Active Form of Vitamin B₁ in Tissues

Abstract

THOUGH there has been a strong indication since the work of Lohmann and Schuster¹ that the active form of vitamin B₁ in pigeon brain tissue is phosphorylated, the failure to obtain much activity with cocarboxylase in the catatorulin test with “brei” or slices has made it impossible to make a firm decision^2,3. We are now able to report that with the use of two types of finely ground “avitaminous” brain preparations (in presence of fumarate) we can get either (1) a preparation which shows good catatorulin effects with small amounts of cocarboxylase (0.26 max.) and practically no effect with vitamin B₁, or (2) one which still retains some catatorulin effect with large amounts of vitamin B₁ (10 γ) as well as good effects with small amounts of cocarboxylase. Both preparations are rather unstable; the medium vised is as in previous experiments.