Author/Editor     Milutinović, Aleksandra; Živin, Marko; Zorc-Pleskovič, Ruda; Sedmak, Bojan; Šuput, Dušan
Title     Nephrotoxic effects of chronic administration of microcystins -LR and -YR
Type     članek
Source     Toxicon
Vol. and No.     Letnik 42
Publication year     2003
Volume     str. 281-8
Language     eng
Abstract     Acute intoxication with MC-LR induces cytoskeletal alterations, apoptosis and necrosis of hepatocytes resulting in intrahepatic hemorrhage. Preliminary results have shown that chronic treatment of rats with intraperitoneal injections of sublethal doses of microcystins MC-LR and MC-YR could induce not only liver, but also kidney injuries. We aimed to investigate whether the induction of the cytoskeletal changes, apoptosis and necrosis could be the mechanisms involved in the injury of kidney cells in the chronic model of microcystin intoxication. Experimental rats were receiving intraperitoneal injections of MC-LR (10 microg/kg) or MC-YR (10 microg/kg) every second day for 8 months, while control rats were receiving only the vehicle. The histopathological investigation revealed collapsed glomeruli with thickened basement membranes and dilated tubuli filled with eosinophilic casts. Rhodamine-phalloidin labeling showed cytoplasmic aggregation and accumulation of fibrilar actin filaments within the epithelial tubular cells. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) showed increased number of TUNEL-positive cells in the kidney cortex and medulla. The pathological changes induced by MC-LR appeared more severe than those induced by MC-YR. The results support the view that at the cellular level, the mechanisms that underly the chronic nephrotoxicity are similar to the mechanisms of the acute hepatotoxicity of microcystins.
Descriptors     KIDNEY
BACTERIAL TOXINS
CYANOBACTERIA
APOPTOSIS
MICROFILAMENTS
RATS
RHODAMINES
PHALLOIDINE
DNA FRAGMENTATION