RESUMEN
In the present work, the effect of chronic lead intoxication in two doses [5 mg/kg body weight, as therapeutic dose and 10 mg/kg body weight as sublethal dose] on the ultrastructure of the rat liver was studied. The rats were classified into three groups: one control group [10 rats], experimental group A [20 rats] who received a therapeutic dose of lead acetate orally for six months, and experimental group B [20 rats] who received a sublethal dose of lead acetate orally for six months. Ten rats of both groups A and B were sacrificed one month after the last given dose [recovery rats]. Small slices of the liver of the rats of all groups were processed for electron microscopic examination. The livers of group A rats showed a few pathological changes in the form of proliferation of both rough and smooth endoplasmic reticulum, multiple areas of glycogen depletion with a few lysosomes and fat droplets. The liver of group B rats showed marked pathological changes in both hepatocytes and Van Kuppfer's cells. The cytoplasm of the hepatocytes showed intracytoplasmic vacuoles and a few degenerative granules. The Von Kuppfer's cells showed pale degenerated cytoplasm, intra-cytoplasmic and degenerated electro-dense granules. The recovery animals of group A showed good recovery, while those of group B showed only partial recovery