IMPROVEMENT IN RENAL-FUNCTION BY FELODIPINE DURING CYCLOSPORINE TREATMENT IN ACUTE AND SHORT-TERM STUDIES

The purpose was to study whether the calcium entry, blocker, felodipin e, could reduce the nephrotoxic and hypertensive effect of cyclosporin e. The effect of felodipine on glomerular filtration rate (GFR), renal plasma flow (RPF), fractional excretion of sodium, lithium clearance and blood pressure was measured in three randomized, placebo-controlle d studies of cyclosporine treated patients. In study one, 10 renal tra nsplant recipients were examined within the first six months after tra nsplantation in a cross-over design. Renal hemodynamics were determine d after the acute ingestion of felodipine or placebo, with an interval of less than one week between the two examinations. In study two, 79 renal transplant recipients were randomized to a treatment with felodi pine or placebo just before transplantation. and renal hemodynamics we re determined after twelve weeks. In study three, 18 patients, who wer e treated with cyclosporine due to dermatological diseases, were exami ned in a cross-over design to determine their renal hemodynamics after four weeks of treatment with felodipine or placebo. Felodipine increa sed renal hemodynamics in study one (GFR 16%, RPF 33%, P < 0.01 for bo th), in study two (GFR 23%, RPF 28%, P < 0.05 for both), and in study three (GFR 13%, RPF 26%, P < 0.01 for both). FE(Na) was significantly increased by felodipine in studies one and three. but not in study two . Lithium clearance was significantly increased and blood pressure sig nificantly reduced by felodipine in all three studies. It can be concl uded that felodipine counteracts both the cyclosporine induced impairm ent in renal hemodynamics and the increase in blood pressure in acute and short-term studies.