Induction of Hepatic and Intestinal Flavokinase After Oral Administration of Riboflavin to Riboflavin-Deficient Rats

Abstract

Use of [14C]riboflavin to assay flavokinase of rat liver and intestine yields apparent activities which are higher than those previously reported. Rats fed a riboflavin-deficient diet for 50 days after weaning have lower intestinal and hepatic flavokinase activities than animals fed a complete diet. Within 6-8 hr after oral administration of 50 .mu.g of riboflavin to the deficient rat, the flavokinase levels of both organs have nearly doubled. Hence, the riboflavin-deficient rat rapidly recovers the capacity to phosphorylate riboflavin after the vitamin is reintroduced into the diet.