EFFECT OF RENAL-TRANSPLANTATION ON PLASMA-PROTEIN BINDING

The in vitro plasma protein binding was determined in nine maintenance hemodialysis patients who later underwent renal transplantation. The organic acid fluorescein (10 ug/ml) or the organic base quinidine (5 ug/ml) was added to the pre and post transplant serum of these patients. Drug concentrations were measured spectrophotofluorometrically after equilibrium dialysis. The results were compared with the plasma protein binding of eight normal volunteers. The patients on maintenance hemodialysis had lower plasma protein binding of fluorescein than normals (78 ± 5% vs 89 ± 4, p < 0.001). Plasma protein binding improved significantly after renal transplantation (85 ± 3, p < 0.01) but was still lower than in normals (p < 0.05). Plasma protein binding of quinidine was not significantly different than in normal volunteers (77 ± 8% either prior to (72 ± 10% or after (73 ± 12% kidney transplantation. Plasma protein binding of quinidine remains unaffected by renal transplantation. However, the abnormal plasma protein binding of organic acids in chronic renal failure may be significantly improved by renal transplantation. © 1979 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.