title: Involvement of cyclic AMP-dependent protein kinase on the phosphorylase kinase inhibition by glucose-6-phosphate in adipose tissue extracts.
abstract: In order to achieve further clarification of the regulation of glycogenolysis in adipose tissue, we studied the effect of glucose-6-phosphate on phosphorylase activation in Sephadex G-25 filtrate of adipose tissue. The activity of phosphorylase kinase was decreased by 50% and by 75% in the presence of 0.5 mM and 2 mM of glucose-6-phosphate, respectively. This inhibition could be partially prevented by 0.5 mM AMP. Furthermore, we investigated the influence of glucose-6-phosphate on the effect of cyclic-AMP-dependent protein kinase on the activation of phosphorylase. The addition of cyclic-AMP and cyclic-AMP-dependent protein kinase caused a decrease in the inhibition of the phosphorylase activation by glucose-6-phosphate. Also, the glucose-6-phosphate at physiological concentration, decreased adipose tissue cyclic-AMP-dependent protein kinase activity.
mesh_terms: D000249:Adenosine Monophosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000273:Adipose Tissue / Q000201:enzymology*; D000818:Animals; D000242:Cyclic AMP / Q000494:pharmacology; D019298:Glucose-6-Phosphate; D005958:Glucosephosphates / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D010764:Phosphorylase Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010762:Phosphorylase a / Q000096:biosynthesis; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014020:Tissue Extracts / Q000032:analysis
chemical_list: D005958:Glucosephosphates; D014020:Tissue Extracts; D000249:Adenosine Monophosphate; D019298:Glucose-6-Phosphate; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D010762:Phosphorylase a; D011494:Protein Kinases; D010764:Phosphorylase Kinase