Arterial oxygen partial pressures reduce the insulin-dependent induction of the perivenously located glucokinase in rat hepatocyte cultures: Mimicry of arterial oxygen pressures by H2O2

摘要

Liver glucokinase (GK) is localized predominantly in the perivenous zone. GK mRNA was induced by insulin maximally under venous O-2 partial pressure (pO(2)) and only half-maximally under arterial pO(2). CoCl2 and desferrioxamine mimicked venous pO(2) and enhanced the insulin-dependent induction of GK mRNA under arterial pO(2). H2O2 mimicked arterial pO(2) and reduced insulin-induced GK mRNA under venous pO(2) to the lower arterial levels. Thus the zonal O-2 gradient in liver seems to have a key role in the heterogenous expression of the GK gene.