Noun: xanthine zantheen
- Crystalline oxidation product of the metabolism of nucleoproteins; precursor of uric acid; found in many organs and in urine
Derived forms: xanthines
Type of: organic compound
A purine base found in most body tissues and fluids,certain plants,and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid,being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine,theobromine,and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland,28th ed) n : a feebly basic compound C5H4N4O2 that occurs esp. in animal or plant tissue, is derived from guanine and hypoxanthine, and yields uric acid on oxidation; also : any of various derivatives of this
- tungstate competitively inhibits the utilization of molybdenum for the formation of xanthine dehydrogenases.
- Xanthines such as caffeine and theobromine are cAMP-phosphodiesterase inhibitors.
- It is caused by a deficiency of the enzyme xanthine oxidase.
- Caffeine, like other xanthines, also acts as a phosphodiesterase inhibitor.
- This pathway also is independent of the enzyme activity of xanthine oxidase.