氧化低密度脂蛋白诱导血管内皮细胞损伤的条件培养基对血管平滑肌细胞增殖的作用

目的观察氧化低密度脂蛋白（OX—LDL）损伤血管内皮细胞（VEC）的条件培养基对血管平滑肌细胞（VSMC）生长状态的影响。方法在培养的大鼠胸主动脉平滑肌细胞上，分别采用MTT染色法、流式细胞术及增殖细胞核抗原免疫组化方法等，检测OX—LDL诱导VEC损伤的条件培养基对VSMC生长率、细胞周期及PCNA表达的影响。结果OX—LDL可呈浓度依赖性损伤VEC的形态、减少上清液中NO含量、升高上清液中ET-1含量。终浓度为1001μg,／ml的ox-LDL与VEC共同孵育24h制备的条件培养基，能明显促进VSMC生长、提高PCNA表达及增加细胞周期S期细胞数。结论血管内皮细胞受到OX—LDL损伤时，制备的条件培养基能促进血管平滑肌细胞增殖，这可能是氧化低密度脂蛋白致动脉粥样硬化形成的原因之一。

The Effect of the Conditioned Medium of VEC Induced by ox-LDL on the Proliferation of VSMC

Objectives To observe the effect of the conditioned medium of VEC induced by ox- LDL on the growth of VSMC. Methods By using MTT staining, liquid cellular technique and the immune histochemistry method of the proliferous nucleus antigen respectively, the influence on the growth rate, cell cycle and PCNA expression of the cultured rat thoracic aorta smooth muscle cells caused by the conditioned medium leading to injury to VEC induced by ox-LDL were assayed. Results ox-LDL can injure the morphology of VEC in the form of reliance of the concentration, reduce the content of NO in the supernatant, and elevate the content of ET-1 in the supernatant. The conditioned medium which is prepared with the end concentration 100ug/ml of ox-LDL and VEC for 24 hours can obviously promote the growth of VSMC, increase the expression of PCNA and Phase S of the cellular cycle. Conclusion When the vascular endothelial cells are injured by ox-LDL, the prepared conditioned medium is able to promote the proliferation of VSMC. This may be one of the reasons for the formation of atherosclerosis induced by ox-LDL.