The statement is made frequently that uric acid is the end-product of purine metabolism in human beings. The serum level and urinary excretion of this compound have been extensively studied, particularly in patients with diseases such as gout, who show marked increases in urate levels. With the advent of chromatography and radioactive isotopes it has become possible to study some of the purine compounds that give rise to uric acid in the body. Because the purines are essential to life it is not surprising that these newer studies are touching many areas of medicine.
The body purines do not usually occur as free compounds but are ordinarily bound to molecules of sugar and phosphate. This combination of a purine such as adenine, a pentose sugar such as ribose, and phosphate is called a nucleotide. This particular adenine nucleotide is called adenylic acid, or adenosine monophosphate (AMP). More phosphates can be