黄芪对急性呼吸窘迫综合征大鼠模型肺组织中SP-A的影响

Effects of AM on SP-A in rats with ARDS

目的:研究黄芪对急性呼吸窘迫综合征(Acute Respiratory Distress Syndrome,ARDS)大鼠肺组织中肺表面活性蛋白A(Surfactant Protein,SP)表达的影响,并探讨其可能的机制。方法:SPF级Wistar大鼠60只,随机分为正常对照组(Normal Saline,NS组)、模型组(Model Group,MG组)、黄芪高剂量组(large does of astragalus membrana ceous)、黄芪中剂量组(middle does of astragalus membranaceous)、黄芪低剂量组(small does of astragalus membrana ceous)、地塞米松组(Dexamethasone,DEX组)。通过静脉内注射油酸(Oleic Acid,OA)0.1mlkg-1建立大鼠模型,利用光镜观察肺部组织形态学变化,计算肺系数(Lung Index,LI),酶联免疫吸附法(ELISA)测定血清中SP-A含量,采用实时荧光定量PCR法检测肺组织SP-AmRNA表达情况。结果:黄芪高、中剂量能提高血清SP-A含量(P<0.01),降低肺系数(P<0.01),增强肺组织SP-AmRNA表达(P<0.05),减轻肺组织病理损伤。黄芪低剂量的效果不如高、中剂量(P<0.05)。结论:黄芪能够明显减轻油酸所致ARDS的炎症反应,其药理作用机制与上调肺内ARDS的表达,从而刺激肺泡II上皮细胞(II alveolar epithelial type cells,AEC II)增生有关。

Objective： To explore the effect and mechanism of astragalus membranaceous （AM） on acute respiratory distress syndrome （ARDS） rat induced by OA. Methods： 60 SPF Wistar rats were randomly divided into 6 groups, control group, model group, large does of astragalus membranaceus group, middle does of astragalus membranaceus group, small does of astragalus membranaceus group and dexamethasone group. A rat model of ALI was established by intravenous injection of oleic acid with a does of 0. lml kgl. Light microscope was used to examine histological changes and lung index was calculated by weighting method. SP-A levels in serum were determined using commercial enzyme-linked immunosorbent assay kits. The expression of SP-A genes by real-time PCR. Results： Large does of astragalus membranaceus group and middle does of astragalus membranaceus group improved the production of SP-A in whole blood （P〈0.01）, reduced the lung index （P〈0.01） and intensified SP-AmRNA expression （P〈0.05） as compare with the model group. Pathological changes of ARDS were reduced significantly in astragalus membranaceus intervention groups, small does of astragalus membranaceus group was lower than the effect of large does of astragalus membranaceus group and middle does of astragalus membranaceus group （P〈0.05）. Conclusion： Astragalus membranaceous could alleviate oleic acid induced acute respiratory distress syndrome in rats, and its pharmacological action mechanism may be related to raise the lungs SP-A expression, so as to stimulate II alveolar epithelial type cells （AEC II） proliferation.