MACROAUTORADIOGRAPHIC ASSAYS OF ^<14>C-LABELED 4-NITROQUINOLINE 1-OXIDE IN ADULT AND FETAL MICE

Abstract

The distribution of radioactivity from ^<14>C-labeled 4-nitroquinoline 1-oxide (4-NQO), which is a known transplacental carcinogen, was observed by macroautoradiography in adult and pregnant mice. Radioactive substances derived from the labeled carcinogen passed across the placenta and were distributed intensely in the kidneys, urinary bladder and intestinal tract of the fetus near term and uniformly in all organs of the fetus on the 16th day of gestation. This indicates that fetus near term has an ability to metabolize this carcinogen. No significant differences in specific radioactivity was noted between tissues that were susceptible or resistant to this carcinogen.