Linked Life Data

2221082

Source:http://linkedlifedata.com/resource/pubmed/id/2221082

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 1
pubmed:dateCreated
1990-11-21
pubmed:abstractText
Alveolar type II cells require a source of palmitic acid for synthesis of dipalmitoyl phosphatidylcholine (DPPC), a major constituent of pulmonary surfactant. Previous studies indicated that maximal rates of DPPC synthesis are achieved only if exogenous palmitate is available to the type II cell. Little is known of the mechanisms by which fatty acids enter type II cells. To determine if uptake is mediated by a membrane carrier system, as described in other cell types, we examined the kinetics of palmitate uptake. Using freshly isolated rabbit type II cells, we demonstrated that radiolabeled palmitate uptake was maximal and linear for 45 s; after 1 min the apparent rate of uptake declined. The initial uptake phase was taken as a measure of cellular fatty acid influx because intracellular radiolabeled palmitate remained 80% nonesterified at this time but was 55% esterified by 2 min. Cellular influx of palmitate showed saturation kinetics with increasing concentration of nonalbumin bound palmitate. Michaelis constant was 52.6 nM, and maximum velocity was 152 pmol.10(6) cells-1.min-1. The hypothesis that saturable cellular influx of palmitate is likely linked to the previously identified membrane fatty acid binding protein (MFABP) was supported by Western-blot analysis of rat lung tissue with an antibody to MFABP that demonstrated the presence of this carrier protein in lung tissue. These data suggest that palmitate uptake by type II cells is saturable and may be mediated by a membrane-associated carrier as described in other cell types.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L206-12
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Uptake of palmitic acid by rabbit alveolar type II cells.
pubmed:affiliation
Department of Pediatrics, University of Rochester School of Medicine, New York 14642.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't