title: Dexmedetomidine preconditioning attenuates global cerebral ischemic injury following asphyxial cardiac arrest.
abstract: OBJECTIVE
  To investigate the protection effect of dexmedetomidine preconditioning on global cerebral ischemic injury following asphyxial cardiac arrest (CA) in rats.
  
  
  METHODS
  Seventy-two rats were randomly assigned into three groups, sham group (no asphyxia), control group (asphyxia only), and dexmedetomidine preconditioned group (asphyxia + dexmedetomidine). Dexmedetomidine was administered 5 minutes before an 8 min of asphyxia. Rats were resuscitated by a standardized method. Blood O(2) and CO(2) partial pressures were, pH, base excess (BE), and blood glucose concentration measured before asphyxial CA and 1 h after resuscitation. Neurological deficit score (NDS) was measured at 12, 24, 48, and 72 h after CA. Histopathologic changes in the hippocampal region were observed by H&E staining and histopathologic damage score. Ultrastructural morphology was observed by transmission electron microscopy. HIF-1 and VEGF expression were measured by immunostaining of serial sections obtained from brain tissue.
  
  
  RESULTS
  Asphyxial CA -induced global cerebral ischemic decreased PaO(2), pH, BE and increased PaCO(2), blood glucose. Dexmedetomidine preconditioning improved neurologic outcome, which was associated with reduction in histopathologic injury measured by H&E staining, the histopathologic damage score and electron microscopy. Dexmedetomidine preconditioning also elevated HIF-1α and VEGF expression after global cerebral ischemia following asphyxial CA.
  
  
  CONCLUSIONS
  Dexmedetomidine preconditioning protected against cerebral ischemic injury and was associated with upregulation of HIF-1α and VEGF expression.
authors.affiliation: a Department of Anesthesiology, Shengjing Hospital , China Medical University , Shenyang , China.
authors.forename: Xu-Dong
authors.initials: XD
authors.lastname: Ding
authors.affiliation: b Department of Pathophysiology, College of Basic Medical Science , China Medical University , Shenyang , China.
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Zheng
authors.affiliation: a Department of Anesthesiology, Shengjing Hospital , China Medical University , Shenyang , China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Cao
authors.affiliation: a Department of Anesthesiology, Shengjing Hospital , China Medical University , Shenyang , China.
authors.forename: Guang-Yi
authors.initials: GY
authors.lastname: Zhao
authors.affiliation: a Department of Anesthesiology, Shengjing Hospital , China Medical University , Shenyang , China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhao
mesh_terms: D058647:Adrenergic alpha-2 Receptor Agonists / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D001237:Asphyxia / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D002545:Brain Ischemia / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D020927:Dexmedetomidine / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D006323:Heart Arrest / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D019194:Ischemic Preconditioning / Q000379:methods*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; C497444:Hif1a protein, rat; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; D020927:Dexmedetomidine
keywords: HIF-1α; VEGF; asphyxial cardiac arrest; dexmedetomidine; global cerebral ischemia