Document Detail


Influence of insulin, glucocorticoids and glucose on glycogen synthase activity in hepatocyte cultures.
MedLine Citation:
PMID:  6774764     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A preparation method of monolayer cultures from rat hepatocytes with up to 95% plating efficiency is described. Cell number and DNA content per dish remained stable during 3 days in culture in hormone-free media containing 10 mM glucose. The cellular content of protein was decreased to 50% in the same time period. Glycogen content and specific activity of glycogen synthase present in the original hepatocyte suspension declined rapidly during 2 days in the absence of hormones. Addition of 20 nM insulin or 0.1 microM triamcinolone did not prevent this loss of cellular contents, however, in the simultaneous presence of both hormones the original levels of protein, glycogen and glycogen synthase were maintained for 2 days. In 2-day-old hepatocytes an increase of glycogen synthase activity could be evoked by insulin in the presence of 20 or even 5 mM glucose provided these cells had been precultivated in the presence of triamcinolone. Both the I-form and the activity determined at 6.7 mM glucose 6-phosphate rose after exposition of hepatocytes to insulin and 20 mM glucose, whereas a 'total activity' being unchanged by hormone treatment of the cells was only obtained if 50 mM glucose 6-phosphate were present during determination of enzyme activity. Addition of 10 microgram/ml cycloheximide during incubation of the cells reduced the effect of 20 mM glucose and abolished that of insulin on glycogen synthase and on the corresponding glycogen deposition. It is discussed that insulin and glucose activate glycogen synthase in two successive steps by regulating synthesis and activity of an interconverting enzyme.
Authors:
C Schudt
Related Documents :
15192044 - Intracerebroventricular infusion of glucose, insulin, and the adenosine monophosphate-a...
6432774 - Glucagon and glucose as major regulators of glycogen metabolism in primary cultured rat...
11319724 - Contribution of net hepatic glycogen synthesis to disposal of an oral glucose load in h...
11912564 - Creatine supplementation alters insulin secretion and glucose homeostasis in vivo.
24690504 - Safe and appropriate use of insulin and other antihyperglycemic agents in hospital.
2044434 - Insulin resistance. a multifaceted syndrome responsible for niddm, obesity, hypertensio...
Publication Detail:
Type:  Comparative Study; Journal Article    
Journal Detail:
Title:  Biochimica et biophysica acta     Volume:  629     ISSN:  0006-3002     ISO Abbreviation:  Biochim. Biophys. Acta     Publication Date:  1980 May 
Date Detail:
Created Date:  1980-12-18     Completed Date:  1980-12-18     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0217513     Medline TA:  Biochim Biophys Acta     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  499-509     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Cells, Cultured
Cycloheximide / pharmacology
Glucocorticoids / pharmacology*
Glucose / pharmacology*
Glycogen Synthase / metabolism*
Insulin / pharmacology*
Liver / drug effects*,  enzymology
Liver Glycogen / metabolism
Male
Rats
Chemical
Reg. No./Substance:
0/Glucocorticoids; 0/Liver Glycogen; 11061-68-0/Insulin; 50-99-7/Glucose; 66-81-9/Cycloheximide; EC 2.4.1.11/Glycogen Synthase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Respiration of 14CO2 by intact animals of various species given L-[1-14C]fucose or D-[1-14C]arabinos...
Next Document:  The interaction of the K88 antigen with porcine intestinal epithelial cell brush borders.