Effect of losartan on myocardial ischemia-reperfusion induced activation of NF-?B in rats
- VernacularTitle:氯沙坦对心肌缺血再灌注损伤大鼠心肌NF-?B表达的影响
- Author:
Ling GAO
;
Yanlin WANG
;
Chengyao WANG
- Publication Type:Journal Article
- Keywords:
Losartan;
Myocardial reperfusion injury;
NF-kappa B
- From:
Chinese Journal of Anesthesiology
1995;0(02):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of angiotensin Ⅱ type Ⅰ receptor antagonist losartan on the infarct size and ultrastructure of myocardium and activation of NF-?B induced by myocardial ischemia and reperfusion (I/R) and the possible underlying mechanism. Methods Forty-two healthy male SD rats weighing 215-285 g were randomly divided into 4 groups: in control group ( n = 6) the anterior descending branch of left coronary artery (LCA) was exposed but not occluded; in I/R group (n = 12) the anterior descending branch of LCA was occluded for 30 min followed by 60 min reperfusion; in group LOS1 ( n = 12) and group LOS2 ( n = 12) losartan 5 mg (LOS1) or 10 mg (LOS2) was injected i.v. 15 min before myocardial ischemia. At the end of 60 min reperfusion the animals were killed and the hearts were harvested for determination of (1) myocardial infarct size (by TTC) , (2) ultrastructure of myocardium (electron microscope) and (3) activation of NF-?B.Results The infarct size in group LOS1 (34.6%?2.2%) and LOS2 (21.8%?4.0%) was significantly smaller than that in I/R group (45.4%?2.4%). Myocardial ultrastructure was well preserved in group LOS1 and LOS2 as compared to I/R group. NF-?B activity was significantly increased in I/R group and losartan pretreatment significantly reduced the increase in NF-?B induced by I/R. Conclusion Angiotensin Ⅱ type Ⅰ receptor antagonist losartan has cardioprotective effect on myocardium against I/R in a dose-dependent manner. Modulation of NF-?B activated by I/R may be involved in the mechanism.
