Protein kinase Cepsilon and the antiadrenergic action of adenosine in rat ventricular myocytes
UMass Chan Affiliations
Deppartment of PhysiologyDocument Type
Journal ArticlePublication Date
2004-06-19Keywords
AdenosineAnimals
Electric Stimulation
Gene Expression
Green Fluorescent Proteins
Luminescent Proteins
Male
Myocardial Contraction
Myocytes, Cardiac
Protein Kinase C
Protein Kinase C-epsilon
Rabbits
Rats
Rats, Sprague-Dawley
Receptors, Adrenergic, beta
Transfection
Life Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Adenosine-induced antiadrenergic effects in the heart are mediated by adenosine A(1) receptors (A(1)R). The role of PKCepsilon in the antiadrenergic action of adenosine was explored with adult rat ventricular myocytes in which PKCepsilon was overexpressed. Myocytes were transfected with a pEGFP-N1 vector in the presence or absence of a PKCepsilon construct and compared with normal myocytes. The extent of myocyte shortening elicited by electrical stimulation of quiescent normal and transfected myocytes was recorded with video imaging. PKCepsilon was found localized primarily in transverse tubules. The A(1)R agonist chlorocyclopentyladenosine (CCPA) at 1 microM rendered an enhanced localization of PKCepsilon in the t-tubular system. The beta-adrenergic agonist isoproterenol (Iso; 0.4 microM) elicited a 29-36% increase in myocyte shortening in all three groups. Although CCPA significantly reduced the Iso-produced increase in shortening in all three groups, the reduction caused by CCPA was greatest with PKCepsilon overexpression. The CCPA reduction of the Iso-elicited shortening was eliminated in the presence of a PKCepsilon inhibitory peptide. These results suggest that the translocation of PKCepsilon to the t-tubular system plays an important role in A(1)R-mediated antiadrenergic actions in the heart.Source
Am J Physiol Heart Circ Physiol. 2004 Oct;287(4):H1721-9. Epub 2004 Jun 17. Link to article on publisher's siteDOI
10.1152/ajpheart.00224.2004Permanent Link to this Item
http://hdl.handle.net/20.500.14038/38384PubMed ID
15205171Related Resources
Link to article in PubMedae974a485f413a2113503eed53cd6c53
10.1152/ajpheart.00224.2004
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