Niu X L, Yan X D, Guo Z G
Laboratory of Molecular Pharmacology, Hunan Medical University, Changsha, China.
Zhongguo Yao Li Xue Bao. 1997 Jan;18(1):59-62.
To study the effects of oxidized low-density lipoproteins (ox-LDL) on the adhesiveness of monocytes to endothelial cells.
LDL was obtained from healthy human plasma by ultracentrifugation, and oxidized by CuSO4 10 mumol.L-1. The assay of adhesion was performed using cultured bovine aortic endothelial cells (BAEC) and human peripheral blood monocytes.
Pretreatment BAEC with ox-LDL enhanced monocyte adhesion to BAEC in time- and dose-dependent manner. ox-LDL as little as 10 mg.L-1 and 30 min of preincubation stimulated monocyte adhesion. Cycloheximide (Cyc, a protein synthesis inhibitor) 1 mg.L-1 and staurosporine (Sta, a PKC inhibitor) 20 nmol.L-1 abolished the effect of ox-LDL (60 mg.L-1), but dextran sulfate 20 mg.L-1 had no effect on monocyte adhesion. Phorbol 12-myristate 13-acetate (PMA) 1 nmol.L-1 and lysophosphatidylcholine (Lys) 6 mumol.L-1 mimicked the effects of ox-LDL and potentiated monocyte adhesion. Sta also suppressed the augmentative effects of Lys and PMA.
ox-LDL enhances the adhesion of monocytes to BAEC through the activation of PKC.
研究氧化型低密度脂蛋白（ox-LDL）对单核细胞与内皮细胞黏附性的影响。
通过超速离心从健康人血浆中获取低密度脂蛋白（LDL），并用10 μmol.L-1的硫酸铜将其氧化。使用培养的牛主动脉内皮细胞（BAEC）和人外周血单核细胞进行黏附试验。
用ox-LDL预处理BAEC可使单核细胞与BAEC的黏附呈时间和剂量依赖性增强。低至10 mg.L-1的ox-LDL和30分钟的预孵育即可刺激单核细胞黏附。1 mg.L-1的环己酰亚胺（Cyc，一种蛋白质合成抑制剂）和20 nmol.L-1的星形孢菌素（Sta，一种蛋白激酶C抑制剂）可消除ox-LDL（60 mg.L-1）的作用，但20 mg.L-1的硫酸葡聚糖对单核细胞黏附无影响。1 nmol.L-1的佛波醇12-肉豆蔻酸酯13-乙酸酯（PMA）和6 μmol.L-1的溶血磷脂酰胆碱（Lys）模拟了ox-LDL的作用并增强了单核细胞黏附。Sta也抑制了Lys和PMA的增强作用。
ox-LDL通过激活蛋白激酶C增强单核细胞与BAEC的黏附。
