Linked Life Data

2415919

Source:http://linkedlifedata.com/resource/pubmed/id/2415919

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-1-6
pubmed:abstractText
Dose-response relations for the increase in the amplitude of Ca current (ICa) on external application of isoprenaline (ISP) and internally applied cyclic AMP (cAMP) or catalytic subunit of cAMP-dependent protein kinase (C subunit) were established in single ventricular cells of the guinea pig. An intracellular dialysis technique was used. The threshold concentration was for ISP 10(-9) M, for cAMP 3 microM (pipette concentration to which 10(-5) M 3-isobutyl-1-methylxanthine was added) and for C subunit around 0.4 microM (pipette concentration). The concentrations for the half-maximal effect were 3.7 X 10(-8) M (ISP), 5.0 microM (cAMP) and 0.95 microM (C subunit) and for the maximum effect 10(-6) M (ISP), 15-20 microM (cAMP) and 3-4 microM (C subunit). For all three agents the maximum increase in the Ca current density was similar (a factor of 3-4), suggesting that they converge on the same site of the Ca channel. Accordingly, the effects of cAMP and C subunit on ICa were non-additive to those of ISP. From these data the relationship both between concentrations of ISP and cAMP and between those of cAMP and active C subunit in terms of their effects on ICa could be estimated and were compared with those obtained in broken cell preparations. A competitive inhibitor of phosphorylation, 5'-adenylyl-imidodiphosphate (5 mM), greatly reduced the effects of ISP and C subunit on ICa. Cell dialysis with 3 mM adenosine-5'-(gamma-thio)-triphosphate, which produces a dephosphorylation-resistant phosphorylation, markedly potentiated the effects of ISP and cAMP on ICa.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
405
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
285-93
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
On the mechanism of beta-adrenergic regulation of the Ca channel in the guinea-pig heart.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't