THE METABOLISM OF PHENYLALANINE-4-C14

Metabolism of Coprostanol-c14 and Cholestanol-4-c14 in Man.

Metabolism of epicholesterol-4-C14 in the rat.

Recent studies on the catabolism of cholesterol-4-Cl4 in the rat have shown that the isot,opic carbon is eliminated from the body almost entirely with the feces and that up to 90 per cent of the fecal Cl4 enters the intestine via the bile. Not more than 10 per cent of the Cl4 is excreted directly through the intestinal wall. Approximately 90 per cent of the Cl4 recovered in bile is in the form ...

Absorption and metabolism of cortisone-4-C14 acetate.

Previous work in this laboratory with steroids labeled with Cl4 (l-10) has been extended to include the present experiments on the absorption and disposition of the radioactive carbon of cortisone-4-U4 acetate’ in the rat. Since the conditions of these experiments, i.e. solvent vehicle, strain and type of animal studied, operative techniques, method of collection of specimens, and Cl4 assay, di...

The metabolism of ascorbic acid-1-C14 and oxalic acid-C14 in the rat.

It is known that oxalic acid is a product of ascorbic acid metabolism in the guinea pig (1) and rat (2), and is formed in man from unidentified precursors (3). Oxalates are also of interest because of their occasional toxicity and unexplained deposition. Ascorbic, dehydroascorbic, and 2,3diketogulonic acids are known to give rise to oxalic and threonic acids in approximately quantitative yields...

Phenylalanine Metabolism: Phenylketonuria

The hydroxylase is a trimer of approximately 150 kDa of identical subunits and is located predominantly in the liver. The enzyme has been mapped to human chromosome 12q22-24.1, where the gene comprises 13 exons extending over 90 kb of genomic DNA. Deletions in the gene are not common. A frequent cause among northern Europeans (~40%) is a G-to-A transition at the 5′ donor splice site in intron 1...