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.
Laboratoire d'Explorations Fonctionnelles Rénales et Métaboliques, Hôpital de Rangueil, CHU de Toulouse, France.
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I
Tack
L
L
Rostaing
T
T
Tran-Van
J J
JJ
Lloveras
D
D
Durand
J M
JM
Suc
J L
JL
Ader
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