Mechanism of gluconeogenesis inhibition in rat hepatocytes isolated after in vivo hypoxia. - Inserm - Institut national de la santé et de la recherche médicale Access content directly
Journal Articles American Journal of Physiology Year : 1995

Mechanism of gluconeogenesis inhibition in rat hepatocytes isolated after in vivo hypoxia.

Abstract

Gluconeogenesis was studied in hepatocytes isolated from fasted rats submitted to 24 h of hypoxic exposure (inspired O2 fraction 0.1) or to room air. Hepatocytes from hypoxic rats compared with controls exhibited a lower gluconeogenic rate with lactate (5.1 +/- 0.3 vs. 7.2 +/- 0.3 mumol.min-1.g dry cells-1, P < 0.001) but not with dihydroxyacetone (9.1 +/- 0.3 vs. 9.4 +/- 0.4 mumol.min-1.g dry cells-1), suggesting involvement of the phosphoenolpyruvate-pyruvate cycle. Experiments with perifused hepatocytes from hypoxic and control rats showed a single relationship between phosphoenolpyruvate and glucose flux (JGlc) but two different curves when cytosolic oxalacetate was plotted against JGlc. The decreased phosphoenolpyruvate carboxykinase (PEPCK) activity in the hypoxic group (9.0 +/- 0.9 vs. 16.2 +/- 1.9 nmol.min-1.mg protein-1, P < 001) without change in the Michaelis constant further settled the involvement of this step. The significant decrease in PEPCK mRNA levels in livers from hypoxic rats led us to propose that in vivo hypoxic exposure inhibits gluconeogenesis at the PEPCK level by decreasing PEPCK gene transcription.
No file

Dates and versions

inserm-00390250 , version 1 (01-06-2009)

Identifiers

  • HAL Id : inserm-00390250 , version 1
  • PUBMED : 7762652

Cite

Christophe M. Pison, Christiane Chauvin, Eric M. Fontaine, Franoise Catelloni, Christiane M. Keriel, et al.. Mechanism of gluconeogenesis inhibition in rat hepatocytes isolated after in vivo hypoxia.. American Journal of Physiology, 1995, 268 (5 Pt 1), pp.E965-73. ⟨inserm-00390250⟩

Collections

INSERM UGA
60 View
0 Download

Altmetric

Share

Gmail Facebook X LinkedIn More