中药复方对流感病毒性肺炎小鼠肺血管通透性的影响及机制

摘要

目的 观察经典合方犀角(水牛角)地黄汤合银翘散对流感病毒感染致病毒性肺炎小鼠肺血管通透性的影响,并探讨其作用机制.方法 BALB/c小鼠216只随机分为3组,正常组、模型组、药物组,25 μL 50LD50病毒液滴鼻建立流感病毒鼠肺适应株感染的小鼠肺炎模型(除正常组外),感染后1h,正常组和模型组予以双蒸水灌胃；药物组予中药23 g/( kg·d)灌胃；各组均给药2次/d,连续给药5d.感染后的2、4、6d,处死小鼠,取肺组织称重以检测肺指数、肺含水量；1％伊文氏兰5 mL/kg尾静脉注射检测肺血管通透性；放免法测定肺组织中前列腺素:(PGE2:)和磷脂酶A2( PLA2)含量,酶免法测定肺组织中白三烯B4(LT-B4)含量；RT-PCR检测肺组织中水通道蛋白( AQP-1)的mRNA水平.结果 病毒感染后,模型组肺指数、肺含水量持续升高,犀角(水牛角)地黄汤合银翘散在第4、6天明显降低了肺指数(P＜0.01,P＜O.01),在第6天时降低了肺含水量(P＜0.05)；模型组肺血管通透性在感染后第4天和第6天均明显升高,犀角(水牛角)地黄汤合银翘散明显降低了肺血管通透性(P＜0.01).感染后,模型组肺组织中PGE2、PLA2、LT-B4的含量均明显升高,犀角(水牛角)地黄汤合银翘散不同程度地抑制了PGE2、PLA2、LT-B4的产生；与正常组比较,模型组AQP-1 mRNA在第4天、第6天时较低(P＜0.01),犀角(水牛角)地黄汤合银翘散组在第6天时AQP-1 mRNA含量较模型组高,差异有显著性(P＜0.01).结论 犀角(水牛角)地黄汤合银翘散通过抑制流感病毒感染后肺组织中PGE2、PLA2、LT-B4的释放,提高AQP-1的表达,从而降低了肺血管通透性,对病毒性肺炎中肺水肿的形成,起到改善作用.%Objective To observe the influence of Xijiao ( Shuiniujiao) Dihuang Tang combining Yinqiao San, a classic combined formula, on the lung vascular permeability in mice with viral pneumonia induced by influenza virus, and to discuss the mechanism. Methods BALB/c mice (n =216) were randomly divided into the normal group, model group and medicinal group. The mouse model of pneumonia infected by influenza virus lung-adapted strain was established by using nasal drip of 50 LD50 virus liquid (25 μL). After one hour the normal group and model group were given double distilled waterintragastrically, and the medicinal group was given Xijiao ( Shuiniujiao) Dihuang Tang combining Yinqiao San (23 g/kg · D) twice a day for 5 days. All mice were killed and the lung tissue was collected for weighing and detecting lung index and water content 2, 4 or 6 days after infection. The lung vascular permeability was detected by injecting 1% Evans blue (5 mL/kg) in mouse caudal vein. The content of prostaglandin E2 ( PGE2 ) and phospholipase A2 ( PLA2 ) were determined by using radioimmunoassay, the content of leukotrienes B4( LT-B4) was detected by using enzyme-linked immunosorbent assay (ELISA) , and the mRNA level of aquaporin-1 (AQP-1) in lung tissue was detected by using reverse transcription polymerase chain reaction (RT-PCR). Results After virus infection, the lung index and water content increased continuously in the model group. The lung index decreased significantly (P <0. 01, P <0. 01) on the 4th and 6th day, and the lung water content decreased on the 6th day (P < 0. 05) after the administration of Xijiao ( Shuiniujiao) Dihuang Tang combining Yinqiao San. The lung vascular permeability increased significantly in the model group on the 4th and 6th day after the infection, and decreased significantly ( P < 0. 01 ) after the administration of Xijiao ( Shuiniujiao) Dihuang Tang combining Yinqiao San. The content of PGE2, PLA2 and LT-B4 increased significantly in the model group and Xijiao (Shuiniujiao) Dihuang Tang combining Yinqiao San inhibited the producing of PGE2, PLA2 and LT-B4. Compared with the normal group, in the model group the level of AQP-1 mRNA was lower on the 4th and 6th day (P <0.01) , while in the medicinal group, it was higher on the 6th day than that in the model group (P<0.01). Conclusion Xijiao (Shuiniujiao) Dihuang Tang combining Yinqiao San can ameliorate the pulmonary edema during viral pneumonia through inhibiting the release of PGE2, PLA2 and LT-B4, improving AQP-1 expression, and reducing lung vascular permeability.