Adenosine Deaminase, Nucleoside Phosphorylase and Xanthine Oxidase in Liver Tumours

The tissue fractions now analyzed were those prepared in a previous study (Reid and O'Neal, 1956), to which reference should be made for details of the procedures employed. The fractions were, in general, derived from the livers of albino rats which had been fed 3'-methyl-4-dimethylaminoazobenzene; but one experiment (" 14/7") was carried out with a hepatoma arising in a rat of the "August" strain which had been fed p-dimethylaminophenylazo-2-naphthalene. As indicated in Fig. 1, experimental rats were always studied simultaneously with controls which had been fed on the same diet but with omission of the carcinogen. The "pre-cancerous liver" studied in some experiments was obtained from rats which had been fed the azo-dye for only 4 weeks. Tissue from rats which had been fed azo-dye for a prolonged period was classified into the following categories, with the kind collaboration of Dr. R. Daoust: hepatoma with little