[The preventive effect of calcium-channel blockers (nifedipine, verapamil) on the tubular toxicity of radiographic contrast media (Verografin, Hexabrix)].

The authors investigated the nephrotoxic effect of the high-osmolar X-ray contrast medium (diatrizoate) and low-osmolar contrast medium (ioxaglate) and attempted to influence it by Ca channel blockers (nifedipine and verapamil). The criterium of tubular toxicity was the monitoring of urine wastes of tubular enzymes--alkaline phosphatase (ALP), gamma glutamyl transferase (GMT) and N-acetyl-beta-D-glucosaminidase (NAG). As criterium of glomerular functions he authors assessed the endogenous creatinine clearance. The experiments were made on outbred male rats Wistar strain for a total of 7 days following administration of the contrast medium. In animals to whom contrast medium only was administered a significant increase of urine waste of the investigated enzymes was observed. Maximum changes were recorded in the excretion of brushborder enzymes. Diatrizoate caused a significantly higher increase of enzymuria than ioxaglate. Administration of Ca channel blockers significantly reduced this rise of enzymuria, but the authors were unable to eliminate this rise completely. There were no statistically significant differences between the action of nifedipine and verapamil.