Linked Life Data

2428003

Source:http://linkedlifedata.com/resource/pubmed/id/2428003

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1986-10-21
pubmed:abstractText
The calcium current (ICa) in the heart is increased by phosphorylation of a protein which is part of, or close to, the Ca channel. The phosphorylation is catalysed by cAMP-dependent protein kinase (cAMP-PK). The question whether dephosphorylated channels are available to open on depolarization was examined in ventricular myocytes of guinea pig by recording whole cell ICa during dialysis with either regulatory (R) subunit of cAMP-PK or protein kinase inhibitor (PKI) or adenosine-5'-(gamma-thio)-triphosphate (ATP gamma S). The following results were obtained: 1) R subunit reduced and PKI reversed the isoprenaline (ISP)-induced enhancement of ICa, suggesting their ability to inhibit cAMP-PK. 2) R subunit and PKI, however, reduced basal (i.e. non beta-adrenergically stimulated) ICa only by about 20%. 3) Dialysis with ATP gamma S resulted in a slow increase in basal ICa, presumably due to dephosphorylation-resistant thiophosphorylation. 4) When, however, the cell was dialyzed with PKI the effect of ATP gamma S was almost completely suppressed, suggesting no detectable phosphorylation related to the channel activity in this condition. These results support the view that even in the dephosphorylated state Ca channels are available to open on depolarization and that phosphorylation by cAMP-PK increases the opening probability.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
407
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
123-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Modulation of Ca current during the phosphorylation cycle in the guinea pig heart.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't