Effects of cysteine and diethylmaleate pretreatments on renal function and response to a nephrotoxicant.

The effects of treatment with either cysteine (2 X 150 mg/kg) or diethylmaleate (0.7 ml/kg) on renal function and response to the nephrotoxicant hexachloro-1,3-butadiene (HCBD) were examined. Cysteine caused oliguria, blocked the polyuric and glucosuric effects of HCBD and attenuated the reduction of urine osmolality. Diethylmaleate (DEM) decreased urine osmolality; further decreases of urine osmolality were not seen after HCBD. DEM pretreatment increased HCBD-induced proteinuria. HCBD-induced elevation of plasma creatinine concentration was not affected by either of the pretreatments whereas the plasma urea nitrogen concentration was greater in the DEM-pretreated group. The latter may represent an effect of DEM on non-filtration handling of urea. The results suggest that cysteine and diethylmaleate each have effects on kidney function which alter the response of the nephron tubule to a subsequently administered toxic agent.