Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1992-12-4
pubmed:abstractText
1. The effects of phorbol esters on canine Purkinje fibers were examined using conventional microelectrode techniques. 2. 12-O-Tetradecanoylphorbol-13-acetate (TPA) and 4-beta-phorbol-12,13-dibutyrate (PDB), which are specific activators of protein kinase C (PKC), decreased the action potential amplitude and the maximum rate of depolarization (Vmax) at 3 x 10(-7) M or higher. These phorbol esters had little effect on the resting potential. 3. PDB (1-3 x 10(-7) M) also reduced the contractile force, accompanied with initial increase (in 5 out of 8 experiments), whereas TPA did not decrease it to any significant extent. 4. An inactive analog of phorbol esters, 4-alpha-phorbol-12,13-didecanoate (PDD), decreased the action potential amplitude and Vmax, and slightly increased the action potential duration. However, PDD failed to produce any inotropic effect. 5. Post-rest potentiation of the contractile force after a rest from stimulation for 30 sec was inhibited in the presence of 3-10 x 10(-7) M TPA or 3 x 10(-7) M PDB. 6. Isoproterenol 10(-7) M augmented the action of PDB 3 x 10(-7) M. 7. These results suggest that activation of PKC may modulate myocardial Ca2+ homeostasis and influence the excitation-contraction process.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0306-3623
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
847-52
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
The responses to phorbol esters which stimulated protein kinase C in canine Purkinje fibers.
pubmed:affiliation
Department of Pharmacology, Nara Medical University, Japan.
pubmed:publicationType
Journal Article, Comparative Study