Deprivation of Dietary Nucleotides Results in a Transient Decrease in Acid-Soluble Nucleotides and RNA Concentration in Rat Liver

This study examines the contribution of dietary nucleotides to liver nucleotide pools in rats. Liver acid-soluble nucleotides, DNA and RNA concentrations were monitored in two groups of rats fed either a diet supplemented with nucleotides or a diet free of nucleotides for 3 wk. Significantly lower concentrations of ATP, ADP, GTP and CDP as well as of RNA were found after 1 wk in the rats fed a nucleotide-free diet compared with those fed the nucleotide-supplemented diet; concentrations remained lower after 2 wk except for ATP and ADP. No changes over time were observed in the rats fed the nucleotide-supplemented diet. Between wk 2 and 3 an increase in both acid-soluble nucleotides and RNA was observed in the rats fed the nucleotide-free diet, reaching the values found in the rats fed the nucleotide-supplemented diet. These findings, which indicate that dietary nucleotides are utilized at least in part by the liver to maintain the cell nucleotide pools and that diets devoid of nucleotides affect hepatic nucleotide metabolism and RNA, support the hypothesis that liver nucleotide metabolism is modulated by the availability of dietary nucleotides.