[Plutonium localization in the nuclear fraction of lung cells]

Pu localization in the nuclear fraction isolated from rat pulmonary tissue cells was studied by histoautoradiography. It was found out that 24 h after intratracheal administration of Pu, 93.8% of the radionuclide (of the total number of tracks) were bound with nuclei. It was also shown that 64.8% of Pu were fixed by large nuclei, 42.2% by small nuclei. Pu content in nuclei varied within broad ranges: from single tracks up to high density "stellae".