A Quantitative Chemical Study of the Urinary Excretion of Thiamine by Normal Individuals

Publisher Website
Google Scholar
Abstract
The reaction between thiamine and diazotized p-aminoacetophenone in alkaline solution has been used for the chemical determination of the vitamin in urine. There is a diurnal variation in thiamine excretion due to an appreciable lag in the excretion of the vitamin subsequent to its ingestion as part of the meals. The responses of the standardized subject to both the oral and parenteral administration of a test dose of extra thiamine have indicated that the former procedure is more desirable for evaluating the nutritional status of the individual with respect to this vitamin. The average 24-hour urinary thiamine values of fifteen normal men and nine normal women were 198 and 93 micrograms respectively; 14% of the oral test dose of 5 mg. of extra vitamin were excreted by the men during the first 24-hour period following ingestion and 12% by the women. Variations in these values among the normal subjects were not related to differences in urine volume, in metabolism or in either the vitamin to calorie or thiamine to non-fat calorie ratio of the diet. Urinary thiamine values of normal individuals ingesting a constant diet are reproducible. During the production of an experimental thiamine deficiency the 24-hour urinary values drop precipitously to the avitaminotic range but rise slowly during recovery. The response of the subject to the oral test dose of extra thiamine is governed by the nutritional status of the individual and is independent of the adequacy of the diet consumed at the time of the test. The percentage of the available vitamin, which is excreted in the urine, is a function of how great an excess is present. Subsequent to flooding the organism with thiamine a period of 2 weeks is required to elapse before the urinary values return to the normal basal level. Standards are given for the interpretation of the urinary thiamine values in the diagnosis of thiamine deficiency.

This publication has 15 references indexed in Scilit: