Effect of Glucose and Fructose in the Protein-repletion Diet Fed after Protein-depletion on Some Blood Constituents of Rats

Percentages of carbohydrates absorbed for 1 day-feeding of protein-repletion diet containing either glucose (glucose-group) or fructose (fructose group) after protein-depletion for 14 days were entirely the same. Some changes in blood constituents of the glucose group and the fructose group were studied. There were no detectable fluctuations in glucose concentration in blood of both groups for varying periods of time of feeding the protein-repletion diet. Whereas, pronounced elevation in fructose concentration in blood was observed for the fructose group. Its values increased for 9hr after feeding the protein-repletion diet containing fructose and then decreased gradually. However, fructose concentration in blood of the glucose group was low. The total carbohydrate concentration (glucose and fructose) in blood of the fructose group increased continuously for 6 hr after feeding the protein-repletion diet and then stayed constant. The total carbohydrate concentration of the fructose group was significantly higher than that of the glucose group except 72 hr-feeding. When the protein-repletion diet was given for 3 days, both liver weight and liver lipid content of the glucose group were significantly lower than those of the fructose group. Allantoin concentration in blood of the fructose group was significantly higher than that of the glucose group. Similarly it was also observed that uric acid level in the serum of the fructose group tended to be higher than that of the glucose group.