Effects of Xylitol on Nitrogen, Water and Electrolyte Metabolism in Fasted Rabbits

The effects of xylitol and glucose infused upon nitrogen, water and electrolyte metabolism were comparatively studied in rabbits. During 10 days' fasting, a daily dosis of 40ml/kg of the following solutions was infused for 4 hours. The animals, which were infused with a multiple balanced electrolyte solution, lost 36% of body weight during the fasting, accompanied by net losses of 8 g nitrogen, 160ml water (exclud-ing insensible water loss), 9 mEq sodium, 28 mEq potassium, 2.5 mEq magnesium and 0.2 mEq calcium per kg body weight. The animals were emaciated at the terminal stage and two of six animals died. The animals infused with a 5% glucose solution with balanced electrolyte composition lost 30% of body weight and one of six animals died. The urinary excretions of nitrogen, sodium and calcium in these animals were significantly less than those in animals receiving the electrolyte solution without carbohydrate. More pronounced sparing effects for nitrogen, water, sodium and potassium were found with a 5% xylitol solution with balanced electrolyte composition, while the losses of magnesium and calcium were rather promoted. The decrease of body weight in this group was 24% and none of six animals died. The similar results were also obtained by the infusion of other xylitol solutions with or without electrolyte composition. The sparing effects of glucose were manifested exclusively at the early stage of the fasting, whereas those of xylitol were more pronounced at the late stage when the starvation progressed.