The ability of adenosine to decrease the concentration of fructose 2,6-bisphosphate in isolated hepatocytes. A cyclic AMP-mediated effect.

R Bartrons; E Van Schaftingen; H G Hers

doi:10.1042/bj2180157

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PubMed · 6324747

The ability of adenosine to decrease the concentration of fructose 2,6-bisphosphate in isolated hepatocytes. A cyclic AMP-mediated effect.

R Bartrons·E Van Schaftingen·H G Hers

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Abstract

The presence of adenosine (25-250 microM) or of 2-chloroadenosine (2.5-100 microM) in the incubation medium caused a marked decrease in the concentration of fructose 2,6-bisphosphate in isolated hepatocytes. This effect was accompanied by an increase in the concentration of cyclic AMP, an activation of phosphorylase and of fructose 2,6-bisphosphatase, and an inactivation of pyruvate kinase and of 6-phosphofructo-2-kinase. As a rule, the changes in the fructose 2,6-bisphosphate-modifying system were slower but more persistent than those in the activities of phosphorylase and pyruvate kinase. The effect of the nucleoside to decrease the concentration of fructose 2,6-bisphosphate was not affected by an inhibitor of adenosine transport and could not be obtained in a liver high-speed supernatant. These data indicate that the effect of adenosine to decrease the concentration of fructose 2,6-bisphosphate is mediated by the stimulation of adenylate cyclase, secondary to the binding of adenosine to membranous receptors. Like glucagon, 2-chloroadenosine stimulated gluconeogenesis in isolated hepatocytes, whereas adenosine had an opposite effect.

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2-Chloroadenosine Adenosine Adenylyl Cyclases Animals Cyclic AMP Depression, Chemical Dose-Response Relationship, Drug Fructosediphosphates Glucagon Gluconeogenesis Hexosediphosphates In Vitro Techniques Liver Male Rats Rats, Inbred Strains Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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R Bartrons, E Van Schaftingen, H G Hers. 1984-02-15. The ability of adenosine to decrease the concentration of fructose 2,6-bisphosphate in isolated hepatocytes. A cyclic AMP-mediated effect.. https://doi.org/10.1042/bj2180157

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2-Chloroadenosine↗

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