摘要
目的:探讨肾上腺髓质素(ADM)对血管紧张素Ⅱ(AngⅡ)诱导的血管外膜成纤维细胞(AF)迁移及胶原生成的影响及机制。方法:体外培养大鼠胸主动脉AF,运用Trans well技术测定不同浓度ADM对AF迁移的影响,采用酶联免疫吸附法(ELISA)测定培养上清中Ⅰ、Ⅲ型胶原蛋白含量,用RT-PCR及Western blotting分析AngⅡ(10-6mol/L)及不同浓度ADM干预后大鼠胸主动脉AF内骨桥蛋白(OPN)、转化生长因子β1(TGFβ1)mRNA及蛋白的表达。结果:在AngⅡ(10-6mol/L)趋化作用下,AF迁移数目较对照组显著增多[(30.26±1.08)∶(4.35±1.26),P<0.01]。ADM可抑制AngⅡ刺激的细胞迁移,迁移细胞数目在一定范围内随着ADM浓度增加而减少;AngⅡ(10-6mol/L)诱导OPN呈高表达,ADM可下调这种表达,呈一定剂量依赖性;AngⅡ显著增加培养上清中Ⅰ、Ⅲ型胶原蛋白含量,ADM呈剂量依赖的抑制AngⅡ上述作用,其中10-8mol/LADM组中Ⅰ、Ⅲ型胶原合成分别抑制了30%和31%(P<0.01),10-7mol/LADM组则分别抑制了43%和42%(P<0.01);ADM呈剂量依赖性抑制AngⅡ刺激的TGFβ1mRNA及蛋白表达,其中10-8mol/LADM组中TGFβ1mRNA及蛋白表达分别抑制了55%和45%(P<0.01),10-7mol/LADM组则分别抑制了70%和59%(P<0.01)。结论:ADM对AF的迁移及胶原生成无明显直接影响,但ADM可能通过下调细胞内OPN及TGFβ1表达,抑制AngⅡ诱导的血管AF迁移及胶原生成,从而发挥有效的抗血管重构作用。
Objective：To explore the effects of adrenomedullin （ADM）on AngⅡ-induced cell migration and collagen synthesis in cultured rat vascular adventitial fibroblasts. Method：Rat vascular adventitial fibroblasts were cultured in vitro.The effect of ADM on the migration of adventitial fibroblasts was evaluated by transwell,and the typeⅠ,Ⅲ collagen synthesis in adventitia fibroblasts was studied by ELISA. The expression of OPN and TGFβ1 in adventitial fibroblasts stimualted with ADM at different concentrations was measured by RT-PCR and Western blotting. Result：The stimulation of Ang-Ⅱaccelerated the adventitial fibroblasts migration obviously compared with the controls without the stimulaton（[30.26±1.08]vs[4.35±1.26],P〈0.01） ,while adrenomedullin could markedly inhibited the AngⅡ-induced migration of adventitial fibroblasts in a dose-dependent manner between 10^-7 and 10^-9mol/L,and it could also decline the expression of osteopontin these cells induced by AngⅡ,the effect of which paralleled with the inhibition of the cell migration.In addition,the AngⅡ induced type Ⅰand Ⅲ collagen secretion in adventitial fibroblasts was significantly reduced by adrenomedullin in a dose-dependent manner. And compared with AngⅡ group,the type Ⅰand Ⅲ collagen secretion decreased by 30% and 31% separately（P〈0.01） in adrenomedullin group at the concentration of 10^-8mol/L,and by 43% and 42% separately （P〈0.01） in adrenomedullin group at the concentration of 10^-7 mol/L. The similar changes were also found in the expression of TGFβ1 mRNA and protein.Compared with the AngⅡ group,the expression of TGFβ1 mRNA and protein decreased by 55% and 45% separately （P〈0.01） in adrenomedullin group at the concentration of 10^-8mol/L,and by 70% and 59% （P〈0.01） separately in adrenomedullin group at the concentration of 10^-7mol/L.Conclusion：ADM could inhibit AngⅡ induced cell migration and the type Ⅰ,Ⅲ collagen synthesis in adventitial fibroblasts,probably by reducing the expression of OPN and TGFβ1. It was suggested that ADM might play an important role in vascular remodeling as an antifibrotic factor.
出处
《临床心血管病杂志》
CAS
CSCD
北大核心
2010年第2期135-139,共5页
Journal of Clinical Cardiology
