Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1 Pt 1
pubmed:dateCreated
1996-12-19
pubmed:abstractText
Liddle's disease is an autosomal dominant genetic disorder characterized by severe low renin hypertension ("pseudoaldosteronism") that has been genetically linked to a locus on chromosome 16 encoding the beta-subunit of an amiloride-sensitive Na+ channel (ASSC) (15). Peripheral blood lymphocytes (PBL) express ASSC that are functionally indistinguishable from those expressed by Na(+)-reabsorbing renal epithelial cells (3, 5). The amiloride-sensitive Na+ conductance in PBL from affected and unaffected individuals from the original Liddle's pedigree was examined using whole cell patch clamp. Typically, the basal Na+ currents in cells from affected individuals were maximally activated. Basal Na+ currents in cells from unaffected individuals were minimal and could be maximally activated by superfusion with 8-(4-chlorophenylthio)adenosine 3',5'-cyclic monophosphate (CPT-cAMP). Affected cells could not be further stimulated with CPT-cAMP. Superfusion with a supermaximal concentration of amiloride (2 microM) inhibited both the cAMP-activated Na+ conductance in unaffected cells and the constitutively activated inward conductance in affected cells. Cytosolic addition of a peptide identical to the terminal 10 amino acids of the truncated beta-subunit normalized the cAMP-mediated but not the pertussis toxin-induced regulation of the mutant ASSC. The findings show that lymphocyte ASSC are constitutively activated in affected individuals, that a mutation of the beta-subunit alters ASSC responsiveness to specific regulatory effectors, and that the cellular mechanism responsible for the pathophysiology of Liddle's disease is abnormal regulation of Na+ channel activity. These findings have important diagnostic and therapeutic implications and provide a cellular phenotype for the diagnosis of pseudoaldosteronism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C208-13
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Liddle's disease: abnormal regulation of amiloride-sensitive Na+ channels by beta-subunit mutation.
pubmed:affiliation
Department of Medicine, University of Alabama at Birmingham, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't