title: [Changes of leptin levels in serum and myocardium after myocardial ischemia/reperfusion injury].
abstract: OBJECTIVE
  To explore the effect of rat myocardial ischemia/reperfusion injury on leptin levels in serum and myocardium, and discuss the role of leptin in myocardial ischemia/reperfusion injury.
  
  
  METHODS
  A myocardial ischemia/reperfusion injury model of rats was established, serum lactate dehydrogenase (LDH) and leptin levels were detected, and histopathological changes and leptin expressions in myocardium were investigated by hematoxylin-eosin staining and immunohistochemistry, respectively.
  
  
  RESULTS
  Serum LDH of ischemia and reperfusion groups increased significantly (P < 0.05), suggesting the model was successfully established and a certain degree of local myocardial injury was induced. Serum leptin of ischemia group (6.34 +/- 2.49) ng/ml was significantly lower than control group (7.50 +/- 2.93 ng/ml, P <0.05). Leptin levels recovered gradually after reperfusion, reached (8.32 +/- 1.74)ng/ml at 2 h after reperfusion, which recovered to the level before injury (8.38 +/- 2.56) ng/ml, and showed a trend to increase as reperfusion time was elongated. Immunohistochemistry results showed that as compared with sham-operation group, myocardial leptin protein expressions of the other four groups were all significantly lower (P < 0.01), and decreased in order by 45 min ischemia/1 h reperfusion, 45 min ischemia/3 h reperfusion, 45 min ischemia and 45 min ischemia/2 h reperfusion.
  
  
  CONCLUSIONS
  Leptin level in the blood decreases significantly at the early 45 min after myocardial ischemia/reperfusion injury, and its expression in myocardium also decreases significantly. There may be a certain relationship between the pathological injury of myocardium and the changes of leptin.
authors.affiliation: Research Laboratory of Biochemistry, Basic Medical Institute, General Hospital of PLA, Beijing 100853, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Xue
authors.forename: Guang-tao
authors.initials: GT
authors.lastname: Yan
authors.forename: Ji
authors.initials: J
authors.lastname: Lin
authors.forename: Xiu-hua
authors.initials: XH
authors.lastname: Hao
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
mesh_terms: D000818:Animals; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D020738:Leptin / Q000097:blood / Q000378:metabolism*; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000503:physiopathology*; D009206:Myocardium / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020738:Leptin; D007770:L-Lactate Dehydrogenase