title: Effect of exogenous phosphocreatine on cardiomycytic apoptosis and expression of Bcl-2 and Bax after cardiopulmonary resuscitation in rats.
abstract: BACKGROUND
  Ischemia-reperfusion injury in the myocardium after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) is an important pathologic basis of post-cardiac arrest of syndrome (PCAS), and apoptosis is one of the major mechanisms in myocardial ischemia-reperfusion injury. To lessen myocardial ischemia-reperfusion injury after cardiac arrest and CPR, it is important to reduce energy consumption and to increase energy supply in the myocardium. This study aimed to observe changes of cell apoptosis and expression of Bcl-2 and Bax protein on the myocardium after CPR in rats, and the protective effects of different doses of exogenous phosphocreatine (creatine phosphate, CP) on them.
  
  
  METHODS
  A total of 32 male adult Sprague-Dawley rats were randomly divided into 4 groups: control group (group A), CPR group (group B), low-dose CP group (group C, CP 0.5 g/kg at beginning of CPR and 1.0 g/kg at 2 hours after CPR) and high-dose CP group (group D, CP 1.0 g/kg at beginning of CPR and 2.0 g/kg at 2 hours after CPR). Cardiac arrest was induced by asphyxiation and CPR started at 7 minutes after asphyxiation in groups B, C and D. Myocardium samples were taken at 24 hours after CPR. Cardiomycytic apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. The expression of Bcl-2 and Bax protein was measured by immunohistochemistry.
  
  
  RESULTS
  Cardiomyocytic apoptosis index (AI) and expression of Bcl-2 and Bax protein increased more significantly in groups B, C and D than in group A (P<0.01), but Bcl-2/Bax ratio significantly decreased (P<0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax protein decreased more significantly in groups C and D than in group B (P<0.01), but Bcl-2/Bax ratio increased more significantly (P<0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax protein decreased more significantly in group D than in group C (P<0.05), but Bcl-2/Bax ratio increased more significantly (P<0.05).
  
  
  CONCLUSIONS
  Exogenous phosphocreatine, especially at a large dose, could inhibit cardiomyocytic apoptosis and alleviate myocardial injury after CPR in rats.
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yan
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Shou-Quan
authors.initials: SQ
authors.lastname: Chen
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Zhang-Ping
authors.initials: ZP
authors.lastname: Li
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Ji-Ke
authors.initials: JK
authors.lastname: Xue
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Wan-Tie
authors.initials: WT
authors.lastname: Wang
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Wei-Jia
authors.initials: WJ
authors.lastname: Huang
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Jun-Yan
authors.initials: JY
authors.lastname: Cheng
authors.affiliation: Department of Emergency Medicine, First and Second Affiliated Hospitals of Wenzhou Medical College, Wenzhou 325000, China.
authors.forename: Hui-Ping
authors.initials: HP
authors.lastname: Li
keywords: Apoptosis; Bax; Bcl-2; Cardiopulmonary resuscitation; Phosphocreatine; TUNEL