Orotic acid excretion and arginine metabolism | 食品添加物合法業者資訊網

由MEBrosnan著作·2007·被引用66次—Theurinaryexcretionoforoticacid,anintermediateinthepyrimidinebiosyntheticpathway,ismarkedlyincreasedinmanyinbornerrorsoftheureacycle ...

The urinary excretion of orotic acid, an intermediate in the pyrimidine biosynthetic pathway, is markedly increased in many inborn errors of the urea cycle and in a number of other disorders involving arginine metabolism. Carbamoyl phosphate, which accumulates within hepatic mitochondria in patients with ornithine transcarbamoylase deficiency, can diffuse to the cytosol and enter the pyrimidine pathway, resulting in greatly increased orotic acid production and excretion. This orotic aciduria also occurs in inborn errors of the mitochondrial ornithine/citrulline transporter, arginase, argininosuccinate synthetase, and argininosuccinate lyase. Increased orotic acid excretion is also found in a number of hypoargininemic states, such as lysinuric protein intolerance. However, orotic aciduria should not be used uncritically as an index of arginine deficiency because it is found in patients with arginase deficiency who exhibit hypera...