Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-8-28
pubmed:abstractText
Epithelial cells contain two distinct membrane surfaces, the apical and basolateral plasma membranes, which have different lipid and protein compositions. In order to assess the effect of the compositional differences of the apical and basolateral membranes on their ability to undergo cholesterol efflux, MDCK cells were radiolabeled with [3H]cholesterol and grown as a polarized monolayer on filter inserts, that separate the upper apical compartment from the lower basolateral compartment. The rate of cholesterol efflux from the basolateral membrane into media containing HDL in the basolateral compartment was 6.3%/h +/-0.7, whereas HDL-mediated efflux from the apical membrane was approximately 3-fold slower (1.9%/h +/-0.3). In contrast, Fu5AH cells, which do not form distinct polarized membrane domains, had a similar rate of HDL-mediated cholesterol efflux into the apical and basolateral compartments. Similar to HDL, other cholesterol acceptors, namely LDL, bovine serum albumin, and a lipid emulsion, also showed a decreased rate of cholesterol efflux from the apical membrane surface versus the basolateral membrane. Compared to the basolateral membrane, the apical membrane was also found to be more resistant to cholesterol oxidase treatment, to bind less HDL, and to take up less cholesterol from the medium. In conclusion, cholesterol efflux occurred less readily from the apical membrane than from the basolateral membrane for all types of acceptors tested. These results suggest that differences in the composition of the apical and basolateral membrane lead to a relative decrease in cholesterol desorption from the apical membrane and hence a reduced rate of cholesterol efflux.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2275
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1231-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Differential rate of cholesterol efflux from the apical and basolateral membranes of MDCK cells.
pubmed:affiliation
Clinical Pathology Department, National Institutes of Health, Clinical Center, Bethesda, MD 20892, USA.
pubmed:publicationType
Journal Article, Comparative Study