title: Chronic exposure to uranium leads to iron accumulation in rat kidney cells.
abstract: After it is incorporated into the body, uranium accumulates in bone and kidney and is a nephrotoxin. Although acute or short-term uranium exposures are well documented, there is a lack of information about the effects of chronic exposure to low levels of uranium on both occupationally exposed people and the general public. The objective of this study was to identify the distribution and chemical form of uranium in kidneys of rats chronically exposed to uranium in drinking water (40 mg uranium liter(-1)). Rats were killed humanely 6, 9, 12 and 18 months after the beginning of exposure. Kidneys were dissected out and prepared for optical and electron microscope analysis and energy dispersive X-ray (XEDS) or electron energy loss spectrometry (EELS). Microscopic analysis showed that proximal tubule cells from contaminated rats had increased numbers of vesicles containing dense granular inclusions. These inclusions were composed of clusters of small granules and increased in number with the exposure duration. Using XEDS and EELS, these characteristic granules were identified as iron oxides. Uranium was found to be present as a trace element but was never associated with the iron granules. These results suggested that the mechanisms of iron homeostasis in kidney could be affected by chronic uranium exposure.
authors: Institut de Radioprotection et de Sûreté Nucléaire, DRPH/SRBE, Laboratoire de Radiotoxicologie Expérimentale, Pierrelatte, France. marie.claraz@irsn.fr
authors: Marie
authors: M
authors: Donnadieu-Claraz
authors: Mathilde
authors: M
authors: Bonnehorgne
authors: Bernadette
authors: B
authors: Dhieux
authors: Christophe
authors: C
authors: Maubert
authors: Marie
authors: M
authors: Cheynet
authors: François
authors: F
authors: Paquet
authors: Patrick
authors: P
authors: Gourmelon
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005290:Ferric Compounds / Q000378:metabolism*; D007668:Kidney / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008657:Metabolic Clearance Rate / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution; D014501:Uranium / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000652:urine*; D014875:Water Pollutants, Radioactive / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D005290:Ferric Compounds; D014875:Water Pollutants, Radioactive; C000499:ferric oxide; D014501:Uranium