title: A phospho-oligosaccharide mimics insulin action on glycogen phosphorylase and pyruvate kinase activities in isolated rat hepatocytes.
abstract: A phospho-oligosaccharide which is the polar head group of a novel insulin-sensitive glycophospholipid has recently been involved in insulin action. We have investigated the insulin-like effects of this phospho-oligosaccharide on both glycogen phosphorylase a and pyruvate kinase activities of hepatocytes incubated in the presence of glucagon (0.1 nM). Similarly to insulin, the phospho-oligosaccharide antagonized glucagon-dependent activation of glycogen phosphorylase, as well as the inactivation of pyruvate kinase caused by this hormone. The antagonistic action of the phospho-oligosaccharide on glucagon effects was dose-dependent. Furthermore, it partially antagonized glucagon-stimulated cyclic AMP levels. These results support the hypothesis that this phospho-oligosaccharide mediates at least some insulin actions in hepatocytes.
authors.forename: J F
authors.initials: JF
authors.lastname: Alvarez
authors.forename: M A
authors.initials: MA
authors.lastname: Cabello
authors.forename: J E
authors.initials: JE
authors.lastname: Felíu
authors.forename: J M
authors.initials: JM
authors.lastname: Mato
mesh_terms: D000818:Animals; D005934:Glucagon / Q000037:antagonists & inhibitors / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D007700:Kinetics; D008099:Liver / Q000032:analysis / Q000187:drug effects / Q000201:enzymology*; D009844:Oligosaccharides / Q000494:pharmacology*; D010762:Phosphorylase a / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006005:Phosphorylases / Q000378:metabolism*; D011770:Pyruvate Kinase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D007328:Insulin; D009844:Oligosaccharides; D005934:Glucagon; D010762:Phosphorylase a; D006005:Phosphorylases; D011770:Pyruvate Kinase