【摘要】 目的:观察低氧时肾上腺髓质素(adrenom edu llin,ADM)对人胚肺成纤维细胞增殖和胶原合成的影响,以阐明ADM在低氧性肺血管结构改建过程中可能发挥的作用,为研究防治低氧性肺动脉高压的途径提供新的思路和实验依据。方法:采用体外细胞培养方法,建立人胚肺成纤维细胞低氧(2%O2)模型;在培养细胞中加入不同浓度的ADM,按24、48及72 h进行培养;采用细胞计数、四氮唑盐(MTT)法、3H-脯氨酸掺入法,分别观察不同浓度ADM及不同时间的低氧对成纤维细胞增殖及胶原合成与分泌的影响,并与常氧组进行对照。结果:原代培养人胚肺成纤维细胞免疫组化染色α-actin阴性,证明本实验所培养的细胞是成纤维细胞。低氧24、48及72 h组均明显促进成纤维细胞增殖和胶原合成与分泌,与对照组比较,差别有非常显著性意义(P<0.01)。低氧各组加入ADM后,成纤维细胞增殖受到抑制(P<0.05),以ADM10-7mol/L组抑制作用最明显。低氧24、48及72 h均明显促进成纤维细胞胶原合成与分泌(P<0.01)。低氧各组加入ADM后,成纤维细胞胶原合成与分泌受到抑制(P<0.05,P<0.01),以ADM10-7mol/L组抑制作用最明显。结论:低氧可诱导肺成纤维细胞增殖、胶原合成和分泌增加,ADM可以抑制低氧引起的肺成纤维细胞增殖和胶原合成,提示ADM具有抑制低氧性促肺血管重塑效应。更多还原

【Abstract】 Objective:To investigate the impacts of adrenomedullin（ADM） on proliferation and collagen synthesis of human fetal lung fibroblasts under hypoxia（2%O₂）in order to find out the potential role of ADM in vascular reconstruction of lung under hypoxia.Methods:Human fetal lung fibroblasts were cultured in vitro.A stable model of fibroblasts under hypoxia（2%O₂）was established.During the culture,the fibroblasts were exposed to hypoxia（2%O₂） in various concentrations of ADM 10^-9,10^-8,10^-7mol/L in the media for 24,48 and 72 hours,respectively.The effects of ADM on proliferation of fibroblasts were determined by manual cell counting under the microscope and MTT assay.Total collagen synthesis and secretion were detected by ³H-proline incorporation assay.Results:Staining for α-actin in fibroblasts on primary culture were negative,indicating that the cells in this culture were definitely human fetal lung fibroblasts.Compared with exposure to normoxia,cell number and 490 nm OD significantly increased after exposure to 2% hypoxia for 24,48 and 72 h,respectively（P<0.01）.In hypoxia exposure group,when ADM was added to the media,the proliferation of fibroblasts was suppressed（P<0.05）.The most inhibitive effect was obtained at ADM concentration of 10^-7mol/L.An obvious increase of collagen synthesis and secretion were detected after 2% hypoxia exposure for 24,48 and 72 h.ADM(10^-7mol/L)could inhibit the proliferation and synthesis of collagen by fibroblasts under hypoxia.Conclusions:Hypoxia could induce the proliferation of fibroblasts,and the synthesis and secretion of collagen;ADM would inhibit this process.This suggested that ADM might restrain the pulmonary vascular structural remodeling induced by hypoxia.更多还原