STUDIES ON DIHYDROTHIAMINE : (II) THE BIOLOGICAL ACTIVTY OF DIHYDROTHIAMINE (1)

Abstract

The daily subcutaneous injections of 410 μg dihydrothiamine (DHB_1) to albino rats on thiamine-deficient diet for 14 days provided no gain of the weights : The response curves are nearly same as those of the thiamine-deficient group, while the daily doses of 500μg (equimolecular to 410μg of DHB_1) of thiamine-HCl gave the average weekly gain of 11g. Estimation of thiamine contents of the rats reveals that the DHB_1 group contains far less thiamine than the thiamine group and nearly same or a little more thiamine than the thiamine-deficient group in liver, kidney, heart and intestine. Thus DHB_1 has proved to have neither thiamine activity of promoting rat-growth nor possibility of biochemical conversion into thiamine in vivo.