Utilization of Fructose, Galactose and Glucose by Diabetic Rabbits

Abstract

Fructose, galactose and glucose were fed to normal and alloxan-diabetic rabbits. Some of the animals received an intravenous injection of dihydroergotamine prior to the feeding of fructose. The levels of these sugars and true glucose were estimated in samples of blood collected for varying periods after the administration of these sugars. These sugars were also determined in the urine of the animals. Fructose and galactose were removed from the blood very rapidly in both the normal and diabetic rabbits and insignificant amounts of these sugars appeared in the urine. There was a considerable increase in the true blood glucose level and increased amount of glucose appeared in the urine of diabetic rabbits after fructose or galactose was fed. Dihydroergotamine partly suppressed this hyperglycemia after the administration of fructose. Alloxan-diabetic rabbits in spite of their normal ability to initiate the metabolism of fructose and galactose, either transform a considerable amount of these sugars into glucose or spare the utilization of blood glucose. Superiority of these sugars as alternate source of energy is questioned.