Nuclear factor kappaB and anesthetic preconditioning during myocardial ischemia-reperfusion.
BACKGROUND
Volatile anesthetic preconditioning (APC) protects against myocardial ischemia-reperfusion (IR) injury, but the precise mechanisms underlying this phenomenon remain undefined. To investigate the molecular mechanism of APC in myocardial protection, the activation of nuclear factor (NF) kappaB and its regulated inflammatory mediators expression were examined in the current study.


METHODS
Hearts from male rats were isolated, Langendorff perfused, and randomly assigned to one of three groups: (1) the control group: hearts were continuously perfused for 130 min; (2) the IR group: 30 min of equilibration, 15 min of baseline, 25 min of ischemia, 60 min of reperfusion; and (3) the APC + IR group: 30 min of equilibration, 10 min of sevoflurane exposure and a 5-min washout, 25 min of global ischemia, 60 min of reperfusion. Tissue samples were acquired at the end of reperfusion. NF-kappaB activity was determined by electrophoretic mobility shift assay. The NF-kappaB inhibitor, IkappaB-alpha, was determined by Western blot analysis. Myocardial inflammatory mediators, including tumor necrosis factor alpha, interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase, were also assessed by Western blot analysis.


RESULTS
Nuclear factor kappaB-DNA binding activity was significantly increased at the end of reperfusion in rat myocardium, and cytosolic IkappaB-alpha was decreased. Supershift assay revealed the involvement of NF-kappaB p65 and p50 subunits. APC with sevoflurane attenuated NF-kappaB activation and reduced the expression of tumor necrosis factor alpha, interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase. APC also reduced infarct size and creatine kinase release and improved myocardial left ventricular developed pressure during IR.


CONCLUSIONS
The results of this study indicate that attenuation of NF-kappaB activation and subsequent down-regulation of NF-kappaB-dependent inflammatory gene expression plays an important role in the protective mechanism of APC against acute myocardial IR injury.
Zhong
Caiyun
C
Department of Anesthesiology and Pain Medicine, University of California, Davis, Davis, California 95817, USA.
Zhou
Yamei
Y
Liu
Hong
H
D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D015153:Blotting, Western; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003402:Creatine Kinase / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D007375:Interleukin-1 / Q000096:biosynthesis / Q000235:genetics; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology; D008861:Microsomes / Q000187:drug effects / Q000378:metabolism; D009203:Myocardial Infarction / Q000473:pathology; D017202:Myocardial Ischemia / Q000201:enzymology / Q000378:metabolism*; D015428:Myocardial Reperfusion Injury / Q000201:enzymology / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077149:Sevoflurane; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology
D018685:Anesthetics, Inhalation; D007375:Interleukin-1; D008738:Methyl Ethers; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D000077149:Sevoflurane; D004247:DNA; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D003402:Creatine Kinase