title: Prevention of post-cardiopulmonary bypass acute kidney injury by endothelin A receptor blockade.
abstract: OBJECTIVE
  The aim of this study was to determine whether administration of a specific endothelin A receptor antagonist, sitaxsentan sodium, would prevent the development of post-cardiopulmonary bypass acute kidney injury in swine.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Cardiovascular Research Institute.
  
  
  METHODS
  Adult pigs (n = 8 per group) were randomized to undergo a sham procedure, cardiopulmonary bypass, or cardiopulmonary bypass plus administration of endothelin A receptor antagonist (RA), with recovery and reassessment at 24 hrs.
  
  
  RESULTS
  Cardiopulmonary bypass resulted in a significant reduction in creatinine clearance relative to sham pigs (mean difference for cardiopulmonary bypass vs. sham, -50.3 mL/min [95% confidence interval -89.2 to -11.4 mL/min], p = .008). This was reversed by the administration of endothelin A RA during cardiopulmonary bypass (mean difference for cardiopulmonary bypass + endothelin A RA vs. cardiopulmonary bypass, +43.3 mL/min [95% confidence interval +3.3 to +83.4 mL/min], p = .030). Cardiopulmonary bypass also resulted in a significant rise in the specific urinary biomarker of acute kidney injury interleukin-18 compared to sham procedures (mean difference +209 pg/mL [95% confidence interval +119 to +299 pg/mL], p < .001) that was reversed by endothelin A receptor antagonist administration. Post-cardiopulmonary bypass kidney injury was associated with vascular endothelial injury and dysfunction, reduced nitric oxide bioavailability, inflammation, and a significant increase in the expression of the paracrine vasoconstrictors adenosine and endothelin-1. In post-cardiopulmonary bypass kidneys at 24 hrs there was persistent hypoxia at the level of the outer medulla, cortical adenosine triphosphate depletion, and evidence of proximal tubule epithelial cell stress manifest as phenotypic change. There was no evidence of acute tubular necrosis. Administration of endothelin A RA to cardiopulmonary bypass pigs reversed endothelial dysfunction, regional hypoxia, inflammation, and tubular changes.
  
  
  CONCLUSIONS
  In this model, post-cardiopulmonary bypass acute kidney injury is associated with endothelial dysfunction, regional tissue hypoxia, and proximal tubular epithelial cell stress but not acute tubular necrosis. Antagonism of the endothelin-1 A receptor reversed these changes and may represent a therapeutic target for the prevention of post-cardiac surgery acute kidney injury.
authors.affiliation: Bristol Heart Institute, University of Bristol, Bristol Royal Infirmary, Bristol, United Kingdom.
authors.forename: Nishith N
authors.initials: NN
authors.lastname: Patel
authors.forename: Tibor
authors.initials: T
authors.lastname: Toth
authors.forename: Ceri
authors.initials: C
authors.lastname: Jones
authors.forename: Hua
authors.initials: H
authors.lastname: Lin
authors.forename: Paramita
authors.initials: P
authors.lastname: Ray
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: George
authors.forename: Gavin
authors.initials: G
authors.lastname: Welsh
authors.forename: Simon C
authors.initials: SC
authors.lastname: Satchell
authors.forename: Philippa
authors.initials: P
authors.lastname: Sleeman
authors.forename: Gianni D
authors.initials: GD
authors.lastname: Angelini
authors.forename: Gavin J
authors.initials: GJ
authors.lastname: Murphy
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D000818:Animals; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D065130:Endothelin A Receptor Antagonists; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology; D005260:Female; D020382:Interleukin-18 / Q000652:urine; D007555:Isoxazoles / Q000494:pharmacology / Q000627:therapeutic use*; D011507:Proteinuria / Q000378:metabolism; D012079:Renal Circulation / Q000187:drug effects / Q000502:physiology; D013552:Swine; D013876:Thiophenes / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D065130:Endothelin A Receptor Antagonists; D020382:Interleukin-18; D007555:Isoxazoles; D013876:Thiophenes; D003404:Creatinine; C106276:sitaxsentan