INTRANUCLEAR DENSE BODIES AFTER METAL INTOXICATION : A REVIEW OF ULTRASTRUCTURAL AND MICROANALYTICAL FINDINGS

: Abnormal intranuclear dense bodies are observed in several varieties of cells after intoxication by four varieties of metals: lead, bismuth, beryllium and neptumium. These inclusions have been studied by two microanalytical methods: Electron probe X-ray microanalysis (EPMA) and ion microscopy. A strong similarity has been observed in the ultrastructure of the dense bodies produced several weeks after beryllium and neptunium intoxication although there exists an important discrepancy between both elements concerning their physical, chemical and physico-chemical characteristics. Furthermore, these dense bodies are observed in the same varieties of cells (tubular proximal cells of kidneys, hepatocytes, pneumocytes). Intranuclear dense bodies produced by lead are also observed in the same types of cells, where they showed similar ultrastructure patterns as beryllium and neptunium inclusions but only after a long period, several years, after a chronic intoxication. The ultrastructure of the dense bodies produced by bismuth are clearly distinct from beryllium, neptunium or lead inclusions. Beryllium, neptunium and lead have been detected by EPMA or ion microscopy in the corresponding dense bodies although the real presence of bismuth remains to be confirmed in the nuclear dense bodies produced by this element.