Human Erythrocyte Phosphoribosylpyrophosphate Content and “Generation” During a Constant Rate Infusion of Xylitol
Marked increases in serum uric acid concentrations have been observed following rapid intravenous infusions of fructose (2,6). With constant rate intravenous infusions of 0.5 g fructose/kg body weight/hr over 5 hours however we cannot demonstrate remarkable changes in serum uric acid levels (3,4). With the same dose xylitol, with a rate of 0.5 g xylitol/kg body weight/hr, we are able to demonstrate even higher increases in serum uric acid concentrations than with 1.5 g fructose/kg body weight/hr over 5 hours (3,4). This hyperuricemic effect of xylitol could be due in part- comparable to that of fructose- to an increased rate of purine synthesis de novo or an accelerated degradation of purine ribonucleotides. Since intracellular 5-phosphoribosyl-1-pyrophosphate (PRPP) concentration limits purine biosynthesis de novo and is also a substrate in the reutilization pathways for purine bases we assessed PRPP levels and PRPP “generation” in erythrocytes after oral administration and during constant rate infusion of varying xylitol doses.
KeywordsSerum Uric Acid Serum Uric Acid Level Infusion Period Purine Nucleotide Constant Rate Infusion
Unable to display preview. Download preview PDF.
- 7.Sperling, O., Eilam, G., Persky-Brosh, S., and DeVries, A. J. Lab. Clin. Med. 79, 1021 (1972).Google Scholar