Extrahepatic sites of metabolism of N-nitrosopyrrolidine in mice and rats.

1. By the use of whole-body autoradiography, the localization of N-nitroso[14C]pyrrolidine and its metabolites was demonstrated in the tissues of C57B1-mice and Sprague-Dawley rats. 2. On the basis of the autoradiographic data, tissues were selected and tested for their ability to metabolize N-nitroso[14C]pyrrolidinie to 14CO2 and tissue-bound metabolites. 3. The results indicated that only few tissues had a marked ability to degrade N-nitrosopyrrolidine. These were the liver and the nasal mucosa in both species, the tracheobronchial mucosa in mice, and to a lower extent the kidneys in both species.