Abstract
Thiamine propyl disulfide (TPD) or dicarbethoxythiamine (DCET) can penetrate into bovine erythrocytes either in whole blood or in suspension of erythrocytes in Krebs-Ringer phosphate buffer ; TPD, when added to a suspension of erythrocytes, was quickly and completely absorbed by the erythrocytes but DCET was only partly and gradually absorbed by them. When applied to whole blood, TPD was incompletely absorbed by erythrocytes, while DCET was absorbed by them to nearly the same percentage as in the case of a suspension. DCET in erythrocytes was washed out by repeated shaking with saline solutions, whereas no washing out of the erythrocytes which contained TPD, by saline was observed. DCET is rather stable either in erythrocytes or in serum ; slow reduction of DCET to thiamine was demonstrated by both paper partition chromatography and microbiologiaal assay using Kloeckera apiculata. TPD was quickly reduced to thiamine both by serum and by hemolyzed erythrocytes. The difference between TPD and DCET in their stability in blood systems is partly responsible for easy or slow penetration into erythrocytes.
