Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1 Pt 1
pubmed:dateCreated
1996-12-3
pubmed:abstractText
The immunosuppressants cyclosporin A (CyA), FK-506, and rapamycin (RAP) have multiple actions on target cells that appear to be mediated by interaction of drug-binding protein complexes. Both FK-506 and CyA, but not RAP, inhibit the Ca2(+)-dependent phosphatase, calcineurin, and in so doing have been found to inhibit Na(+)-K(+)-ATPase activity in various nephron segments. Of interest, FK-506 and RAP, but not CyA, are bound by the steroid receptor-associated FK-506-binding heat shock protein of 56 kDa, HSP56. To determine the physiological effect of this interaction on a steroid-mediated phenomenon, the effect of these agents on steroid-mediated Na+ transport in A6 cells was investigated. Aldosterone stimulation of Na+ transport and Na(+)-K(+)-ATPase activity are significantly inhibited by prolonged incubation with FK-506 and RAP. Although CyA inhibits basal Na(+)-K(+)-ATPase activity, it has no effect on aldosterone-induced Na+ transport or the aldosterone-induced increase in Na(+)-K(+)-ATPase activity. FK-506 inhibits the aldosterone-induced synthesis of G alpha i-3 protein but has no effect on glucocorticoid receptor number as quantified by Western blotting. The results suggest that FK-506 and RAP inhibit steroid-mediated Na+ transport at some pretranslational site. The common interaction of these agents with the steroid receptor-associated HSP56 might account for these findings.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C194-202
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
FK-506 and rapamycin but not cyclosporin inhibit aldosterone-stimulated sodium transport in A6 cells.
pubmed:affiliation
Laboratory of Epithelial Cell Biology, University of Pittsburg Medical Center, Pennsylvania, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't