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: Activation of tyrosine 3-monooxygenase in pheochromocytoma cells by adenosine.
    Author: Erny RE, Berezo MW, Perlman RL.
    Journal: J Biol Chem; 1981 Feb 10; 256(3):1335-9. PubMed ID: 6108963.
    Abstract:
    Adenosine increases the activity of tyrosine 3-monooxygenase in intact pheochromocytoma cells. The effect of adenosine is not dependent upon extracellular Ca2+, and is not accompanied by an increase in catecholamine secretion from the cells. Adenosine deaminase decreases the basal activity of tyrosine 3-monooxygenase, and almost completely abolishes the activation of this enzyme by adenosine. In cells treated with adenosine deaminase, 2-chloroadenosine causes a 2- to 5-fold increase in tyrosine 3-monooxygenase activity. 2-Chloroadenosine produces half-maximal activation at a concentration of 0.1 microM, and maximal activation at 10 microM. Incubation of cells with 2-chloroadenosine produces a stable activation of tyrosine 3-monooxygenase, as measured in vitro. Finally, 3-chloroadenosine increases the content of cAMP in pheochromocytoma cells, and increases the incorporation of 3H into cAMP in cells that have been preincubated with [3H]adenine. This rise in cAMP presumably mediates the activation of tyrosine 3-monooxygenase by 2-chloroadenosine. Adenosine appears to be an endogenous regulator of tyrosine 3-monooxygenase activity in pheochromocytoma cells.
    [Abstract] [Full Text] [Related] [New Search]