Linked Life Data

9049167

Source:http://linkedlifedata.com/resource/pubmed/id/9049167

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1997-6-10
pubmed:abstractText
Voltage-dependent K+ currents (Kv) may play a role in hypoxic pulmonary vaso constriction. The effects of changes in extracellular pH (pHo) and intracellular pH (pHi) on Kv currents in smooth muscle cells isolated from canine pulmonary artery were studied using the amphotericin B perforated-patch technique for whole-cell recording. Under these conditions, cellular mechanisms for pHi regulation remain intact, and the effects of pHo were examined by directly changing the pH of external solutions and changes in pHi were produced by external application of weak extracellular acids and bases and the cation/H+ ionophore, nigericin. Ca(2+)-free external solutions were used to isolate whole-cell Kv currents from contaminating Ca(2+)-activated K+ currents. Extracellular acidification (pHo = 6.4-7.0) reduced Kv currents, produced a positive voltage shift in steady-state activation and reduced maximum Kv conductance (gK). Extracellular alkalinization (pHo = 8.0-8.4) increased Kv currents, produced a small negative voltage shift in steady-state activation, and increased gK. Intracellular acidification produced by exposure of cells to external sodium butyrate (20 mM) or nigericin (5 micrograms/ml) increased Kv currents, produced a negative voltage shift in steady-state activation, and increased gK. Intracellular alkalinization produced by exposure of cells to external trimethylamine (20 mM) reduced Kv currents, produced a small positive voltage shift in steady-state activation and reduced gK. These results suggest that the effects of pHo and pHi on Kv currents are distinctly different, but are consistent with reported effects of pHo and pHi on hypoxic pulmonary vasoconstriction, suggesting that such modulation may be mediated in party by pH-induced alterations in Kv channel activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
433
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
758-65
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
pH regulation of voltage-dependent K+ channels in canine pulmonary arterial smooth muscle cells.
pubmed:affiliation
Department of Physiology and Cell Biology/351, University of Nevada School of Medicine, Reno 89557-0046, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.