Effect of D-Fructose on the Nucleotide Pool in Liver

Because of the rapid and efficient utilization of D-fructose in the liver, this sugar has been used for intravenous feeding.156 However, ample evidence indicates that rapid infusion of D-fructose causes breakdown of adenine nucleotide, and induces hyperuricemia.259-261 The mechanism of D-fructose-induced hyperuricemia is probably by way of the rapid phosphorylation of D-fructose to D-fructose 1-phosphate (by ketofructokinase) which causes liver depletion of ATP and inorganic phosphate.259,260 When a fasted animal receives an intraperi- 

As both IMP and inorganic phosphate are inhibitors287,288 of 5-0-phosphono-D-ribosylamidotransferase, their increase influences a decrease in the rate of de novo synthesis of uric acid.287 D-Fructose 

D-Fructose can cause structural alterations of liver in 10 to 90 minutes after intraperitoneal injection. Dense plaques appear in 20% of the liver nucleoli, and the plaques become more prominent in 3 hours. However, a similar change is also seen in the same number of nucleoli when D-glucose is given.270 Administration of D-fructose by intravenous perfusion induces ultrastructural alterations in smooth membrane, proliferations, cytolysome formation, and hyaloplasmic rarefaction. However, ATP content must decrease by 50% or more before gross, structural changes are observed.270 

Effect of d-Fructose on the Energy Metabolism of Intestinal, Epithelial Cells 

Intraluminal administration of D-fructose has a negligible effect on the ATP content of liver, although, as described earlier, an intrave- 

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