Nitric Oxide in Patients after Cadaveric Renal Transplantation

Overview

Background.
The role of nitric oxide (NO) after cadaveric renal graft transplantation has not been yet fully clarified.The aim of our study was to examine NO production into the urine of patients following cadaveric renal grafttransplantation with a normal course and complications (acute rejection and cyclosporin toxicity).Methods and Results. Production of stabile NO metabolites (NO 2-and NO 3-) into urine (U-NOx) was examinedin recipients of cadaveric renal transplantation. Only patients with standard triple immunosuppressive therapy(cyclosporin, azathioprine, prednisone) were include into the study. Patients receiving other immunosuppressiveagents or drugs affecting NO formation (nitrates, ACE inhibitors) were excluded from the study, as were those withinfectious or other serious post-transplant complications. Overall, we examined 33 patients (21 men and 12 women),with acute rejection and cyclosporin-induced toxicity in ten each, and a normal course with no complications in 13.The mean age of the patients was 50.96 _ 11.13 years. U-NOx was examined by biochemistry using Griesse reactionevery day after transplantation both in a morning urine sample and in a sample from 24-hour collection over thepreceding day and calculated to 1 mmol/l of urinary creatinine (U-Cr). The levels of U-NOx/U-Cr in patients withacute rejection over the past 2 days before its development were lower compared with those in patients with a normalcourse (p_0.05). No difference was found between the groups of patients with cyclosporin-induced toxicity anda normal course. The levels of U-NOx were inversely correlated (p_0.01) to the levels of serum creatinine (S-Cr),but did not correlate with the blood levels of cyclosporin A.Conclusions.The study demonstrated a decrease in urinary U-NOx production within the past 2 days before renaltransplant rejection. The levels of U-NOx in patients with cyclosporin-induced toxicity remain unaltered. U-NOx/U-Cr could possibly become a non-invasive marker of rejection.

Key words:
NO, cyclosporin, renal transplantation, acute rejection, cyclosporin-induced toxicity.