title: Kidney stone distribution caused by melamine and cyanuric acid in rats.
abstract: BACKGROUND
  Melamine (M), which is composed of multi-amine, has been used as a food additive to falsely increase protein contents. Furthermore, cyanuric acid (CA) is a derivative of melamine. It is known that these mixtures can cause renal toxicity.
  
  
  METHODS
  The objective of this study was to investigate the possible target cells during acute renal toxicity of melamine and cyanuric acid (MCA) mixture crystals in vivo. Rats were provided with a lethal dose of MCA (1:1; 400mg/kg) and observed after 0.5, 1, 3, 12, 24, and 48-h intervals.
  
  
  RESULTS
  MCA caused degeneration/necrosis in the proximal tubules starting at 12h and increased at 24 and 48 h. A small number of yellow-green crystals were observed in the dilated distal renal tubules at 48 h post-treatment. Ultrastructurally, pyknosis, mitochondrial vesicles, and cellular swelling were found in the proximal tubular cells at 0.5h. Small needle-like crystals in the cytoplasm and large crystals in the lumen of tubules indicated physical damage to the renal cells.
  
  
  CONCLUSIONS
  These results clearly reveal that in the MCA-induced renal toxicity model, crystals are distributed to both the proximal and distal tubules in rats. The proximal tubular cells may be initially injured and subsequently block the distal tubules with MCA crystals during early acute intoxication.
authors.affiliation: Human Genetic Center, China Medical University Hospital, Taichung, Taiwan; Department of Biomedical Informatics, Asia University, Taichung, Taiwan.
authors.forename: Yng-Tay
authors.initials: YT
authors.lastname: Chen
authors.affiliation: Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Bang-Ping
authors.initials: BP
authors.lastname: Jiann
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Chieh-Hao
authors.initials: CH
authors.lastname: Wu
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Jhaol-Huei
authors.initials: JH
authors.lastname: Wu
authors.affiliation: Department of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Shih-Chieh
authors.initials: SC
authors.lastname: Chang
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Maw-Sheng
authors.initials: MS
authors.lastname: Chien
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Shih-Ling
authors.initials: SL
authors.lastname: Hsuan
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Yi-Lo
authors.initials: YL
authors.lastname: Lin
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Ter-Hsin
authors.initials: TH
authors.lastname: Chen
authors.affiliation: Human Genetic Center, China Medical University Hospital, Taichung, Taiwan; Department of Biomedical Informatics, Asia University, Taichung, Taiwan.
authors.forename: Fuu-Jen
authors.initials: FJ
authors.lastname: Tsai
authors.affiliation: Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan. Electronic address: jwliao@dragon.nchu.edu.tw.
authors.forename: Jiunn-Wang
authors.initials: JW
authors.lastname: Liao
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D007669:Kidney Calculi / Q000139:chemically induced* / Q000473:pathology*; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014227:Triazines / Q000737:chemistry / Q000633:toxicity*
chemical_list: D014227:Triazines; C004632:cyanuric acid; C011907:melamine
keywords: Acute toxicity; Distribution; Melamine and cyanuric acid; Renal crystals