基于磷酸肌醇3-激酶/蛋白激酶B/一氧化氮合酶通路探讨灯盏花素对阵发性心房颤动大鼠的作用

Effect of breviscapine on myocardial pathological injury in rats with paroxysmal atrial fibrillation based on phosphoinositide 3-kinase/protein kinase B/nitric oxide synthase pathway

目的研究灯盏花素对阵发性心房颤动(paroxysmal atrial fibrillation,PAF)大鼠的作用及其与磷酸肌醇3-激酶(phosphoinositide 3-kinase,PI3K)/蛋白激酶B(protein kinase B,Akt)/内皮型一氧化氮合酶(endothelium nitric oxide synthase,eNOS)信号通路的相关机制。方法大鼠尾静脉注射乙酰胆碱+氯化钙建立PAF模型,并随机分为模型组、对照组和低、中、高剂量实验组;另取20只健康SD大鼠作为空白组。对照组按5 mL·kg^(-1)的剂量给予4 mg·mL^(-1)稳心溶液,qd;低、中、高剂量实验组均按5 mL·kg^(-1)的剂量分别给予4,8和16 mg·mL^(-1)灯盏花素溶液,qd;空白组和模型组均灌胃给予等体积0.9%NaCl,qd。6组大鼠连续给药4周。用实时荧光定量聚合酶链反应检测心肌组织中PI3K、Akt和eNOS mRNA的表达水平,用心电图和激光散斑实时成像系统检测心房颤动持续时间与心脏表面平均血流灌注量(perfusion,PU)。结果低、高剂量实验组和对照组、模型组、空白组的PI3K mRNA分别为1.69±0.17,2.63±0.20,2.69±0.19,0.98±0.12和3.01±0.17,Akt mRNA分别为1.81±0.18,2.73±0.11,2.83±0.12,0.56±0.13和3.26±0.11,eNOS mRNA分别为1.97±0.18,2.61±0.20,2.62±0.19,0.57±0.19和3.19±0.21,心房颤动持续时间分别为(23.05±0.94),(3.15±0.59),(3.10±0.72),(49.65±14.01)和0 s,PU分别为(399.45±6.95),(489.65±12.78),(523.75±8.33),(367.85±6.94)和(585.75±6.48)mL·min^(-1)。低、高剂量实验组和对照组、空白组大鼠的上述指标与模型组比较,差异均有统计学意义(均P<0.05)。结论灯盏花素对PAF心肌病理性损伤具有明显的保护作用,其机制与灯盏花素促进PI3K/Akt/eNOS通路表达,进而抑制炎症因子的表达有关。

Objective To study the effect of breviscapine on rats with paroxysmal atrial fibrillation(PAF)and its related mechanism with phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt)/endothelium nitric oxide synthase(eNOS)signaling pathway.Methods Rats were injected with acetylcholine+calcium chloride into the tail vein to establish a PAF model,and were randomly divided into model group,control group and experimental-L,-M,-H groups;another 20 healthy SD rats were taken as blank group.The control group was treated with 4 mg·mL^(-1)Wenxin solution 5 mL·kg^(-1),qd;the experimental-L,-M,-H groups were treated with 4,8,16 mg·mL^(-1)breviscapine solution 5 mL·kg^(-1),qd;the blank group and the model group were given an equal volume of 0.9%NaCl,qd,by intragastric administration for 4 weeks.Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression levels of myocardial tissue PI3K,Akt and eNOS mRNA,and the electrocardiogram and laser speckle real-time imaging system were used to detect the duration of atrial fibrillation and the average blood perfusion(PU)on the surface of the heart.Results The PI3K mRNA in the experimental-L,-H groups,control group,model group and blank group were 1.69±0.17,2.63±0.20,2.69±0.19,0.98±0.12 and 3.01±0.17,Akt mRNA were 1.81±0.18,2.73±0.11,2.83±0.12,0.56±0.13 and 3.26±0.11,eNOS mRNA were 1.97±0.18,2.61±0.20,2.62±0.19,0.57±0.19 and 3.19±0.21,duration of atrial fibrillation were(23.05±0.94),(3.15±0.59),(3.10±0.72),(49.65±14.01)and 0 s,PU were(399.45±6.95),(489.65±12.78),(523.75±8.33),(367.85±6.94)and(585.75±6.48)mL·min^(-1),respectively.Compared with the model group,the above indicators of the experimental-L,-H groups,control group and blank group were statistically different(all P<0.05).Conclusion Breviscapine has a significant protective effect on myocardial pathological damage in paroxysmal atrial fibrillation,and its mechanism is related to breviscapine promoting the expression of PI3K/Akt/eNOS pathway and inhibiting the expression of inflammatory cytokines.