Further observations on the effects of lead implantation in rat brains.

Lead pellets were implanted into the forebrains of adult rats. Various cytoplasmic inclusions were found in macrophages, astrocytes, pericytes and microglia. Certain macrophages and reactive astrocytes displayed intranuclear inclusions as well. The hypothalamus, in some of the animals, showed sponginess which proved to be the result of swollen axons.