Cellular localization of intratracheally administered 210PO in the hamster lung using autoradiography of thin sections from plastic embedded tissue

The cellular localization of polonium-210 (210Po), given intratracheally either alone in saline or adsorbed onto ferric oxide carrier particles, has been studied using autoradiography of 1 μm sections from glycol methacrylate embedded tissue. Within the first week after instillation, 210Po administered in saline was localized in the alveolar region primarily in type 1 epithelial--endothelial cells and macrophages, and to a lesser extent in great alveolar cells. In the larger airways, 210Po was localized primarily in ciliated and Clara cells. Following administration adsorbed onto ferric oxide carrier particles, 210Po was found primarily in alveolar macrophages surrounding respiratory bronchioles and alveolar ducts. 210Po localization in relation to the pathologic changes reported in the previous paper (LISCO et al., these Proceedings) is presented here. At later times, significant numbers of alpha tracks were found in the lesions, but they were almost entirely absent in areas of the lung which appeared to be normal