title: Biochemical and histopathological responses of Wistar rats to oral intake of microcystins and cyanobacterial biomass.
abstract: OBJECTIVE
  Cyanobacteria are producers of potent and environmentally abundant microcystins, representing an emerging global health issue. In the present study, we investigated the impact of pure microcystins and cyanobacterial biomass on laboratory rats (Wistar albino rats, males, 30 days old) under different exposure scenarios.
  
  
  METHODS
  The rats were fed diets containing fish meat with microcystins in various concentrations and forms (cyanobacterial biomass and isolated microcystins) for 28 days.
  
  
  RESULTS
  Although considerable amounts of microcystins (MCs) were administered to the rats, all levels of MCs in the liver were close to the detection limit (3-5 ng/g fresh weight) using liquid chromatography - tandem mass spectrometry. Only rats exposed to cyanobacterial biomass had clearly higher hepatic and splenic somatic indexes while markers of oxidative stress (glutathione-S-transferase, glutathione reductase, lipid peroxidatio) were significantly increased in the group exposed to the high dose of MCs. Most of the analysed biochemical parameters did not show clear differences among groups. Levels of bilirubin and lipases were significantly increased only after exposure to cyanobacterial biomass and MCs, respectively. Considering microscopic findings in the liver, kidney, thymus, spleen and brain, histopathology was dominated by alterations in the hepatic parenchyma and renal cortical tubular system.
  
  
  CONCLUSIONS
  The present study demonstrates that oral exposure to MCs and cyanobacterial biomass may induce biochemical and detoxification responses associated with damage to liver and kidneys and in the laboratory rat.
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University - Faculty of Science Brno, Czech Republic. adamovsky@recetox.muni.cz.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Adamovsky
authors.affiliation: Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Palikova
authors.affiliation: Veterinary Research Institute, Brno, Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Ondrackova
authors.affiliation: Department of Ecophysiology and Aquaculture, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Zikova
authors.affiliation: Department of Fishery and Hydrobiology, Faculty of Agronomy, Mendel University, Brno, Czech Republic.
authors.forename: Radovan
authors.initials: R
authors.lastname: Kopp
authors.affiliation: Department of Fishery and Hydrobiology, Faculty of Agronomy, Mendel University, Brno, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Mares
authors.affiliation: Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Pikula
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University - Faculty of Science Brno, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Paskerova
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University - Faculty of Science Brno, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Kohoutek
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University - Faculty of Science Brno, Czech Republic.
authors.forename: Ludek
authors.initials: L
authors.lastname: Blaha
mesh_terms: D000818:Animals; D002273:Carcinogens / Q000633:toxicity*; D000458:Cyanobacteria / Q000737:chemistry*; D020387:Food Chain; D007668:Kidney / Q000187:drug effects* / Q000473:pathology; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008297:Male; D052998:Microcystins / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000187:drug effects* / Q000473:pathology
chemical_list: D002273:Carcinogens; D052998:Microcystins