低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素的影响

Effect of low density lipoprotein and oxidized low density lipoprotein on the synthesis of adrenomedullin in cultured endothelial cells

目的探讨低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素(ADM)的影响。方法利用培养的内皮细胞株ECV-304细胞,分别与不同浓度的低密度(50 100 mg/L)、氧化低密度脂蛋白(50 100 mg/L)及低密度脂蛋白(50 mg/L)+氧化低密度脂蛋白(50 mg/L)进行孵育,24 h后分别收集培养上清及细胞,用放免分析检测上清及细胞内肾上腺髓质素的含量。结果低密度脂蛋白对肾上腺髓质素的分泌无影响,而氧化型低密度脂蛋白能明显刺激ADM的分泌,二者合用的作用接近于100 mg/L的OX-LDL。结论OX-LDL可能具有氧化LDL使其成为OX-LDL的作用,ADM的分泌可能是对细胞损伤的一种反应。

Objective: To investigate the effect of low density lipoprotein (LDL) and oxidized low density lipoprotein (OX-LDL) on the synthesis of adrenomedullin in cultured endothelial cells. Methods: Endothelial cells incubated with different concentration of LDL (50,100 mg/l), OX-LDL (50,100 mg/l) or LDL (50 mg/l) in combination with OX-LDL (50 mg/l) for 24 hours, then collected the cells and the cultured medium. Radioimmunoassay was conducted to evaluate the content of ADM in the cells and the level of ADM in the cultured medium. Results: OX-LDL enhanced the synthesis of ADM, and LDL in combination with OX-LDL had a greater effect than any of the two lipoprotein`s. Conclusions: OX-LDL may have the ability to oxide LDL and make LDL to be OX-LDL, the synthesis of ADM enhanced by OX-LDL may be a response of cell itself to injury.