Dötsch J, Hänze J, Knüfer V, Steiss J O, Dittrich K, Seidel A, Rascher W
Department of Pediatrics, Justus-Liebig-Universität, Giessen, Germany.
Nephrol Dial Transplant. 1998 Jul;13(7):1686-9. doi: 10.1093/ndt/13.7.1686.
Adrenomedullin (AM), a smooth-muscle relaxant peptide, is stimulated by cytokines and bacterial endotoxins. We hypothesized that urinary-tract infections may be associated with elevated urinary AM excretion.
AM in urine was quantified in eleven children with urinary-tract infection and 11 age- and sex-matched controls by radioimmunoassay. RT-PCR was used to demonstrate local AM mRNA expression in the urinary tract.
In healthy controls but not in diseased children there was a significant correlation between AM and creatinine in urine (r = 0.91, P < 0.001). AM levels in children with urinary-tract infection were significantly higher than in controls (0.6 +/- 0.41 vs 0.15 +/- 0.14 ng/micromol creatinine; P < 0.001; (means +/- SD)). There was a significant correlation between white cell count and AM in urine (r = 0.78, P < 0.001). AM mRNA was expressed in renal tissue, renal pelvis, ureter, bladder, and urethra.
The smooth-muscle relaxant peptide adrenomedullin that is synthesized in tissue of the human urinary tract is elevated in urine of patients with urinary-tract infections. A possible consequence might be the interference with the ureteral anti-reflux mechanisms.
