Indirect versus direct routes of hepatic glycogen synthesis

Irwin J. Kurland, S. J. Pilkis

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

During refeeding after a brief period of starvation, glucose carbon is deposited into hepatic glycogen by both a direct and an indirect route. In the indirect route glucose is first metabolized to 3-carbon precursors, which then transverse the gluconeogenic pathway before being deposited into glycogen. Recent studies have yielded widely different estimates of the percentage of glucose carbon that follows the indirect route. Work summarized here demonstrates that the relative contributions of glucose carbon to hepatic glycogen formation by the indirect and direct pathways are greatly dependent on experimental design, and at least in vitro, are possibly dependent on the extent of glycogen/glucose 1-P recycling. Under physiological refeeding conditions in vivo, both pathways are used, each contributing approximately 50% of the amount of carbon appearing in glycogen. The level of glucokinase activity does not appear to be responsible for poor glucose utilization in liver. Poor glucose utilization in isolated liver preparations may result from the absence of a neurophysiological feedback loop that senses the arterial/portal glucose gradient and then regulates whole liver glucose uptake.

Original languageEnglish (US)
Pages (from-to)2277-2281
Number of pages5
JournalFASEB Journal
Volume3
Issue number11
StatePublished - 1989
Externally publishedYes

Fingerprint

Liver Glycogen
glycogen
Glucose
liver
glucose
synthesis
Carbon
Glycogen
carbon
Liver
refeeding
glucokinase
Glucokinase
Recycling
Starvation
Design of experiments
recycling
starvation
Research Design
experimental design

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry
  • Cell Biology

Cite this

Indirect versus direct routes of hepatic glycogen synthesis. / Kurland, Irwin J.; Pilkis, S. J.

In: FASEB Journal, Vol. 3, No. 11, 1989, p. 2277-2281.

Research output: Contribution to journalArticle

Kurland, IJ & Pilkis, SJ 1989, 'Indirect versus direct routes of hepatic glycogen synthesis', FASEB Journal, vol. 3, no. 11, pp. 2277-2281.
Kurland, Irwin J. ; Pilkis, S. J. / Indirect versus direct routes of hepatic glycogen synthesis. In: FASEB Journal. 1989 ; Vol. 3, No. 11. pp. 2277-2281.
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