Abstract
In the previous test, we found slight weight gains in some of albino rats at daily doses 50μg of thiothiamine with either cysteine or menadione. The authors estimated the amount of thiamine in the liver of these rats and found that it was less than 6μg per animal ; that is abount 1/4-1/10 of that of animals receiving daily 5μg of thiamine alone, and nearly the same as that of thiamine deficient or thiothiamine given animals (daily 50μg). The homogenate of rat liver was proved to have no ability to convert thiothiamine into thiamine even in the presence of menadione or cysteine : the absorption of oxygen was not increased by shaking liver homogenate with thiothiamine for 1.5-2 hours, compared to the homogenate alone. In these experiments the addition of menadione or cysteine did not stimulate the oxygen absorption. Moreover, after menadione or cysteine was previously given to rats for 4 days, their liver homogenate also indicated no additional oxygen uptake with thiothiamine.
