Effects of the prostacyclin analogue iloprost on cyclosporin-induced renal hypoperfusion in stable renal transplant recipients.

Background. The synthetic prostacyclin analogues have been proposed to protect against cyclosporin A (CsA) nephrotoxicity. The present study investigated the effect of infusion of the prostacyclin analogue iloprost on the acute CsA-induced renal hypoperfusion and hypofiltration in stable renal-transplant recipients. Methods. The study included 10 stable renal-transplant recipients with good graft function (s-creatinine 90–170 umol/1). Renal function and the acute renal haemodynamic and tubular response to an oral CsA-dose (Sandimmun Neoral, 3 mg.kg−1) were investigated with an infusion of iloprost (1 ng.kg−1.min−1) or placebo on 2 separate days. After an overnight fast, seven 30-min renal clearance periods were performed, two before infusion, three during infusion, and two recovery periods. An additional control clearance study without CsA intake or iloprost/placebo infusion was done in eight of the patients. Results. CsA ingestion decreased ERPF and GFR significantly with a maximum decline at the end of the clearance study. Iloprost infusion abolished the CsAinduced decrease in ERPF, but had no effect on the CsA-induced decrease in GFR, leading to a significant decline in FF. Renal clearance of lithium (CLi), used as an index of proximal tubular outflow, decreased in parallel with GFR after CsA intake, with no additional effects of iloprost. Iloprost infusion decreased blood pressure and increased heart rate. Conclusion. Infusion of iloprost causes systemic and renal vasodilatation, but has no effect on the CsA-induced decrease in GFR and CLi in stable renal transplant recipients. [ABSTRACT FROM PUBLISHER]