Linked Life Data

8447404

Source:http://linkedlifedata.com/resource/pubmed/id/8447404

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2 Pt 1
pubmed:dateCreated
1993-4-2
pubmed:abstractText
The role of membrane voltage as a driving force for the hepatic uptake and secretion of fluorescent bile salts has been examined in isolated hepatocyte couplets. The present study demonstrates that the fluorescent bile salt derivative (N-[7-(nitrobenz-2-oxa- 1,3-diazol-4-yl)]-7-amino-3 alpha, 12 alpha-dihydroxy-5-cholan-24-oyl)-2-aminoethanesulfonate (7 beta-NBD-NCT) is taken up into hepatocytes by a saturable process with a Kt of 2.7 microM. Uptake rate was reduced by only 22% after total Na+ replacement and was independent of transmembrane potential difference over a range of -135 to +25 mV. In contrast, secretion into the canalicular space was strongly dependent on membrane voltage over the range from -34 to 0 mV in a manner consistent with electrodiffusion of an anion. Fitting the secretion time course to that predicted by electrodiffusion demonstrated that only approximately 50% of total secretion can result from electrodiffusion. Studies in isolated perfused liver confirmed this observation that depolarization caused a decrease in bile salt secretion rate. These results demonstrate that 7 beta-NBD-NCT is transported by a neutral uptake process at the sinusoidal membrane and is secreted across the canalicular membrane in part by electrogenic transport. This suggests that voltage changes could be a common pathway resulting in impaired organic anion secretion in diverse cholestatic syndromes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
264
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G220-30
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Electroneutral uptake and electrogenic secretion of a fluorescent bile salt by rat hepatocyte couplets.
pubmed:affiliation
Department of Medicine and Liver Center, Yale University School of Medicine, New Haven, Connecticut 06514.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't