title: Progressive development of renal vascular dysfunction in brain death implicates reversible alterations of nitric oxide metabolism.
abstract: BACKGROUND
  Vascular endothelial dysfunction occurs in the kidney graft from marginal brain death (BD) donors and may be responsible for a low success rate after transplantation.
  
  
  METHODS
  BD was induced in 16 dogs for 6 hours. Immediately after the inflation of the intracranial balloon, the treated group (n = 8) received 40 mg/kg bolus followed by 3 mg/kg/min infusion of L-arginine for 30 minutes. Renal vascular function and hemodynamic and biochemical parameters were determined.
  
  
  RESULTS
  BD caused vasoconstriction, increase in renal venous nitrite (4.9 ± 0.8 versus 2.6 ± 0.1, P < .05) and myeloperoxidase levels (1.43 ± 0.04 versus 2.43 ± 0.23, P < .001), and reduced vasodilatation of renal artery to acetylcholine. Larginine diminished the renal vasoconstriction induced by 6 hour BD (RVR = 0.92 ± 0.06 versus 1.38 ± 0.003 in controls, P < .05), maintained renal oxygen extraction in physiological range (17.5 ± 4.6% versus 25.4 ± 2.9% in controls, P < .05) and prevented the rise of myeloperoxidase (1.69 ± 0.19, P < .05 versus controls) and nitrite levels (3.3 ± 0.5, P < .05), followed by preservation of endothelium dependent vasodilatation (P < .05 versus controls).
  
  
  CONCLUSIONS
  The findings suggest that exogenous L-arginine supplementation may preserve endothelial vascular function in the kidney before prelevation from marginal BD donors.
authors.affiliation: Department of Cardiac, Thoracic and Vascular Surgery, Johannes Gutenberg University, Mainz, Germany.
authors.forename: T B
authors.initials: TB
authors.lastname: Andrási
authors.forename: N
authors.initials: N
authors.lastname: Stumpf
authors.forename: A
authors.initials: A
authors.lastname: Blázovics
mesh_terms: D000818:Animals; D001808:Blood Vessels; D001926:Brain Death; D018450:Disease Progression; D004285:Dogs; D006439:Hemodynamics; D007668:Kidney / Q000098:blood supply*; D009569:Nitric Oxide / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide