Linked Life Data

8074188

Source:http://linkedlifedata.com/resource/pubmed/id/8074188

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2 Pt 1
pubmed:dateCreated
1994-9-23
pubmed:abstractText
The A10 line of vascular smooth muscle cells has Na+ dependent transport systems for alanine, proline, and Pi, whereas uptake of leucine, myo-inositol and D-glucose is Na+ independent. When A10 cells were incubated for 4 h in medium made hypertonic by addition of sucrose, there was a marked increase in Na(+)-dependent transport of alanine and proline but no change in Na(+)-dependent Pi uptake or Na(+)-independent uptake of leucine and inositol. Intracellular alanine content was increased 61% by the hypertonic treatment. Other nonpenetrating solutes, such as cellobiose and mannitol, reproduced the effect of sucrose, but urea, a penetrating solute, did not. Studies with 2-(methylamino)-isobutyric acid revealed that the upregulation by hypertonicity involved only system A. Increases in alanine and proline uptake also occurred after incubating the cells in isotonic medium containing 0.1 mM ouabain, suggesting that an increase in intracellular Na+ may be part of the intracellular signal for upregulation of system A. Hypertonic upregulation of Na(+)-dependent alanine transport occurred also in primary cultures of vascular smooth muscle cells. The response was blocked by actinomycin D and cycloheximide, indicating that gene transcription and protein synthesis play important roles in the mechanism leading to increased alanine uptake. We conclude that vascular smooth muscle cells, during prolonged hypertonic stress, activate system A and accumulate specific neutral amino acids which may act as organic osmolytes to help maintain normal cell volume.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C529-36
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Hypertonic upregulation of amino acid transport system A in vascular smooth muscle cells.
pubmed:affiliation
Department of Physiology and Biophysics, Indiana University School of Medicine, Indianapolis 46202-5120.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't