The Course of Vitamin B_1 Metabolism in Man as Indicated by the Use of Radioactive Sulfur. A New Synthesis of 4-Methyl-5-β-Hudroxyethyl-Thiazole, and a Demonstration of the Use of Anti-Coincidence Method in Radioactivity Determinations

[摘要] Thiamin synthesized from radiosulfur S³⁵ was injectedintramuscularly in two series of experiments, using a human subjecton a normal and a B₁-free diet. Determinations of the free B₁ (bythe thiochrome method) in the uring, the radiosulfur in the inorganic,ethereal, and neutral fractions of the urine, and the total radiosulfurin the feces were made. Rapid destruction of injected thiaminwas indicated in both experiments by the appearance of radiosulfurin the inorganic fraction of the urine. Rapid interaction of theinjected material with that pre-existing in the tissues was indicatedby the appearance of free thiamin in the urine, without correspondingactive sulfur. Additional destruction of thiamin was indicated byan excess of the neutral radiosulfur activity over the free B₁ afterthe injections were stopped. After 36 days of the B₁-free diet theinjection of 8 mg. over a period of 3 days resulted in the excretionof 0.8 mg. of pre-existing thiamin. On the normal diet the injection of 63 mg. over a period of 4 days resulted in the excretion of 16 mg.of pre-existing thiamin.

[发布机构] University:California Institute of Technology;Department:Biology

[关键词] Biology