Sanders R L, Engle M J, Douglas W H
Biochim Biophys Acta. 1981 May 22;664(2):380-8. doi: 10.1016/0005-2760(81)90060-6.
Organotypic cultures of pulmonary type II epithelial cells were treated with dexamethasone at concentrations between 10(-10) and 10(-5) M for 48 h followed by a 3 h incubation in 5.6 mM [U-14C]glucose. A surfactant and a residual fraction was isolated from the cultures by discontinuous sucrose gradient centrifugation. Phosphatidylcholine and phosphatidylglycerol were purified from each fraction and analyzed for total content. The specific activity of each phospholipid was measured as an index of the rate of synthesis. Dexamethasone treatment produced a dose-dependent increase in synthesis and content of surfactant phosphatidylcholine, with a maximum response occurring at 10(-6) M dexamethasone. At concentrations of 10(-5) M, dexamethasone ceased to produce a significant stimulation. Dexamethasone produced an increase in surfactant phosphatidylglycerol synthesis only at a concentration of 10(-8) M and higher. There was not a significant effect upon the content or rate of synthesis of phosphatidylcholine or phosphatidylglycerol in the residual fraction at any of the dexamethasone concentrations tested.
将肺II型上皮细胞的器官型培养物用浓度在10^(-10)至10^(-5) M之间的地塞米松处理48小时，然后在5.6 mM [U-14C]葡萄糖中孵育3小时。通过不连续蔗糖梯度离心从培养物中分离出表面活性剂和残留部分。从每个部分中纯化磷脂酰胆碱和磷脂酰甘油，并分析其总含量。测量每种磷脂的比活性作为合成速率的指标。地塞米松处理使表面活性剂磷脂酰胆碱的合成和含量呈剂量依赖性增加，在地塞米松浓度为10^(-6) M时出现最大反应。在10^(-5) M的浓度下，地塞米松不再产生显著刺激。地塞米松仅在浓度为10^(-8) M及更高时才使表面活性剂磷脂酰甘油的合成增加。在所测试的任何地塞米松浓度下，对残留部分中磷脂酰胆碱或磷脂酰甘油的含量或合成速率均无显著影响。
