Effect of dexmedetomidine postconditioning combined with limb ischemic postconditioning on myocardial ischemia-reperfusion injury in rats
10.3760/cma.j.issn.0254-1416.2016.05.013
- VernacularTitle:右美托咪定后处理联合肢体缺血后处理对大鼠心肌缺血再灌注损伤的影响
- Author:
Huan WANG
;
Zhixiang GUO
- Publication Type:Journal Article
- Keywords:
Dexmedetonfidine;
Extremities;
Ischemic postconditioning;
Myocardial reperfusion injury
- From:
Chinese Journal of Anesthesiology
2016;36(5):559-562
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effect of dexmedetomidine postconditioning combined with limb ischemic postconditioning on myocardial ischemia-reperfusion (I/R) injury in rats.Methods Fifty male Sprague-Dawley rats,aged 2-3 months,weighing 275-335 g,were randomly divided into 5 groups (n =10 each) using a random number table:sham operation group (group S);I/R group;dexmedetomidine postconditioning group (group DP);limb ischemic postconditioning group (group LP);dexmedetomidine postconditioning combined with limb ischemic postconditioning group (group DLP).Myocardial I/R was induced by occlusion of the left anterior descending branch of coronary artery for 30 min followed by 180 min reperfusion.At 15 min before reperfusion,dexmedetomidine 50 μg/kg was injected intraperitoneally in DP and DLP groups,while normal saline 0.5 ml was injected intraperitoneally in I/R and LP groups.In LP and DLP groups,the animals underwent 10 min ischemia of bilateral hind limbs starting from 10 min before reperfusion,followed by reperfusion.Blood samples were taken from the internal carotid artery at 180 min of reperfusion for determination of the plasma creatine kinase-MB (CK-MB) and glutathione peroxidase (GSH-Px) activities and the concentrations of cardiac troponin I (cTnI),malondialdehyde (MDA),interleukin-1beta (IL-1β),IL-6 and tumor necrosis factor-alpha (TNF-α).Myocardial specimens were obtained at 180 min of reperfusion for determination of the myocardial infarct size.Results Compared with group S,the plasma CK-MB activity,myocardial infarct size and plasma cTnI,MDA,TNF-α,IL-1β and IL-6 concentrations were significantly increased,and GSH-Px activity was significantly decreased in I/R,DP,LP and DLP groups (P＜0.05).Compared with group I/R,the plasma CK-MB activity,myocardial infarct size and plasma cTnI,MDA,TNF-α,IL-1β and IL-6 concentrations were significantly decreased,and the GSH-Px activity was significantly increased in DP,LP and DLP groups (P<0.05).Compared with DP and LP groups,the plasma CK-MB activity,myocardial infarct size and plasma cTnI,MDA,TNF-α,IL-1β and IL-6 concentrations were significantly decreased,and the GSH-Px activity was significantly increased in group DLP (P ＜ 0.05).Conclusion Dexmedetomidine postconditioning combined with limb ischemic postconditioning provides better efficacy than either alone in reducing the myocardial I/R injury in rats,and the mechanism may be related to the inhibition of lipid peroxidation and systemic inflammatory responses.
