To evaluate the time-course and reversibility of toxicity of a low-osmolar and an iso-osmolar radiographic contrast medium on renal tubular cell cultures.
Materials and Methods:
LLC-PK1-cells were incubated with iomeprol, iodixanol, and mannitol (4.7–75 mg I/mL, 2–24 hours). Metabolic activity was assessed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide-(MTT) assay.
Iomeprol and iodixanol induced a time- and dose-dependent inhibition of MTT conversion (75%–19% and 70%–23% of control for iomeprol and iodixanol, respectively, at concentrations ranging from 4.7 to 75 mg I/mL after an incubation time of 2 hours and 64%–14% and 65%–12% of control after 24 hours). The mannitol induced inhibition of the MTT conversion was significantly weaker than that induced by iomeprol (99%–47% of control at concentrations corresponding to 4.7–75 mg I/mL after an incubation time of 24 hours, P < 0.001). After 24 hours incubation with iomeprol, iodixanol, or mannitol and a recovery time of 2 hours after removal of the test-solutions, there was only a small inhibition of MTT-conversion (89%, 88%, and 95% of control at 75 mg I/mL).
Contrast medium induced cytotoxicity consisted of a reversible part and an irreversible part. There was no difference in cytotoxicity between iomeprol and iodixanol over a broad range of concentrations and incubation-times.