Uric Acid Metabolism


Nitrogenous compounds are continuously derived from digestion of proteins in ingested food, degradation of nucleic acids, purine salvage pathways, de novo purine biosynthesis, and purine nucleotide interconversion. Nitrogenous waste products are highly toxic; therefore, efficient mechanisms of elimination have evolved, that are optimally suited for the particular class of organism. All animals excrete three main nitrogenous products – ammonia, urea and uric acid – as well as minor nitrogen excretory products.

Keywords: uric acid; ammonia; urea; purines; xanthine; oxidase; xanthinuria; gout; hyperuricemia

Figure 1.

Major pathways of purine metabolism. Highly toxic nitrogenous wastes are produced during purine metabolism. Efficient pathways for elimination of theses toxic wastes have evolved that are optimally suited for the particular class of organism.

Figure 2.

Clinical consequences of altered nucleotide metabolism. Clinical problems associated with nucleotide metabolism in humans are predominantly the result of abnormal catabolism of purine. The clinical consequences of abnormal purine metabolism range from mild to severe and even fatal disorders.



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Further Reading

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Skinner, Kelly A, Parks, Dale A, and Khoo, Nicholas H(Jan 2006) Uric Acid Metabolism. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0003910]