The influence of kidney transplantation on carnitine metabolism.
In this study, we examined all three plasma carnitine fractions, free carnitine (FC), short-chain acyl- (SCC), and long-chain acylcarnitine (LCC), as well as the urinary excretion of FC and SCC in 62 patients with functioning renal allografts 1-70 months following the kidney transplantation (KT). Patients were classified into three groups according to their transplant function, as characterized by the serum creatinine concentration (CR). A comparison with normal subjects (n = 20) and with patients on chronic hemodialysis (HD, n = 46) revealed a complete normalization of all carnitine plasma fractions for group I patients (Cr less than 120 mumol/l). In contrast, significant elevations of plasma free and esterified carnitine were found in group II (Cr greater than 120, less than 200 mumol/l; with FC + 27%, SCC + 82%, and LCC + 49% and group III patients (Cr greater than 200 mumol/l; with FC + 39%, SCC + 122%, and LCC + 106%), as compared to healthy subjects (p less than 0.001). The elevations in concentrations of SCC were more pronounced than those of FC; consequently, we found a higher ratio of acylcarnitine (AC) to FC in group III than in group I patients (+ 41%, p less than 0.001). Yet even in the former group, this ratio was found to be markedly reduced when compared to HD patients (-41%, p less than 0.001). We found no significant differences in the urinary excretion of FC and SCC between the 3 groups of KT patients. It is thus to conclude that in patients with a well-functioning transplant, the pattern of carnitine fractions in plasma is fully normalized. The decrease in the ratio of AC to FC following a successful KT might suggest a better availability of FC and thereby be associated with an enhanced fatty acid oxidation.
Kohse
K P
KP
Department of Internal Medicine I, University of Ulm, FRG.
Dech
E
E
Rössle
C
C
Franz
H E
HE
Fürst
P
P
D000108:Acetylcarnitine / Q000097:blood / Q000378:metabolism / Q000652:urine; D001682:Biological Availability; D002331:Carnitine / Q000097:blood / Q000378:metabolism* / Q000652:urine; D003404:Creatinine / Q000097:blood; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007668:Kidney / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000601:surgery; D016030:Kidney Transplantation; D008297:Male
D000108:Acetylcarnitine; D003404:Creatinine; D002331:Carnitine