Influence of dietary zinc deficiency and parenteral zinc on rat liver fructose 1,6-bisphosphatase activity.

Fructose 1,6-bisphosphatase activity in liver of rats fed a zinc deficient diet was decreased to 60% of that in zinc adequate controls. Activity in the zinc deprived rats was not restored to control values by in vitro addition of EDTA. When a physiological dose of zinc was tube fed to the depleted rats, activity increased approximately 150% within 0.5 hr of the dose, and by 1 hr plateaued to a level seen in zinc adequate controls. A significant transient decrease in activity occurred following an intraperitoneal zinc load. This is reversible by in vitro addition of EDTA. These results suggest that rat liver fructose 1,6-bisphosphatase activity is highly sensitive to zinc in vivo as has been demonstrated in vitro.