title: Infusion of radiocontrast agents induces exaggerated release of urinary endothelin in patients with impaired renal function.
abstract: BACKGROUND
  The aim of the study was to examine the role of endothelin in radiocontrast-induced nephropathy (RCN) in patients with chronic renal failure.
  
  
  METHODS
  We measured plasma endothelin-1 (ET) and the urinary excretion of endothelin-like immunoreactivity before and after infusion of radio contrast medium (CM) in patients with normal renal function (group N; n = 6; mean serum creatinine concentration, 0.8 +/- 0.1 (SEM) mg/dl), and in another group, with renal dysfunction (group R; n = 6; 2.7 +/- 0.5 mg/dl). Half-normal saline (0.45% NaCl solution) was continuously infused in all patients for 25 h, at a rate of 100 ml/h; starting from 5 h before the infusion of CM.
  
  
  RESULTS
  Plasma ET in group R (5.2 +/- 1.4 pg/ml) was significantly higher than in group N (0.9 +/- 0.3; P << 0.01). Urinary endothelin excretion corrected by creatinine concentration (uET/Cr) in group R (7.9 +/- 2.4 mg/g Cr) was significantly higher than in group N (1.5 +/- 0.4 mg/g Cr; P << 0.05). Urinary excretion levels of N-acetyl-Beta- d-glucosaminidase (NAG) and Beta2-microglobulin (Beta2M) were also significantly higher in group R (0.8 +/- 0.2 mU/g Cr and 670 +/- 400 mg/g Cr, respectively) than in group N (0.3 +/- 0.1 and 7.5 +/- 2.2, respectively). After CM infusion, uET/Cr in group R significantly increased, to 10.7 +/- 2.6 mg/g Cr on the next day and returned to baseline level on the third day. NAG and Beta2M showed a similar pattern, but a significant change in NAG was observed on the second day in group R. In group N, uET/Cr, NAG, and Beta2M did not change after CM infusion. Plasma ET remained unchanged throughout the observation period of 4 days in both groups. No patient developed pulmonary edema or a significant rise in serum creatinine (more than 0.5 mg/dl), caused by infusion of the amount of half-normal saline used.
  
  
  CONCLUSIONS
  In the present study, uET/Cr increased after the administration of CM only in the patients with renal impairment. This difference in endothelin reaction may be a causal one, in that patients with renal insufficiency readily develop RCN. The infusion of half-normal saline starting before CM infusion causes no side effects and is safe for the prevention of CM-induced acute renal failure. The aim of the study was to examine the role of endothelin in radiocontrast-induced nephropathy (RCN) in patients with chronic renal failure.
authors.affiliation: Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Fujisaki
authors.forename: Michiaki
authors.initials: M
authors.lastname: Kubo
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Masuda
authors.forename: Masanori
authors.initials: M
authors.lastname: Tokumoto
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirakawa
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ikeda
authors.forename: Rei
authors.initials: R
authors.lastname: Matsui
authors.forename: Dai
authors.initials: D
authors.lastname: Matsuo
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Fukuda
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Kanai
authors.forename: Hideki
authors.initials: H
authors.lastname: Hirakata
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
mesh_terms: D000118:Acetylglucosaminidase / Q000097:blood; D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D016232:Endothelins / Q000097:blood / Q000652:urine*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000652:urine*; D007677:Kidney Function Tests; D008259:Macroglobulins / Q000032:analysis / Q000378:metabolism; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media; D016232:Endothelins; D008259:Macroglobulins; D003404:Creatinine; D000118:Acetylglucosaminidase