抄録
Turnover of riboflavin in the liver of mouse was studied. When 80μg of riboflavin-^<14>C was administered orally to a mouse for a day, the exchange of non-labeled flavins originally existed in the liver for the administered one was almost completed in 15 days. By increasing the amount of administered riboflavin-^<14>C, a rapid exchange of flavin in the liver was attained. The decreasing of the amount of dietary protein did not change the exchange rate. After the flavin in the liver of mouse was completely exchanged for the labeld one, non-labeled riboflavin (80μg/day/mouse) was administered, the biological half life of flavin was found at 7-8 days after the administration of non-labeled riboflavin, whereas it was prolonged markedly when non-labeled riboflavin was not administered.
