Renal functional reserve in calcium channel blocker-treated hypertensive recipients of kidney transplant.
Renal functional reserve during infusion of an amino acid solution was examined in 12 cyclosporin-treated kidney recipients at 1 (T1) and 8 months (T2) after transplantation. Patients were retrospectively divided into six normotensive (NT) and six hypertensive recipients (HT) maintained on monotherapy with a calcium channel blocker. Baseline glomerular filtration rates (GFR) were similar in NT and HT at T1 and T2. Renal functional reserve was identical in NT and HT at T1 (15 +/- 7 vs 18 +/- 13 ml/min/1.73 m2) but significantly greater in HT at T2 (11 +/- 5 vs 23 +/- 10 ml/min/1.73 m2; P < 0.05). At T2, baseline proximal tubule outflow (lithium clearance) was greater in HT (26 +/- 8 vs 16 +/- 3 ml/min/1.73 m2; P < 0.05), whereas fractional proximal reabsorption was less (54 +/- 11% vs 67 +/- 5%; P < 0.05). These results indicate that: (i) hypertensive recipients on calcium channel blocker therapy do not exhibit permanent glomerular hyperfiltration until 8 months after transplantation, and have a reduced proximal reabsorption; (ii) measurement of amino acid-stimulated GFR and renal functional reserve is a more sensitive method than that of baseline GFR for evaluating renal function and the effects of therapy in kidney recipients.
Tack
I
I
Laboratoire d'Explorations Fonctionnelles Rénales et Métaboliques, Hôpital de Rangueil, CHU de Toulouse, France.
Rostaing
L
L
Tran-Van
T
T
Lloveras
J J
JJ
Durand
D
D
Suc
J M
JM
Ader
J L
JL
D000328:Adult; D000596:Amino Acids / Q000008:administration & dosage; D002121:Calcium Channel Blockers / Q000009:adverse effects / Q000627:therapeutic use*; D016572:Cyclosporine / Q000009:adverse effects; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D006977:Hypertension, Renal / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D017275:Isradipine / Q000627:therapeutic use; D016030:Kidney Transplantation / Q000009:adverse effects / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000627:therapeutic use; D009568:Nitrendipine / Q000627:therapeutic use; D017595:Renal Plasma Flow / Q000187:drug effects; D012189:Retrospective Studies
D000596:Amino Acids; D002121:Calcium Channel Blockers; D016572:Cyclosporine; D009568:Nitrendipine; D009543:Nifedipine; D017275:Isradipine