title: [Effects of angiotensin-(1-7) on oxidative stress and functional changes of isolated rat hearts induced by ischemia-reperfusion].
abstract: OBJECTIVE
  To investigate the effects of angiotensin (Ang)-(1-7) on oxidative stress and functional changes in isolated rat hearts with myocardial ischemia-reperfusion (IR) injury.
  
  
  METHODS
  IR injury was induced in isolated rat hearts with the Langendorff' apparatus. The left ventricular systolic pressure (LVSP) of the rat heart was measured using a pressure transducer. Malondialdehyde (MDA) level and superoxide dismutase (SOD) activity in the myocardium were detected using commercial kits.
  
  
  RESULTS
  Myocardial ischemia (15 min) and reperfusion (30 min) significantly increased myocardial levels of MDA, and reduced the SOD activity and LVSP (P<0.05). Pretreatment with Ang-(1-7) at 1.0 nmol/L 30 min before ischemia obviously inhibited IR-induced MDA increment and lowering of SOD activity and LVSP. Pretreatment of the rats with intraperitoneal injection of 5 mg/kg indomethacin 1 h before isolation of the heart markedly antagonized the effect of Ang-(1-7) on MDA production, SOD activity and LVSP.
  
  
  CONCLUSIONS
  Angiotensin-(1-7) can inhibit IR injury-induced oxidative stress and decrease in cardiac contractile function in isolated rat hearts. The mechanism underlying the effect of Ang-(1-7) may be associated with increased secretion of prostaglandin.
authors.affiliation: Department of Cardiology, Zhongshan Medical College, Sun Yat-sen University, Guangzhou, China. liaoxinx@mail.sysu.edu.cn
authors.forename: Xin-xue
authors.initials: XX
authors.lastname: Liao
authors.forename: Rui-xian
authors.initials: RX
authors.lastname: Guo
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.forename: Li-chun
authors.initials: LC
authors.lastname: Wang
authors.forename: Zheng-hua
authors.initials: ZH
authors.lastname: Chen
authors.forename: Chun-tao
authors.initials: CT
authors.lastname: Yang
authors.forename: Jian-qiang
authors.initials: JQ
authors.lastname: Feng