title: Brain death increases COX-1 and COX-2 expression in the renal medulla in a pig model.
abstract: BACKGROUND
  Brain death is linked to a systemic inflammatory response that includes prostaglandins and cytokines among its mediators. The levels of cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2) affect graft survival, but it remains unknown whether these enzymes are modified during brain death. The aims of this study were to investigate the organ expression of COX and to analyse the cytokine response in the plasma, cerebrospinal fluid (CSF), and organs in a porcine model of intracerebral haemorrhage and brain death.
  
  
  METHODS
  Twenty pigs were randomly assigned to either a brain death group or a control group. Brain death was induced by an intracerebral injection of blood, and the animals were observed over the next 8 h. Tissue samples were tested for COX-1, COX-2 messenger RNA (mRNA) expression (heart, lung, and kidney), haeme oxygenase-1 (HO-1) (kidney), interleukin-1β (IL-1β), IL-6, IL-8, IL-10, and tumour necrosis factor-α. These cytokines were also measured at eight time points in the plasma and CSF.
  
  
  RESULTS
  At the organ level, the levels of COX-1 and COX-2 mRNA expression were increased only in the renal medulla (P = 0.03 and P = 0.02, respectively). The cytokine levels in the tissue, plasma, and CSF revealed no differences between the groups. HO-1 expression decreased (P = 0.0088).
  
  
  CONCLUSIONS
  Brain death increases the expression of COX-1 and COX-2 mRNA in the renal medulla. The release of cytokines into the plasma and CSF did not vary between the groups.
authors: Department of Anaesthesiology and Intensive Care Medicine, Aarhus University Hospital, Aarhus C, Denmark; Institute of Clinical Medicine, Aarhus University Hospital, Aarhus N, Denmark.
authors: C L
authors: CL
authors: Hvas
authors: R
authors: R
authors: Nørregaard
authors: T K
authors: TK
authors: Nielsen
authors: A
authors: A
authors: Barklin
authors: E
authors: E
authors: Tønnesen
mesh_terms: D000818:Animals; D001926:Brain Death; D051545:Cyclooxygenase 1 / Q000096:biosynthesis*; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D016207:Cytokines / Q000378:metabolism; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D007672:Kidney Cortex / Q000187:drug effects / Q000378:metabolism; D007679:Kidney Medulla / Q000201:enzymology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification; D060888:Real-Time Polymerase Chain Reaction; D013238:Stereotaxic Techniques; D013552:Swine; D014018:Tissue Distribution
chemical_list: D016207:Cytokines; D017931:DNA Primers; D012333:RNA, Messenger; D004247:DNA; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2