益气温阳活血化痰方对低氧高二氧化碳性肺动脉高压的作用及其机制

The effect of Yiqi Wenyang Huoxue Huatan Fang on hypoxia-hypercarbia induced pulmonary hypertension and its mechanism

目的:探讨益气温阳活血化痰方(YWHHF)经BMP-7/Smads通路抑制内皮-间质转分化(Endo MT),从而缓解低氧高二氧化碳性大鼠肺动脉压力的机制。方法:雄性健康清洁级SD大鼠50只,体重(180～220) g,随机分为5组(n=10):常氧组(N)、低氧高二氧化碳组(HH)、YWHHF高剂量组(YH)、中剂量组(YM)、低剂量组(YL)。N组在常氧环境下饲养,其余四组在低氧高二氧化碳(9%～11%O2、5%～6%CO2)环境下饲养4周,8 h/日,每周6d。YH、YM、YL组大鼠灌胃不同浓度的益气温阳活血化痰方(3 ml/kg),浓度分别为0.6、0.3和0.15 g/kg,HH组灌胃等体积生理盐水。4周后检测大鼠肺动脉平均压,肺灌流后取右心室游离壁及左心室加心室间隔测定右心室肥大指数。电镜观察肺超微结构变化,免疫荧光观察肺动脉结构变化,RT-PCR检测α-SMA、CD31、BMP-7、Smad1/5/8的mRNA水平,Western blot检测α-SMA、CD31、BMP-7、p-Smad1/5/8和Smad1/5/8的蛋白质水平。结果:与N组比,其余四组平均肺动脉压、右心室肥大指数均增大,镜下观察见肺有明显损伤,α-SMA mRNA及蛋白质表达升高,CD31、BMP-7、Smad1/5/8的mRNA水平降低,CD31、BMP-7、p-Smad1/5/8的蛋白质水平亦降低(P <0.05);与HH组比,中药组以上变化均有所减轻(P<0.05)。结论:YWHHF通过抑制Endo MT从而缓解肺动脉高压,其机制可能与促进BMP-7/Smads通路的表达有关。

Objective: To investigate the effect of Yiqi Wenyang Huoxue Huatan Fang( YWHHF) on alleviating hypoxia-hypercarbia pulmonary hypertension by inhibiting endothelial-mesenchymal transition( Endo MT) via BMP-7/Smads pathway. Methods:Fifty male healthy SD rats of clean grede,weighting( 180 ~ 220) g,were randomly divided into 5 groups( n = 10) : normoxia group( N),hypoxia-hypercarbia group( HH);YWHHF high dose group( YH),middle dose group( YM) and low dose group( YL). The rats in N group were kept in normal oxygen environment,the remaining four groups were intermittently exposed to hypoxia-hypercarbia environment( 9% ~ 11% O2,5% ~6% CO2) for 4 weeks,6 days a week,8 hours per day. The rats in YH,YM,YL groups were received YWHHF gavage in a dosageof 0.6,0.3,0.15 g/kg respectively( 3 ml/kg),the rats in N and HH groups were received equal volume of normal saline. After 4 weeks,the mean pulmonary arterial pressure( mPAP) was detected,the right ventricular free wall and left ventricle plus ventricular septum were isolated to determine the right ventricular hypertrophy index. Lung ultrastructural changes were surveyed under an electronic microscopy,the changes of pulmonary artery structure surveyed by immunofluorescence,the mRNA levels of alpha-smooth muscle actin( α-SMA) 、platelet endothelial cell adhesion molecule-1( CD31) 、bone morphogenetic protein-7( BMP-7) 、drosophila mothers against decapentaplegic protein1/5/8( Smad1/5/8) were detected by RT-PCR,and the protein levels of α-SMA、CD31、BMP-7、p-Smad1/5/8 and Smad1/5/8 were detected by Western blot. Results: Compared with N group,m PAP and the right ventricular hypertrophy index were increased,some significant injuries also were discovered under microscopic observation,the mRNA and protein expression of α-SMA was increased,and the mRNA expressions of CD31、BMP-7、Smad1/5/8 were decreased in the other four groups,the protein expressions of CD31、BMP-7、p-Smad1/5/8 were decreased( P<0.05). Compared with HH group,the above changes in YH、YM、YL groups were all improved( P<0.05). Conclusion: YWHHF can inhibit Endo MT to alleviate pulmonary hypertension,and the mechanism may be related to the promotion of the expression of BMP-7/Smads pathway.