The effect of felodipine on renal function and blood pressure in cyclosporin-treated renal transplant recipients during the first three months after transplantation.
BACKGROUND
Due to their vasodilatory effect, calcium antagonist may have a renoprotective against cyclosporin (CsA)-induced nephrotoxicity and rise in blood pressure (BP) seen in renal transplantation.


METHODS
In order to evaluate the effect of the calcium antagonist felodipine on renal function and BP during cyclosporin treatment, 79 CsA-treated renal transplant recipients were investigated during the first 3 months after transplantation in a randomized, double-blind, placebo-controlled study with two parallel groups. Felodipine (ER tablets, 10 mg) or placebo was given prior to transplantation and each day during the study period. The patients were assessed twice, i.e. at 4-6 weeks and at 10-12 weeks after transplantation. Renal plasma flow (RPF) and glomerular filtration rate (GFR) were measured by constant infusion technique. Tubular function was estimated from clearance of lithium.


RESULTS
At 6 weeks after transplantation, felodipine caused a significantly higher RPF [felodipine: 219 +/- 70 ml/min; placebo: 182+/-56 ml/min (mean+/-1 SD); P=0.03]. No differences were found in GFR, filtration fraction (FF), tubular sodium handling, or sodium excretion. Felodipine lowered BP significantly. At 12 weeks after transplantation, felodipine caused a significantly higher GFR (felodipine: 49+/-18 ml/min; placebo: 40+/-16 ml/min; P=0.05) and RPF (felodipine: 225+/-77 ml/min; placebo: 175+/-48 ml/min; P<0.01). No difference was found in FF. Felodipine lowered BP significantly. No differences were found with regard to duration of primary anuria, hospitalization time, number of rejection episodes, plasma creatinine day 7 post-transplant, or treatment doses of CsA.


CONCLUSIONS
It is concluded that in renal transplant recipients treated with CsA, felodipine significantly increased both GFR and RPF 3 months after transplantation when compared with placebo, despite a concomitant lowering of BP. A possible antagonizing affect of felodipine against CsA-induced nephrotoxicity in these patients is suggested.
Department of Medicine and Nephrology C, Skejby Hospital, University Hospital in Aarhus, Denmark.
J K
JK
Madsen
S S
SS
Sørensen
H E
HE
Hansen
E B
EB
Pedersen
D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D016572:Cyclosporine / Q000627:therapeutic use*; D004311:Double-Blind Method; D015736:Felodipine / Q000627:therapeutic use*; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D012079:Renal Circulation / Q000187:drug effects; D014665:Vasodilator Agents / Q000627:therapeutic use*
D002121:Calcium Channel Blockers; D007166:Immunosuppressive Agents; D014665:Vasodilator Agents; D016572:Cyclosporine; D015736:Felodipine