These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Evidence for adenylate cyclase-coupled A1-adenosine receptors on ventricular cardiomyocytes from adult rat and dog heart.
    Author: Henrich M, Piper HM, Schrader J.
    Journal: Life Sci; 1987 Nov 23; 41(21):2381-8. PubMed ID: 2824951.
    Abstract:
    Isolated metabolically stable cardiomyocytes from adult rats and mongrel dogs were used to characterize the mechanism underlying the antiadrenergic effect of adenosine. In a system not affected by cellular heterogeneity, isoproterenol (3 x 10(-9) M - 10(-5) M) in the presence of adenosine deaminase (5U/ml) dose dependently increased cellular cAMP (5-80 pmol/mg). The effect of isoproterenol (0.1 microM) was inhibited by various adenosine derivatives, the rank order of potency being in the rat: (-)-N6-(R-phenyl-isopropyl)-adenosine (R-PIA) greater than 5'-N-ethylcarboxamidoadenosine (NECA) greater than S-PIA, and in the dog NECA greater than R-PIA greater than S-PIA. The cAMP increase induced by forskolin (1 microM) was attenuated in the rat by R-PIA. 8-phenyltheophylline (3 microM) antagonized the effect of R-PIA on isoproterenol-stimulated cAMP formation. Basal cAMP content was not influenced by R-PIA or NECA. Omission of adenosine deaminase from the incubation medium attenuated the isoproterenol-induced cAMP increase in the rat by about 30%. Our findings provide evidence for the presence of adenylate cyclase-coupled A1-adenosine receptors on cardiomyocytes which may mediate the antiadrenergic effect of adenosine in the heart.
    [Abstract] [Full Text] [Related] [New Search]