Thiabendazole (TBZ) nephrotoxicity and recovery in ICR adult mice.

The nephrotoxicity and recovery following administration of thiabendazole (TBZ) were investigated in ICR adult mice. A single oral administration of TBZ (500-2000 mg/kg body wt.) caused a dose-dependent proximal tubular necrosis in the kidney and increase in serum urea nitrogen 24 h after dosing. These changes were marked in mice of high dose groups (1000 or 2000 mg TBZ/kg body wt.). The time course of changes on kidney of mice treated with 1000 or 2000 mg TBZ/kg body weight were examined at 1, 2, 3, 5, 7 or 10 days after dosing. Light microscopy showed necrosis of proximal convoluted tubules from 1 day after dosing. Tubular necrosis was extensive 2 or 3 days after dosing. Partial regeneration from tubular necrosis was seen 3 days after dosing, and substantial regeneration had occurred from 5 days after dosing. Thus, TBZ-induced renal injury was most severe at 2 or 3 days after dosing and was followed by regeneration. Electron microscopy showed swelling of mitochondria in the proximal tubular epithelium at 1 day after dosing. The pathological changes were correlated with the changes in urinalysis, serum urea nitrogen concentration and kidney weight.