蛇床子素通过上调eNOS/PKG-1通路抗野百合碱所致大鼠肺动脉高压

Osthole inhibits monocrotaline-induced pulmonary arterial hypertension in rats via up-regulating eNOS/PKG-1 pathway

目的借助工具药N^(G)-硝基左旋精氨酸甲酯(L-NAME),探讨内皮型一氧化氮合酶(eNOS)/蛋白激酶G1(PKG-1)通路在蛇床子素(Ost)干预野百合碱(MCT)所致大鼠肺动脉高压(PAH)中的作用。方法在60只雄性Sprague-Dawley(SD)大鼠中随机抽取10只为正常对照组(Control组)。除Control组外,其余大鼠均采用颈背部一次性皮下注射MCT(55 mg/kg),建立PAH模型,并随机分为模型组(MCT组)、蛇床子素组(Ost组)、Ost+L-NAME组、L-精氨酸组(L-arg组)、L-arg+L-NAME组,后四组在建模第14天至第28天分别给予相应药物干预(qd)。在造模第28天,采用右心导管术检测大鼠肺动脉平均压(mPAP);称大鼠体重和肺组织重量,计算肺重指数(LI);H&E染色观察肺小动脉的形态学变化;蛋白免疫印迹法检测肺组织eNOS和PKG-1蛋白的表达。结果与Control组相比,MCT组大鼠肺动脉平均压和肺重指数均明显升高(P<0.05);肺小动脉血管壁增厚、管腔明显狭窄;肺组织eNOS与PKG-1蛋白表达均显著下调(P<0.05)。与MCT组相比,Ost组和L-arg组大鼠肺动脉平均压和肺重指数均明显下降(P<0.05);肺小动脉血管壁增厚、管腔狭窄的变化有所改善;肺组织eNOS与PKG-1蛋白表达均明显上调(P<0.05)。而给予L-NAME能明显拮抗Ost和L-arg的上述作用(P<0.05)。结论Ost改善野百合碱所致大鼠PAH的机制至少与上调eNOS/PKG-1通路有关。

Objective To investigate the role of eNOS/PKG-1 pathway in Osthole(Ost)intervention in pulmonary arterial hypertension induced by monocrotaline(MCT)in Sprague Dawley(SD)rats with the aid of the tool medicine,NOS inhibitor,L-NAME.Methods Sprague-Dawley(SD)rats(male,n=10)were randomly selected as the normal control group(control).Except for the control group,the other rats were injected with MCT(55 mg/kg)subcutaneously to establish PAH model.After 14 days,all the PAH rats were randomly divided into five groups,which were MCT group(MCT),Osthole group(Ost),Osthole+NOS inhibitor group(Ost+L-NAME),L-arginine group(L-arg),L-arginine+NOS inhibitor group(L-arg+L-NAME).After 14th days of modeling,the MCT group was given the equal volume of saline;while the rats in other groups were intervened with the above medicines respectively for 14 days for once a day.On 28th days of modeling,mean pulmonary artery pressure(mPAP)was detected by right heart catheterization;Body weight and lung weight were weighed and lung weight index(LI)was calculated;Morphology of the small pulmonary artery was observed by H&E;Protein expression of eNOS and PKG-1 in lung tissue was detected by Western blot.Results Compared with control group,mPAP and LI in MCT group were increased significantly(P<0.05);H&E staining showed that the pulmonary artery wall was thickened and the luminal stenosis was evident;the expression of eNOS and PKG-1 in lung tissue was significantly down-regulated(P<0.05).After administration of Ost and L-arg,mPAP and LI were decreased significantly(P<0.05);H&E staining showed that the pulmonary artery wall thickening and lumen stenosis were improved;the protein expression of eNOS and PKG-1 in lung tissue was significantly up-regulated(P<0.05).However,L-NAME treatment could inhibit the above effects of Ost and L-arg.Conclusion Osthole inhibits the monocrotaline-induced pulmonary arterial hypertension in rats,and the mechanism may be at least via up-regulating eNOS/PKG-1 pathway.