title: Myocardial ischemic post-conditioning attenuates ischemia reperfusion injury via PTEN/Akt signal pathway.
abstract: OBJECTIVE
  To investigate whether myocardial ischemic post-conditioning attenuates ischemia reperfusion injury via PTEN/Akt signal pathway.
  
  
  METHODS
  Forty-five male Sprague-Dawley rats were randomly divided into three groups: Sham, Ischemia reperfusion (I/R) and Ischemic post-conditioning (IPost) group. After the experiment finished, myocardial infarction area was examined. Serum creatine phosphokinase and lactate dehydrogenase activity were detected at baseline and the end of reperfusion. The protein levels of PTEN, Akt, p-Akt, Bax and Bcl-2 were measured by Western blot method.
  
  
  RESULTS
  Myocardial infarct size was significantly reduced in IPost as compared to I/R. Results were confirmed by serum creatine phosphokinase and lactate dehydrogenase activity. In addition, PTEN and Bax protein expression were inhibited and the p-Akt and bcl-2 protein expression were enhanced in IPost compared with I/R (P < 0.05). At the same time, the ratio of Bax and Bcl-2 was decreased in IPost (P < 0.05). However, ischemic post conditioning did not affect the total Akt level (P > 0.05).
  
  
  CONCLUSIONS
  We confirmed that ischemic post-conditioning protects the heart against reperfusion injury. It is important that we demonstrated that the cardioprotective effect of ischemic post-conditioning was involved in the inhibition of PTEN, activation of the PI3K/Akt pathway and reduction of the cardiomyocyte apoptosis.
authors.affiliation: Department of Cardiology, Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021, Shandong, China.
authors.forename: Chun-Mei
authors.initials: CM
authors.lastname: Li
authors.affiliation: Department of Cardiology, Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021, Shandong, China.
authors.forename: Shu-Wen
authors.initials: SW
authors.lastname: Shen
authors.affiliation: Department of Cardiology, Shandong Traffic Hospital Jinan 250031, Shandong, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021, Shandong, China.
authors.forename: Xing-Hua
authors.initials: XH
authors.lastname: Zhang
keywords: Akt; PTEN; apoptosis; ischemia reperfusion injury; post-conditioning