Linked Life Data

8997334

Source:http://linkedlifedata.com/resource/pubmed/id/8997334

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 2
pubmed:dateCreated
1997-2-20
pubmed:abstractText
The efficacy with which sulfonylurea drugs inhibit cardiac ATP-sensitive K+ (KATP) channels is reduced during metabolic compromise and cellular contracture. Disruption of the actin microfilament network, which occurs under similar conditions, reduces the sensitivity of the channel toward intracellular ATP. To investigate whether a disrupter of actin microfilaments could also affect the responsiveness of the KATP channel to sulfonylurea drugs, single-channel currents were measured in the inside-out configuration of excised patches from guinea pig ventricular myocytes. Treatment of the internal side of patches with deoxyribonuclease (DNase) I (100 micrograms/ml), which forms complexes with G actin and prevents actin filament formation, antagonized sulfonylurea-induced inhibition of KATP channels that was coupled with a loss of sensitivity to ATP. The apparent dissociation constant and Hill coefficient for the inhibitory effect of glyburide, a prototype sulfonylurea, on KATP-channel opening were, respectively, 0.13 microM and 0.95 before and 2.7 microM and 0.98 after DNase treatment. DNase did not alter intraburst kinetic properties of the channel. When DNase was denatured or coincubated with purified actin (200 micrograms/ml), it no longer decreased glyburide-induced channel inhibition. This suggests that sulfonylurea-inhibitory gating of cardiac KATP channels may also be regulated through a mechanism involving subsarcolemmal actin microfilament networks.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H2710-6
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
A disrupter of actin microfilaments impairs sulfonylurea-inhibitory gating of cardiac KATP channels.
pubmed:affiliation
Department of Medicine and Pharmacology, Mayo Clinic, Mayo Foundation, Rochester, Minnesota 55905, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't