Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
ROLE OF GLUCOSE AND INSULIN IN REGULATING GLYCOGEN-SYNTHASE AND PHOSPHORYLASE ACTIVITIES IN RAINBOW-TROUT HEPATOCYTES
Autore:
PEREIRA C; VIJAYAN MM; STOREY KB; JONES RA; MOON TW;
Indirizzi:
UNIV BRITISH COLUMBIA,DEPT ANIM SCI,208 2357 MAIN MALL VANCOUVER BC V6T 1Z4 CANADA UNIV OTTAWA,DEPT BIOL,OTTAWA CARLETON INST BIOL OTTAWA ON K1N 6N5 CANADA
Titolo Testata:
Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology
fascicolo: 1, volume: 165, anno: 1995,
pagine: 62 - 70
SICI:
0174-1578(1995)165:1<62:ROGAII>2.0.ZU;2-J
Fonte:
ISI
Lingua:
ENG
Soggetto:
NUCLEAR MAGNETIC-RESONANCE; SALMO-GAIRDNERI; LIVER; METABOLISM; GLUCONEOGENESIS; GLUCAGON; C-13; CARBOHYDRATE; SPECTROSCOPY; INACTIVATION;
Keywords:
GLYCOGEN; HEPATOCYTE; INSULIN; C-13 NMR; RAINBOW TROUT; ONCORHYNCHUS MYKISS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
43
Recensione:
Indirizzi per estratti:
Citazione:
C. Pereira et al., "ROLE OF GLUCOSE AND INSULIN IN REGULATING GLYCOGEN-SYNTHASE AND PHOSPHORYLASE ACTIVITIES IN RAINBOW-TROUT HEPATOCYTES", Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology, 165(1), 1995, pp. 62-70

Abstract

This study, using C-13 nuclear magnetic resonance spectroscopy showedenrichment of glycogen carbon (C1) from C-13-labelled (C1) glucose indicating a direct pathway for glycogen synthesis from glucose in rainbow trout (Oncorhynchus mykiss) hepatocytes. There was a direct relationship between hepatocyte glycogen content and total glycogen synthase,total glycogen phosphorylase and glycogen phosphorylase a activities,whereas the relationship was inverse between glycogen content and % glycogen synthase a and glycogen synthase a/glycogen phosphorylase a ratio. Incubation of hepatocytes with glucose (3 or 10 mmol . l(-1)) didnot modify either glycogen synthase or glycogen phosphorylase activities. Insulin (porcine, 10(-8) mol . l(-1)) in the medium significantlydecreased total glycogen phosphorylase and glycogen phosphorylase a activities, but had no significant effect on glycogen synthase activities when compared to the controls (absence of insulin). In the presenceof 10 mmol . l(-1) glucose, insulin increased % glycogen synthase a and decreased % glycogen phosphorylase a activities in trout hepatocytes. Also, the effect of insulin on the activities of % glycogen synthase a and glycogen synthase a/glycogen phosphorylase a ratio were more pronounced at low than at high hepatocyte glycogen content. The resultsindicate that in trout hepatocytes both the glycogen synthetic and breakdown pathways are active concurrently in vitro and any subtle alterations in the phosphorylase to synthase ratio may determine the hepatic glycogen content. Insulin plays an important role in the regulation of glycogen metabolism in rainbow trout hepatocytes. The effect of insulin on hepatocyte glycogen content may be under the control of several factors, including plasma glucose concentration and hepatocyte glycogen content.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 26/09/20 alle ore 11:58:44