[Dynamics of changes in the rat thymus gland as affected by intratracheal administration of 238Pu]

A study was made of the effect of intratracheal administration of 238Pu nitrate on rat thymus. Incorporation of an acutely effective dose of the radionuclide (740 kBq X kg-1) induced damages to all thymus structures. The optimal blastomogenic 238Pu amount (92.5 kBq X kg-1) administered during the chronic period of the disease caused complex changes of atrophic, hyper- and neoplastic nature the lymphoid component of the thymus being primarily damaged.