ZN-65 UPTAKE BY LIVER OF RATS FED 3'-METHYL-DIMETHYLAMINOAZOBENZENE

The uptake of Zn-65, determined by gamma-counting and also by autoradi ography, significantly increased with the increasing level of metallot hionein in liver 4 weeks after the start of feeding a diet containing 3'-methyl-dimethylaminoazobenzene (3'-Me-DAB), at which time the serum gamma-glutamyl transpeptidase activity was not yet significantly elev ated. At this time, furthermore, hepatic uptake of Ga-67-citrate did n ot increase and that of Tc-99m-Sn-colloid decreased in 3'-Me-DAB-fed r ats. These results suggest that a short-life gamma-emitting isotope su ch as Zn-69m may be useful for the detection at the early stage of hep atic carcinogenesis.