Ultrastructural Investigation of Lead-Induced Intranuclear Inclusion Bodies in Mice

Abstract

By means of optical and electron microscopy and by atomic absorption spectrophotometry in a graphite chamber, this study evaluated the effect of temperature (22-35 degrees C) on lesions in the kidney, liver, and brain, and on concentrations of lead caused by the administration of 2 and 5 mg/kg/IP of lead acetate to Swiss mice. The most pronounced effects were observed in the kidney and in groups of animals receiving the highest doses (5 mg/kg at 22 and 35 degrees C). These effects consisted of significantly higher (p < .05) lead concentrations in the tissues, a significant decrease (p < .05) in kidney weights, and progressive kidney atrophy and fibrosis with, at the ultrastructural level, constant intranuclear inclusions, which were also observed in the cytoplasm of renal and endothelial cells.

Intranuclear Inclusions in Renal Tubular Epithelium in Immunodeficient Mice Stain with Antibodies for Bovine Papillomavirus Type 1 L1 Protein

“…In our study, it seems unlikely that these agents were involved in the pathogenesis of the inclusion bodies, as the mice had no known exposure to them, the mice were kept in specific pathogen free conditions and most of these agents are not known for producing intranuclear inclusion bodies. Lead exposure, on the other hand, is known to produce intranuclear and intracytoplasmic inclusions in the proximal convoluted tubules of many animal species [ 32 ], however, the ultrastructural investigations performed in this study showed that affected nuclei were filled with an electron lucent material, and this is inconsistent with lead inclusions that have an electron dense central core surrounded by a zone of fibrillar structures. Nonetheless, the possibility remains that an unknown environmental insult may have been associated with the formation of renal tubular intranuclear inclusions in these mice.…”