Factors Influencing Urinary Taurine Excretion by Normal and Mongoloid Subjects

Abstract

The effect of a variety of experimental conditions on urinary taurine excretion by normal and mongoloid subjects was examined. Measurement of taurine was by column chromatography. Habitually “high” and “low” excretors were demonstrably present in both populations. In normal subjects taurine excretion was increased by the ingestion of sulfur amino acid-rich protein, shellfish, cysteamine, hypotaurine, or prednisone; cysteine sulfinic acid and vitamin B6 had no effect; cysteic acid and cysteine had little, if any, effect. While under a taurine load of 4 mg/kg body weight/day, a roughly 3-day periodicity in taurine excretion was noted in both normal and mongoloid subjects. Six weeks of vitamin B6 administration did not correct the subnormal excretion of taurine by mongoloids. Renal tubular reabsorption of taurine appears to be greater in mongoloid low excretors than in high excretors. No correlation between serum and urine taurine values was found. Fasting serum taurine levels varied more widely than had been expected, both intra- and inter-individual, and there is a tendency toward bimodality of these data.