Linked Life Data

17579662

Source:http://linkedlifedata.com/resource/pubmed/id/17579662

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-8-23
pubmed:abstractText
The kidney is the major regulator of potassium homeostasis. In addition to the ROMK channels, large conductance Ca(2+)-activated K(+) (BK) channels are expressed in the apical membrane of the aldosterone sensitive distal nephron where they could contribute to renal K(+) secretion. We studied flow-induced K(+) secretion in BK channel alpha-subunit knockout (BK(-/-)) mice by acute pharmacologic blockade of vasopressin V(2) receptors, which caused similar diuresis in wild-type and knockout mice. However, wild-type mice, unlike the BK(-/-), had a concomitant increase in urinary K(+) excretion and a significant correlation between urinary flow rate and K(+) excretion. Both genotypes excreted similar urinary amounts of K(+) irrespective of K(+) diet. This was associated, however, with higher plasma aldosterone and stronger expression of ROMK in the apical membrane of the aldosterone-sensitive portions of the distal nephron in the knockout than in the wild-type under control diet and even more so with the high-K(+) diet. High-K(+) intake significantly increased the renal expression of the BK channel in the wild-type mouse. Finally, despite the higher plasma K(+) and aldosterone levels, BK(-/-) mice restrict urinary K(+) excretion when placed on a low-K(+) diet to the same extent as the wild-type. These studies suggest a role of the BK channel alpha-subunit in flow-induced K(+) secretion and in K(+) homeostasis. Higher aldosterone and an upregulation of ROMK may compensate for the absence of functional BK channels.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0085-2538
pubmed:author
pubmed:issnType
Print
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
566-73
pubmed:dateRevised
2010-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The role of the BK channel in potassium homeostasis and flow-induced renal potassium excretion.
pubmed:affiliation
Institute of Pharmacology and Toxicology, Medical Faculty of the Eberhard Karls University, Wilhelmstrasse 56, 72074 Tübingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't