尼氟灭酸抑制跨膜蛋白16A参与高肺血流量诱导的肺动脉高压的机制研究

Study on mechanism of niflumic acid inhibiting the involvement of transmembrane protein 16A in pulmonary artery hypertension induced by high pulmonary blood flow

目的:探讨钙激活的氯离子通道(CaCCs)抑制剂尼氟灭酸(NFA)和跨膜蛋白16A(TMEM16A)在高肺血流量诱导的肺动脉高压(PAH)中的作用及机制。方法:将40只SD大鼠随机分为normal组、sham组、model组及model+NFA组,sham组使用血管夹夹闭腹主动脉15 min,model组采用腹主动脉—下腔静脉造瘘术建立左向右分流型PAH模型,model+NFA组在造瘘术后予NFA进行每日灌胃;饲养12周后,检测大鼠平均肺动脉压、肺动脉血管张力,并采用实时荧光定量PCR和蛋白质免疫印迹法(western blotting)检测各组肺动脉平滑肌细胞(PASMCs)TMEM16A的表达。结果:model组和model+NFA组大鼠肺动脉环收缩率及TMEM16A m RNA和蛋白表达水平显著高于normal组(P<0.05)。与model组比较,model+NFA组大鼠TMEM16A mRNA和蛋白表达水平降低,肺动脉环收缩率下降(P<0.05)。结论:高肺血流量诱导的PAH与TMEM16A高表达有关,NFA可以降低肺动脉血管张力,抑制TMEM16A的过表达。

Objective:To explore the role and potential mechanism of niflumic acid(NFA),a calcium-activated chloride channel(CaCCs)inhibitor,and transmembrane protein 16A(TMEM16A)in the pulmonary artery hypertension(PAH)induced by high pulmonary blood flow.Methods:Forty SD rats were randomly divided into normal group,sham group,model group and model+NFA group.The sham group was used vascular clamp to clamp the abdominal aorta for 15 minutes,the model group was used abdominal aorta-inferior vena cava fistulation to establish a left-to-right shunt PAH model,and the model+NFA group was given NFA by gavage daily after fistulation.After feeding for 12 weeks,the mean pulmonary artery pressure and pulmonary artery tension of rats were measured,and the expression of TMEM16A in pulmonary artery smooth muscle cells(PASMCs)of each group was detected by reverse transcription-quantitative PCR(RT-qPCR)and western blotting.Results:The contraction rate of pulmonary artery ring,TMEM16A mRNA and protein expression levels in the model group and model+NFA group were significantly higher than those in the normal group(P<0.05).Compared with the model group,the TMEM16A mRNA and protein expression level in the model+NFA group was down-regulated and the contraction rate of pulmonary artery ring was decreased(P<0.05).Conclusion:PAH induced by high pulmonary blood flow is related to the high expression of TMEM16A.NFA can reduce pulmonary artery tension and inhibit the overexpression of TMEM16A.