天然及氧化修饰高密度脂蛋白对内皮细胞部分分泌功能的影响

The Effect of High Density Lipoprotein and Oxidized High Density Lipoprotein on Some Secretive Functions of Endothelial Cells

目的研究天然高密度脂蛋白(N-HDL)及氧化修饰高密度脂蛋白(OX-HDL)对培养人脐静脉内皮细胞(HUVEC)部分分泌功能的影响。方法采用培养人脐静脉内皮细胞,以0.01mol/LPBS为空白对照,以N-HDL为正常对照,分别加入不同质量浓度OX-HDL(5mg/L,10mg/L,50mg/L)共同孵育24h后,观察培养基中内皮细胞分泌一氧化氮(NO)、一氧化氮合酶(NOS)、组织型纤溶酶原激活物(tPA)和纤溶酶原激活物抑制剂(PAI-1)水平的变化。结果和空白对照相比,N-HDL组NO的量(P<0.05)和NOS活性(P<0.01)明显升高,tPA和PAI-1的差异没有统计学意义(P均>0.05);OX-HDL组NO的量和NOS活性均显著下降,并呈剂量依赖关系,PAI-1活性也显著升高(P<0.05),tPA的水平差异无统计学意义。结论N-HDL可以明显提高培养人脐静脉内皮细胞分泌NO的量并提高NOS活性,对tPA和PAI-1的产生则没有显著影响;而OX-HDL明显抑制内皮细胞NO合成和NOS活性,它不影响tPA的水平,却增加内皮细胞PAI-1活性。

Objective To investigate the effect of high density lipoprotein and oxidized high density lipoprotein on the synthesis of NO,the activity of NOS,and the secretion of tPA and PAI-1 by cultured human umbilical vein endothelial cells （HUVEC）. Methods With the 0. 01 mol/L PBS and N-HDL of 50 mg/L as control, OX-HDL of 5mg/L,10 mg/L,50 mg/L were co-incubated with HUVEC for 24 h in vitro. The levels of NO, the activity of NOS, and the levels of tPA and PAI-1 in the medium were detected after the incubation. Results Compared with the 0. 01 mol/L PBS control, the synthesis of NO（P〈0.05） and the activity of NOS（P〈0. 01） were significantly increased in the N-HDL group,but the change of tPA and PAI-1 displayed no statistical significance （both P〉0. 05）. In the OX-HDL group, the synthesis of NO and the activity of NOS were significantly decreased in a dose-dependent way; the PAI-1 activity（P〈0. 05） was increased, but the secretion of tPA（P〉0.05） was not affected. Conclusion N-HDL significantly increased the synthesis of NO and the activity of NOS secreted by HUVEC,but it had no influence on the generation of tPA and PAI-1. On the contrary,OX-HDL significantly decreased the synthesis of NO and the activity of NOS; it significantly increased PAI-1 activity , but had no effect on the secretion of tPA.