Reduced depression of renal function by iotrolan in the isolated rat kidney

The direct effects of iotrolan, a non-ionic dimer, on renal function were compared to iopromide, a non-ionic monomer and diatrizoate, an ionic monomer using the isolated perfused rat kidney. Kidneys were perfused ex vivo at 100 mmHg in a recirculating perfusion system with an albumin-based perfusate containing angiotensin II. All contrast media were studied at starting concentration of 20 mg Iodine/ml of renal perfusate. Each contrast agent produced a biphasic effect on the glomerular filtration rate (GFR) characterised by a transient increase followed by a sustained fall. However, the sustained fall in GFR induced by iotrolan (-24.7 +/- 2.1%) was significantly smaller than that produced by diatrizoate (-40.6 +/- 3.5%, P < 0.05) but there was no significant difference in comparison to the fall induced by iopromide (-34.2 +/- 3.7%). Each contrast agent produced a sustained decrease in renal perfusate flow (RPF) with iotrolan exerting a significantly smaller response (-21.7 +/- 2.0%) than either diatrizoate (-29.4 +/- 2.6%, P < 0.05) or iopromide (-32.2 +/- 2.9%, P < 0.05). The results indicate that at an equivalent iodine concentration iotrolan produces a smaller reduction of renal function in comparison to either iopromide or diatrizoate.