar ratio constant. Unbound taurocholate concentrations were measured directly by equilibrium dialysis; unbound BSP concentrations were calculated from published data (K.J. Baker and S.E. Bradley. J. Clin. Invest. 45: 281-287, 1966). At 600 microM albumin, uptake of both ligands was a function of the unbound ligand concentration. At low ligand-to-albumin molar ratios and consequent unbound ligand concentrations this relationship was linear; over the entire range of unbound ligand concentrations studied, both ligands exhibited Michaelis-Menten kinetics, with definable maximal velocity and Michaelis constant values. At low albumin concentrations, the relationships between uptake and unbound ligand were unchanged for taurocholate; however, BSP exhibited altered kinetics similar to those observed with oleate. Nontraditional uptake kinetics at low albumin concentrations appear to correlate with very high affinity for albumin.
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
G425-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Unbound ligand drives hepatocyte taurocholate and BSP uptake at physiological albumin concentration.
pubmed:affiliation
Department of Medicine (Division of Liver Diseases), Mount Sinai School of Medicine, New York, New York 10029.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't