Suttorp N, Galanos C, Neuhof H
Am J Physiol. 1987 Sep;253(3 Pt 1):C384-90. doi: 10.1152/ajpcell.1987.253.3.C384.
Endotoxin and lipid A dose dependently (1 ng/ml to 10 micrograms/ml) and time dependently (6-24 h) stimulated the generation of large amounts of prostacyclin in cultured pig pulmonary artery endothelial cells. This effect occurred in the absence of cell detachment and overt cell damage. The presence of at least 1% serum was required but the activation of the complement cascade was not. Endotoxin-treated endothelial cells generated increased amounts of prostacyclin upon stimulation with A23187 and arachidonic acid. Endotoxin-induced activation of arachidonate metabolism could be reduced by 10(-10) M glucocorticoids but not by progesterone. It was further affected by inhibitors of protein and RNA synthesis and calmodulin function. In addition, exposure of endothelial cells to endotoxin resulted in an enhanced synthesis of cyclooxygenase and in a higher enzymatic capacity of prostacyclin synthase. The data indicate that endotoxin in concentrations occurring in the plasma of patients profoundly alters arachidonic acid metabolism in endothelial cells.
内毒素和脂多糖以剂量依赖性方式（1纳克/毫升至10微克/毫升）和时间依赖性方式（6 - 24小时）刺激培养的猪肺动脉内皮细胞产生大量前列环素。这种效应在细胞未脱离且无明显细胞损伤的情况下发生。至少需要1%的血清存在，但补体级联反应的激活并非必需。经内毒素处理的内皮细胞在用A23187和花生四烯酸刺激后产生的前列环素量增加。内毒素诱导的花生四烯酸代谢激活可被10^(-10) M的糖皮质激素降低，但不能被孕酮降低。它还受到蛋白质和RNA合成抑制剂以及钙调蛋白功能抑制剂的影响。此外，内皮细胞暴露于内毒素会导致环氧化酶合成增加以及前列环素合酶的酶活性提高。数据表明，患者血浆中出现的内毒素浓度会深刻改变内皮细胞中的花生四烯酸代谢。
