M. Franz et al., N-terminal fragments of the proatrial natriuretic peptide in plasma and urine of kidney graft recipients, TRANSPLANT, 72(1), 2001, pp. 89-94
Background. Successful kidney transplantation normalizes elevated proatrial
natriuretic peptide (proANP) plasma concentrations of renal failure patien
ts in the early posttransplant period. We evaluated plasma and urinary proA
NP fragments in the late posttransplant period.
Methods. Immunoreactive proANP(1-30) and proANP(31-67) were determined in 3
89 renal transplant (Rtx) recipients in the long-term, follow-up period and
in 16 healthy controls.
Results. Rtx recipients had significantly higher concentrations of proANP(1
-30) and proANP(31-67) in both plasma and urine than healthy controls. Alth
ough their graft function was normal, all of these long-term Rtx recipients
were taking glucocorticoids, which increase proANP(1-30) and proANP(31-67)
in the circulation to the extent found in this investigation. Two-thirds o
f these recipients were also talking cyclosporine, which also increases atr
ial peptides. Urinary proANP(31-67) was significantly higher than urinary p
roANP(1-30); 5.5-fold in Rtx patients and 2-fold in controls. Deterioration
of renal graft function was associated with a rise of plasma proANP(1-30)
from 0.98 +/-0.66 to 6.28 +/-3.55 nmol/l (P<0.0001) and plasma proANP(31-67
) from 1.81<plus/minus>1.04 to 7.89 +/-3.76 nmol/l (P<0.0001), Urinary excr
etion of proANP(1-30) increased from 0.27<plus/minus>0.34 to 5.96 +/-5.07 n
mol/24 hr (P<0.0001) and proANP(31-67) from 1.45<plus/minus>0.85 to 12.23 /-5.12 nmol/24 hr (P<0.0001). Also proteinuria enhanced plasma and urinary
proANP fragments.
Conclusions. ProANP(1-30) and proANP(31-67) of Rtx recipients are affected
by immunosuppression, hypertension, renal failure, and proteinuria. One wou
ld have expected proANP(1-30) and proANP(31-67) not to normalize because of
the glucocorticoids that they were receiving.