title: [The cardioprotection of estrogen on solated global myocardial ischemia/reperfusion injury in ovariectomized rats].
abstract: OBJECTIVE
  To investigated the effect of estrogen on global myocardial ischemia/reperfusion (I/R) injury in ovariectomized (Ovx) rats.
  
  
  METHODS
  Sprague-Dawley rats were randomly repartitioned into three groups including sham-operated(Sham), ovariectomized (Ovx), or ovariectomized and then given 17beta-estradiol (Ovx + E2). Hearts were excised, mounted on the Langendorff. After the initial stabilization period, all of the three group hearts were randomly divided into normal perfusion subgroup (Control) and I/R perfusion subgroups. Control, perfused for 60 min after stabilization. I/R perfusion subgroups divided into 10 min I + 30 min R, 20 min I + 30 min R, 30 min I + 0 min R, 30 min I + 5 min R, 30 min I + 15 min R and 30 min I + 30 min R. And then, every group hearts were isolated into the single cardiomyocyte. The cardiomyocytes basal contraction and isoproterenol(ISO) stimulation contraction were measured. The viability and yield of cardiomyocytes were counted. LDH and CK concentrations in coronary effluent were assayed with assay kit.
  
  
  RESULTS
  The viability and yield of cardiomyocytes were significantly decreased in the conditions of 30 min ischemia followed by different times of reperfusion. The releases of LDH and CK in coronary effluent were significantly increased in the conditions of 30 min ischemia followed by different times of reperfusion. Except the 10 min and 20 min ischemia, the releases of LDH and CK were significantly increased in Ovx during I/R. Ovx + E2 could abate the heart injury through decreasing the releases of LDH and CK. Besides the control and the 10 min I + 30 min R groups, the myocardial basal and ISO stimulation contraction were higher from Ovx than Sham, and the effect was reversed by Ovx + Ez.
  
  
  CONCLUSIONS
  The results indicate estrogen plays a cardioprotective role in global myocardial ischemia/reperfusion injury in ovariectomized (Ovx) rats.
authors.affiliation: Department of Physiology, Xuzhou Medical College, Neumrobiology Center, Xuzhou, Jiangsu 221002, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhao
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yan-ling
authors.initials: YL
authors.lastname: Hao
authors.forename: Yi-wei
authors.initials: YW
authors.lastname: Sun
mesh_terms: D000818:Animals; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D009200:Myocardial Contraction / Q000502:physiology; D017202:Myocardial Ischemia / Q000503:physiopathology*; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000502:physiology*; D010052:Ovariectomy; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004967:Estrogens; D004958:Estradiol