摘要
Abstract
Objective To investigate the effect of isoflurane preconditioning on myocardium after ischemia/reperfusion (I/R) injury in rats and its relation to toll-like receptor 4 (TLR4)/NF-κB signaling pathway.Methods Forty SD rats were randomly divided into five groups with 8 in each:sham-operated group (group S),ischemia/reperfusion group (group IR),isoflurane preconditioning group(group ISO),TAK-242 inhibitor group(group T) and isoflurane preconditioning and TAK-242 inhibitor group (group ISOT).The rats were given 1.0 MAC isoflurane inhalation for 30min before I/R induced;TLR4 receptor inhibitor TAK-242 10mg/kg was injected through tail vein 1 minute before inhaling isoflurane,and ischemic/reperfusion model was induced by ligation of anterior descending coronary artery.The myocardial tissue samples were obtained at the end of reperfusion.The size of myocardial infarction was measured by light microscope with HE staining.The expression of TLR4 mRNA and protein in myocardial tissue was detected by RT-PCR and Western blot,respectively,the expression of NF-κB was detected by Western blotting.Results Compared with group IR,the expression levels of TLR4 mRNA and protein was significantly lower in other groups (P＜0.01),compared with groups ISO and T,the expression of TLR4 mRNA and protein was down-regulated significantly (P＜0.01) in group ISOT,compared with group ISO,the expression of TLR4 mRNA and protein was down-regulated significantly (P＜0.01) in group T.Compared with group IR,the expression of NF-κB protein in other groups decreased significantly(P＜0.01),compared with groups T and ISOT,the expression of NF-κB protein in group ISO decreased significantly (P＜0.01).Compared with group IR,the size of myocardial infarction in other experimental groups were significantly reduced (P＜0.01),compared with group ISO and T,the infarct size was significantly reduced in group ISOT (P＜0.01),and there was no difference between group ISO and group T (P ＞0.05).Conclusion TLR4/NF-κ B signaling may be involved in protective effect of isoflurane preconditioning against myocardial ischemia-reperfusion injury in rats.关键词
缺血再灌注损伤/心肌保护/异氟醚/TLR4/NF-κBKey words
Ischemia reperfusion injury/Isoflurane/Myocardial preservation/Toll-like receptor 4/NF-κB
