title: [Role of mitochondrial calcium uniporter in myocardial hypoxia/reoxygenation induced injury].
abstract: OBJECTIVE
  To investigate the role and mechanism of mitochondrial calcium uniporter (MCU) in myocardial hypoxia/reoxygenation injury.
  
  
  METHODS
  Isolated rat hearts were perfused with Langendorff apparatus. The hypoxia/reoxygenation injury was achieved by ligation of left anterior coronary artery for 30 min followed by release of ligation for 120 min. The left ventricular developed pressure (LVDP), the maximum rise/fall rate of left ventricular pressure (+/- dP/dt(max)), and the left ventricular end-diastolic pressure (LVEDP) were recorded. Activities of lactate dehydrogenase (LDH) in coronary effluent and reactive oxygen species (ROS) of myocardial mitochondria were spectrophotometrically assayed. Infarct size was determined by TTC staining method.
  
  
  RESULTS
  Compared with the hypoxia/reoxygenation (H/R) group, ruthenium red (RR, 5 micromol/L), given at the on set of reoxygenation, significantly improved the contractile function of left ventricle, decreased the myocardial infarct size, alleviated the production of ROS in myocardial mitochondria and LDH release in coronary effluent. Spermine (20 micromol/L), given at the onset of reoxygenation, enhanced the production of ROS in the mitochondria and LDH release in coronary effluent at 5, 20 and 30 min of reoxygenation, however, there were no significant differences of ventricular contractile parameters and infarct size between groups subjected to hypoxia/reoxygenation with or without spermine treatment. Co-treatment of ROS scavenger N-2-mercaptopropionyl glycine (1 mmol/L) with spermine abolished the effect of spermine.
  
  
  CONCLUSIONS
  Inhibition of mitochondrial calcium uniporter may refrain heart from hypoxia/reoxygenation injury via decreasing the production of ROS in heart mitochondria.
authors.affiliation: Lishui College, Lishui 323000, China.
authors.forename: Ting-Mei
authors.initials: TM
authors.lastname: Ye
authors.forename: Shi-Zhong
authors.initials: SZ
authors.lastname: Zhang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xia
mesh_terms: D000818:Animals; D015220:Calcium Channels / Q000378:metabolism*; D015687:Cell Hypoxia; D066298:In Vitro Techniques; D008297:Male; D008929:Mitochondria, Heart / Q000378:metabolism*; D017202:Myocardial Ischemia / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D017382:Reactive Oxygen Species; C034703:mitochondrial calcium uniporter