INHIBITORY EFFECT OF DIETARY IRON-DEFICIENCY ON THE INDUCTION OF PUTATIVE PRENEOPLASTIC FOCI IN RAT-LIVER INITIATED WITH DIETHYLNITROSAMINE AND PROMOTED BY PHENOBARBITAL

The effects of dietary iron deficiency on induction of putative preneoplastic, gamma-glutamyltransferase (GGT)-positive hepatocyte focal lesions in the liver of rats treated with diethylnitrosamine (DEN) followed by phenobarbital (PB) were investigated. Male Fischer 344 rats of 4 weeks old were placed on an iron deficient (ID) diet containing less than 5 p.p.m. of iron or an iron supplemented (IS) diet containing 180 p.p.m. of iron throughout experimental period of 12 weeks. Both groups of rats were administered 200 mg kg-1 body weight of DEN by a single intraperitoneal injection at Week 4 followed by PB mixed into each diet at a concentration of 0.05% from Week 6 to the final sacrifice at Week 12 when induction of GGT-positive foci was quantitatively analysed. On the ID and IS diets, respective numbers of GGT-positive foci were 6.3 and 14.2 cm-2. The sizes of foci were not altered by the iron content of the diet. The present results indicate that iron plays a role in the development of preneoplastic foci in the livers of rats initiated with DEN and promoted by PB especially in the initiation phase.