中文摘要：

目的：探讨胡黄连苦苷Ⅱ（picroside-Ⅱ,P-Ⅱ）对心肌缺血再灌注（ischemia/reperfusion,I/R）损伤的保护作用及其对TLR4/NF-κB信号通路的影响。方法：30只成年雄性SD大鼠随机分为3组：假手术组（SO组）、缺血再灌注组（I/R组）、胡黄连苦苷Ⅱ＋缺血再灌注组（P-Ⅱ＋I/R组）。P-Ⅱ＋I/R组术前30min给予胡黄连苦苷Ⅱ（25mg/kg）尾静脉注射。除SO组外,其余2组大鼠均行冠状动脉左前降支结扎30min再灌注4h,建立心肌I/R损伤模型;使用试剂盒检测乳酸脱氢酶（LDH）、肌酸激酶（CK）的水平;HE染色观察心肌组织病理改变;TUNEL染色观察心肌细胞凋亡并计算凋亡率;蛋白免疫印迹法检测TLR4、NF-κB及IL-6和TNF-α的表达。结果：胡黄连苦苷Ⅱ预处理可显著降低LDH和CK的水平及心肌细胞凋亡率,差异有统计学意义（P〈0.05）;同时,缺血再灌注损伤中明显上调的TLR4、NF-κB以及IL-6、TNF-α蛋白表达水平均显著降低,差异有统计学意义（P〈0.05）。结论：胡黄连苦苷Ⅱ能够减轻大鼠心肌I/R损伤,这种保护作用可能与其抑制TLR4/NF-κB炎症信号通路密切相关。

英文摘要：

Objective：To investigate the protective effects of picroside-Ⅱ（P-Ⅱ）on myocardial ischemia/reperfusion（I/R）injury and its influence on TLR4/NF-κB signaling pathway.Method：Thirty adult male SD rats were randomly divided into three groups：sham-operated group（SO group）,I/R group and P-Ⅱ＋I/R group（P-Ⅱ＋I/R group）.P-Ⅱ（25mg/kg）was injected via tail vein before operation.I/R injury was prepared by coronary artery ligation for 30 min followed by 4hours of reperfusion in rats.Lactate dehydrogenase（LDH）and creatine kinase（CK）were measured with kits;the pathologic changes of myocardial tissue was observed by HE staining,TUNEL-positive cells were calculated to assess myocardial apoptosis index.Western blotting was performed to measure the expression of TLR-4,NF-κB and IL-6,TNF-α.Result：P-Ⅱ significantly decrease the level of LDH and CK,in addition,the myocardial apoptosis index was reduced（P〈0.05）;Meanwhile,P-Ⅱsignificantly downregulated the expression of TLR-4,NF-κB and IL-6,TNF-α（P〈0.05）.Conclusion：P-Ⅱcould alleviate myocardial ischemia/reperfusion injury and the protective effect may relate to the inhibition of TLR-4/NF-κB signaling pathway.