Effect of Cardiac Ischemic Preconditioning on Myocardium With its Mechanism in Aged Rats
10.3969/j.issn.1000-3614.2014.08.017
- VernacularTitle:心肌缺血预适应作用对老年大鼠心肌的影响及其机制的研究
- Author:
Jinsong HAN
;
Huishan WANG
;
Hongguang HAN
;
Zongtao YIN
;
Zengwei WANG
- Publication Type:Journal Article
- Keywords:
Aging;
Ischemic preconditioning;
Ischemia-reperfusion;
PGC-1α
- From:
Chinese Circulation Journal
2014;(8):624-628
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To explore the impact of Ischemic preconditioning (IPC) in aged experimental rats after myocardial ischemia-reperfusion (I/R) with its mechanism.
Methods: A total of 32 Wistar rats at the age of (21-23) months were divided into 4 groups, n=8 in each group.①Control group, the rats received cardiac perfusion for 180 min. ②I/R group, the rats received cardiac perfusion for 30 min, followed by ischemia for 30 min, then reperfusion for 120min.③IPC group, the rats received cardiac perfusion for 10 min, followed by ischemia and reperfusion 2 times (5 min in each time), then ischemia 30 min and reperfusion 120 min. ④ Enhanced IPC group, rats received cardiac perfusion for 10 min, followed by ischemia and reperfusion 4 times (5 min in each time), then ischemia 30 min and reperfusion 120 min. The recovery rate of cardiac output (CO), left ventricular developed pressure (LVDP) and the recovery rate of maximum rise and fall of left ventricular pressure (±dp/dtmax) at (30, 60, 90, 120) min after reperfusion were recorded respectively. The creatine kinase (CK-MB), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were examined before ischemia and 120 min after reperfusion. The apical peroxisome proliferator-activated receptorγco-stimulatory factor 1α(PGC-1α) was examined by immuno-histochemistry.
Results: The MDA content, CK-MB, SOD activities LVDP and (±dp/dtmax) recovery were similar between IPC group and I/R group, P>0.05. While compared with I/R group, the Enhanced IPC group showed decreased CK-MB activity and MDA content, increased SOD activity and CO, LVDP and (±dp/dtmax) recovery rate, all P<0.01. The PGC-1αexpression was similar between IPC group and I/R group, P>0.05. While compared with I/R group, the Enhanced IPC group had increased PGC-1αexpression, P<0.01.
Conclusion: The cardiac IPC was weakened in aged rats which might be because of decreased PGC-1αexpression, the enhanced IPC may up-regulate PGC-1αexpression and therefore, protect the cardiac tissue in aged experimental rats.
