The Metabolism ofS-Carboxyalkylcysteines in Man

Abstract
1. The ingestion of S-(2-carboxy-1-methylethyl)-, S-(2-carboxy-1-methyl-propyl)-, S-(1-carboxy-2-methylpropyl)- and S-(2-carboxyethyr)-L-cysteine by man was followed by the excretion in the urine of the unchanged amino acid and the N-acetylated compound. 2. In the rat the fraction of S-(2-carboxy-1-methylethyl)-L-[U-14C]cysteine acetylated increased as the dose level decreased. 3. The significance of these results for the excretion of S-carboxyalkyl-cysteines in man is discussed.