title: [Relationship between α-actinin and cardiac function in rats with myocardial ischemia-reperfusion].
abstract: OBJECTIVE
  To explore the relationship between α-actinin content and cardiac function in rats during myocardial ischemia-reperfusion.
  
  
  METHODS
  Thirty-two rats were randomized equally into sham-operated group, 30 min ischemia group, 1 h ischemia group, and 1 h ischemia with 2 h reperfusion group. Acute myocardial ischemia was induced in the 3 ischemia groups by ligation of the left anterior descending coronary artery, and the cardiac functions were evaluated. The myocardial contents of α-actinin was measured by immunohistochemistry, and phospholipase C (PLC) and phosphatidylinositol-3-kinase (PI3K) contents were determined by ELISA after the operations.
  
  
  RESULTS
  The left ventricular systolic pressure (LVSP), +dp/dt max, and -dp/dt max tended to decrease during myocardial ischemia, and increased after reperfusion, and the left ventricular end-diastolic pressure (LVEDP) showed reverse changes. The levels of α-actinin decreased with prolonged ischemia, showing a significant difference in 1 h ischemia group from those in the other 3 groups. PI3K and PLC contents were significantly increased with prolonged myocardial ischemia. Stimulation by LY-294002 and U-73122 caused enhanced contraction of single cardiomyocytes, and also increased the fluorescence intensity of α-actinin in the cardiomyocytes compared with that in 1 h ischemia group.
  
  
  CONCLUSIONS
  The cardiac dysfunction during acute ischemia-reperfusion in rats may be related with the changes of myocardial α-actinin content, which are probably a result of increased PI3K and PLC contents in the ischemic myocardium.
authors.affiliation: Teaching Center of Experimental Medicine, Southern Medical University, Guangzhou 510515, China. cttpikachu@yahoo.com.cn
authors.forename: Tang-ting
authors.initials: TT
authors.lastname: Chen
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhou
authors.forename: Li-qun
authors.initials: LQ
authors.lastname: Wang
authors.forename: Chun-hua
authors.initials: CH
authors.lastname: Jin
mesh_terms: D000185:Actinin / Q000378:metabolism*; D000818:Animals; D017202:Myocardial Ischemia / Q000378:metabolism* / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D000185:Actinin; D058539:Phosphatidylinositol 3-Kinase; D010738:Type C Phospholipases