Studies of some indole compounds isolated from the urine of a mentally retarded child.

During the investigation of the urine of a mentally retarded child, a number of indole compounds were isolated. Gel filtration of the native urine gave three chief fractions. phatase fraction of blood had properties unlike that of the red blood cell enzyme and Extraction methods available for the isolation of the abnormal indoles in large amounts resulted in irreversible structural changes, probably detachment of the carboxy groups, with loss of electrophoretic mobility, changes of chromatographic properties, and decreased water solubility. It is presumed that the presence of the abnormal indoles isolated is the result of disturbed metabolism of the aromatic amino acids.