1969 Volume 18 Issue 6 Pages 212-215
Since the earliest days of nuclear medicine, it has been a hope of investigators in this field that new tumor localizing agent for radioisotope image could be found. Several agents of this kind have been proposed. But the use of these agents for routine diagnosis is not satisfactory.
The authors synthesized 5-iodouracil-131I (5-131IU) and investigated its distribution in tissues of mice. The results were as follows;
1) The synthesis was performed in newly devised glass apparatus to reduce the γ-ray exposure during the chemical procedure.
2) The thin layer radiochromatogram indicated that the iodination was completed in one hour after reaction mixture. Specific activity of 5-131IU was 1 mCi/mg (600 μCi/ml), and the yield of 5-131IU was 60%. The autoradiolysis was 10% in 30 days.
3) Stomach and kidney had the special affinity to 5-131IU, and the tumor implanted in mice (Ehrlich tumor) incorporated in relatively high ratio in 1.5-2.0 hours after intraperitoneal injection. But the microautoradiographic study showed no evidence of incorporation of 5-131IU in tumor cells.
4) The thin layer radiochromatogram revealed that the radioactive substance in gastric tissue (1.5 hours after injection) was no longer in the form of 5-131IU.
