REDUCED DEPRESSION OF RENAL-FUNCTION BY IOTROLAN IN THE ISOLATED RAT-KIDNEY

The direct effects of iotrolan, a non-ionic dimer, on renal function w ere compared to iopromide, a non-ionic monomer and diatrizoate, an ion ic monomer using the isolated perfused rat kidney. Kidneys were perfus ed ex vivo at 100 mmHg in a recirculating perfusion system with an alb umin-based perfusate containing angiotensin II. All contrast media wer e studied at starting concentration of 20 mgIodine/ml of renal perfusa te. Each contrast agent produced a biphasic effect on the glomerular f iltration rate (GFR) characterised by a transient increase followed by a sustained fall. However, the sustained fall in GFR induced by iotro lan (-24.7 +/- 2.1%) was significantly smaller than that produced by d iatrizoate (-40.6 +/- 3.5%, P <0.05) but there was no significant diff erence 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 io promide (-32.2 +/- 2.9%, P <0.05). The results indicate that at an equ ivalent iodine concentration iotrolan produces a smaller reduction of renal function in comparison to either iopromide or diatrizoate.