Role of NO-cGMP-PKG signal transduction pathway in mitigation of myocardial ischemia-reperfusion injury by intrathecal morphine postconditioning in rats
10.3760/cma.j.issn.0254-1416.2014.05.009
- VernacularTitle:NO-cGMP-PKG信号转导通路在鞘内注射吗啡后处理减轻大鼠心肌缺血再灌注损伤中的作用
- Author:
Jun HU
;
Lingling JIANG
;
Shufang HE
;
Shiyun JIN
;
Weitian HE
;
Ye ZHANG
- Publication Type:Journal Article
- Keywords:
Nitric oxide;
Cyclic GMP;
Protein kinases;
Injections,spinal;
Morphine;
Myocardial reperfusion injury
- From:
Chinese Journal of Anesthesiology
2014;34(5):555-558
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the role of nitric oxide (NO)-cyclic guanosine monophosphate (cGMP)-protein kinase G (PKG) signal transduction pathway in mitigation of myocardial ischemia-reperfusion injury by intrathecal morphine postconditioning in rats.Methods Forty-eight male Sprague-Dawley rats in which intrathecal catheters were successfully placed without complications,weighing 250-350 g,were randomly assigned into 8 groups (n =6 each):normal saline group (NS group),morphine postconditioning group (Mp group),1-NG-nitroarginine methyl ester (L-NAME,NO synthase inhibitor) + morphine postconditioning group (L-NAME + MP group),ODQ (guanylate cyclase inhibitor) + morphine postconditioning group (ODQ + MP group),KT5823 (PKG inhibitor) + morphine postconditioning group (KT5823 + MP group),L-NAME group,ODQ group and KT5823 group.Myocardial ischemia was induced by 30 min of occlusion of anterior descending branch of left coronary artery followed by 2 h of reperfusion.At 25 rin of ischemia,normal saline 10 μl was intrathecally infused over 5 min in group NS,and morphine (3 μg/kg,10 μl) was intrathecally infused over 5 min in group MP.L-NAME (30 nmol,10 μl),ODQ (11 nmol,10 μl) and KT5823 (20 pmol,10 μl) were intrathecally injected at 10 rin before morphine postconditioning in L-NAME + MP,ODQ + MP and KT5823 + MP groups,respectively.Before myocardial ischemia (T0),at 25 and 30 min of ischemia (T1-2),and at 120 min of reperfusion (T3),MAP and HR were recorded,and rate-pressure product (RPP) was calculated.The rats were sacrificed at T3,and myocardial specimens were obtained for determination of myocardial infarct size as a percentage of area at risk (IS/AAR).Results MAP,HR and RPP were significantly lower at T1-3 than at T0 in each group.Compared with group NS,MAP was significantly increased at T3,and IS/AAR ratio was decreased in MP group,and no significant changes were found in the other groups.Compared with group MP,IS/AAR ratio was significantly increased in L-NAME + MP,ODQ + MP and KT5823 + MP groups,and no significant changes were found in the other groups.Conclusion NO-cGMP-PKG signal transduction pathway plays an important role in mitigation of myocardial ischemia-reperfusion injury by intrathecal morphine postconditioning in rats.
