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The Journal of Clinical Investigation Oct 1974A detailed investigation of the purification of pyrrole-2-carboxylate (PCA) from human and rat urine indicates that previously reported mean values overestimate the...
A detailed investigation of the purification of pyrrole-2-carboxylate (PCA) from human and rat urine indicates that previously reported mean values overestimate the correct quantity of free PCA by a factor of approximately three for rat urine and approximately five for human urine. Although several criteria of purity were satisfied by a previous method, pyrrole-reactive impurities were still present in the final fractions. These impurities are separated from PCA by chromatography through an amino acid analyzer ion-exchange resin. With the corrected method, normal human values for endogenous urinary PCA in 16 individuals averaged 0.51 mumol/day, with a range of 0.20-1.3 mumol and a SD of 0.31 mumol. The probable source of human PCA is free hydroxy-L-proline, as inferred from the high value for PCA in the urine of a subject with hereditary hydroxyprolinemia, and from the threeto eightfold elevation in PCA excretion by two normal subjects after a large oral load of hydroxyl-L-proline. Subcutaneous administration of [2-(14)C]PCA to a single human subject indicated almost complete conversion of the exogenous compound to derivatives, which are largely excreted in the urine. Data are discussed suggesting that much or all of the PCA in human urine may be formed in urine from a labile precursor, presumably Delta(1)-pyrroline-4-hydroxy-2-carboxylate.
Topics: Adolescent; Adult; Amino Acid Metabolism, Inborn Errors; Animals; Carbon Radioisotopes; Carboxylic Acids; Chromatography, Ion Exchange; Female; Humans; Hydroxyproline; Male; Middle Aged; Proline; Pyrroles; Rats; Tritium
PubMed: 4430715
DOI: 10.1172/JCI107821 -
Archives of Disease in Childhood Jun 1980A 6th case of hydroxyprolinaemia is described. The response to an oral hydroxyproline load failed to demonstrate an abnormal response in a presumed heterozygote. The...
A 6th case of hydroxyprolinaemia is described. The response to an oral hydroxyproline load failed to demonstrate an abnormal response in a presumed heterozygote. The infant is developing normally at age 36 months and we agree with others that this aminoacidaemia is benign.
Topics: Amino Acid Metabolism, Inborn Errors; Growth; Humans; Hydroxyproline; Infant; Male
PubMed: 7436493
DOI: 10.1136/adc.55.6.484