Studies on the intracellular composition of livers from rats fed 2-acetylaminofluorene.

Price and his associates (17, 18, 19) found al terations in the amounts of protein, nucleic acids, and riboflavin in various fractions of the liver during the induction of liver tumors by a series of aminoazo dyes of widely different carcinogenic ac tivities. The changes induced by the more active carcinogens made the composition of the liver ap proach that of the tumors induced by the parent compound, 4-dimethylaminoazobenzene (20). Griffin et al. (6) determined the effect of 2acetylaminofluorene (AAF) on the composition of rat liver during a prolonged period of feeding the compound. They found that the concentrations of total nitrogen, riboflavin, and pentosenucleic acid (PNA) decreased toward those found in the tu mors induced by this carcinogen, while the concen tration of desoxypentosenucleic acid (DNA) per gram of liver remained nearly normal. In the present study, the intracellular changes in the content of nucleic acids, riboflavin, and pro tein-nitrogen were followed during hepatic carcinogenesis by AAF by analysis of the fractions obtained by differential centrifugation of liver homogenates.