title: The ability of adenosine to decrease the concentration of fructose 2,6-bisphosphate in isolated hepatocytes. A cyclic AMP-mediated effect.
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.
mesh_terms: D015762:2-Chloroadenosine; D000241:Adenosine / Q000031:analogs & derivatives / Q000494:pharmacology*; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D005635:Fructosediphosphates / Q000378:metabolism*; D005934:Glucagon / Q000494:pharmacology; D005943:Gluconeogenesis / Q000187:drug effects; D006598:Hexosediphosphates / Q000378:metabolism*; D066298:In Vitro Techniques; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D005635:Fructosediphosphates; D006598:Hexosediphosphates; D015762:2-Chloroadenosine; C027652:fructose 2,6-diphosphate; D005934:Glucagon; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D000241:Adenosine