Le dosage de l'histidine dans l'urine par une méthode enzymatique spécifique: Et son application à l'étude de l'excrétion de l'histidine chez la femme normale et la femme enceinte

Abstract

1. 1. In connection with large scale studies of urinary excretion of histidine in non-pregnant and pregnant women, a gazometric method of histidine determination, based on enzymic decarboxylation and manometric measurement of CO 2 evolved, is compared with Moore and Stein's ion-exchange Chromatographic method on Dowcx-50-X 8 columns. Both methods are applied directly to urine. 2. 2. The enzymic decarboxylation procedure is a rapid one and easy to perform. It gives more accurate results than the Chromatographic method on 15 cm Dowex-50-X 8 columns, when the urinary histidine output is low (non-pregnant women). When the histidine excretion in urine is increased, both methods yield the same figure within the limits of less than 5%. 3. 3. The data confirm the authors previous assumptions. In non-pregnant women the daily urinary excretion of histidine is less than 210 mg/24 h under uncontrolled diet conditions: it rises above this maximum as early as two weeks after absence of menstruation.