Effects of Allopurinol and Oxonic Acid on Pyrimidine Metabolism in the Pig
Pigs given allopurinol showed an increase in urinary orotic acid and orotidine excretion from a mean of 5 mg to a mean of 50 mg/24 hours. Although the dose of allopurinol was constant the levels of orotic acid and orotidine fell gradually from their initial peak. When the drug was stopped levels returned rapidly to normal. These results are similar to those obtained in rat and man (1), where this effect has been attributed to inhibition of the enzyme orotidylic decarboxylase (2).