Vanadate treatment increases the activity of glycolytic enzymes and raises fructose 2,6-bisphosphate concentration in hearts from diabetic rats.

The present study examined the effect of vanadate on the activity of key enzymes of glycolysis and the level of fructose 2,6-bisphosphate (F-2, 6-P2) in the hearts of diabetic rats. A 20% decrease in the total hexokinase activity and 66% decrease in the type II isoenzyme was found in diabetic rat hearts. Vanadate treatment doubled the activity of type II hexokinase. Pyruvate kinase and phosphofructokinase 1 activity was reduced by 20% in diabetes, vanadate treatment restored the activity of the enzymes to normal. A 43% decrease in the cardiac F-2, 6-P2 level was found in diabetes of four weeks duration. A significant inverse correlation between blood glucose of experimental animals and the level of heart F-2, 6-P2 was observed. Vanadate treatment doubled the amount of F-2, 6-P2 in diabetic rat hearts.