The estimation of histidine in urine and its excretion by normal and pregnant women

Abstract

Histidine in urine was detd. colorimetrically with the Knoop reaction in acid soln. Details are given for the control of factors influencing this reaction. The 24 hr. urinary histidine excretion of 38 normal [female] [female] at weekly intervals during a complete menstrual cycle was detd. No significant trends or correlation with gonadotrophic hormone activity were observed. The excretion during the course of 2 normal pregnancies was detd. In the first case there was a peak in the excretion at the 5th mo. and the excretion was at a higher level than in the 2d mo. The diet of the 2d patient showed a low protein and Fe intake.