肝肺综合征大鼠肺微血管内皮细胞肌样分化时转化生长因子β1表达的变化

目的 评价肝肺综合征(HPS)大鼠肺微血管内皮细胞(PMVECs)肌样分化时转化生长因子β1 (TGF-β1)表达的变化.方法 健康SD大鼠40只,雌雄不拘,3～4月龄.采用随机数字表法,随机取20只大鼠,采用慢性胆总管结扎法制备HPS模型,剩余大鼠行假手术,取腹主动脉血样4ml,离心后取血清.另取健康成年SD大鼠10只,原代培养、纯化及鉴定PMVECs.PMVECs接种于低糖DMEM培养基(106个/cm2),采用随机数字表法,将细胞随机分为2组:对照组(C组)和HPS组,每组24皿.C组给予正常大鼠血清,HPS组加入HPS大鼠血清,血清终浓度为10％.于细胞孵育24h(T1)、48 h(T2)和72 h(T3)时分别采用RT-PCR法和Western blot法测定PMVECs内平滑肌肌球蛋白重链(SM-MHC)、平滑肌肌动蛋白α(SM-α-actin)、肌钙蛋白、TG F-β1 mRNA及其蛋白的表达.结果 C组PMVECs内SM-α-actin、肌钙蛋白表达阴性,可见少量SM-MHC表达,HPS组PMVECs内SM-MHC、SM-α-actin、肌钙蛋白表达阳性.与C组比较,HPS组SM-MHC、TGF-β1 mRNA及其蛋白的表达上调(P＜0.05)；与T1时比较,T2.3时HPS组SM-MHC、SM-α-actin、肌钙蛋白、TGF-β1 mRNA及其蛋白的表达上调(P＜0.05)；与T2时比较,T3时HPS组SM-MHC、SM-α-actin、肌钙蛋白、TG F-β1 mRNA及其蛋白的表达上调(P＜0.05).结论 TGF-β1在HPS大鼠PMVECs肌样分化时可能起到重要的调控作用.

Changes in expression of transforming growth factor beta-1 during myogenic differentiation of pulmonary microvascular endothelial cells in rats with hepato-pulmonary syndrome

Objective To investigate the changes in the expression of transforming growth factor beta-1 (TGF-β1) during differentiation of pulmonary microvascular endothelial ceils (PMVECs) into smooth muscle cells in rats with hepato-pulmonary syndrome (HPS).Methods Primary PMVECs were harvested from healthy adult SD rats of both sexes aged 3-4 months and inoculated in low-glucose DMEM culture medium (1(6/cm2 ) and randomly divided into 2 groups ( n =24 dishes each):control group ( group C) and HPS group.HPS was produced by chronic ligation of common bile duct.In group C serum obtained from normal rats was added to PMVECs,while in HPS group serum obtained from rats with HPS was added.The final concentration of serum was 10％.After being incubated for 24,48 and 72 h,the expression of SM-MHC,SM-α-actin and calponin protein and TGF-β1 mRNA and protein in PMVECs was determined by RT-PCR and Western blot analysis.Results The expression of SMMHC,SM-α-actin and calponin protein.was positive in HPS group whereas the expression of SM-α-actin and calponin protein was negative and the expression of SM-MHC protein was barely detectable in group C.The expression of SM-MHC,TGF-β1 mRNA and protein was significantly higher in HPS group than in group C.The expression of SM-MHC,SM-α-actin and calponin protein and TGF-β1 mRNA and protein was increasing with duration of incubation from T1 to T3 in group HPS.Conclusion TGF-β1 plays an important role in the myogenic differentiation of PMVECs in rats with HPS.