Autoradiographic Study of the Distribution of Bound Radioactivity in the Respiratory Tract of Syrian Hamsters Given N-[³H]Nitrosodiethylamine¹

Adult Syrian golden hamsters received a single intragastric dose of N-[³H]nitrosodiethylamine. Their tracheas, extrapulmonary stem bronchi, and lungs were processed for high-resolution light-microscopic autoradiography to monitor the distribution of bound radioactivity. In the trachea and extrapulmonary stem bronchi, mucous cells contained the most bound radioactivity, while in the lobar and segmental bronchi and bronchioles, Clara cells were the major site of binding. In conjunction with earlier conducted studies on the pathogenesis of N-[³H]nitrosodiethylamine-induced respiratory tract tumors, these findings indicate that metabolic competence and a preexisting capacity for proliferation are important factors in determining the target cell types of this compound.