[The effect of high density lipoprotein and oxidized high density lipoprotein on some secretive functions of endothelial cells].
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 5 mg/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.


CONCLUSIONS
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.
Li
Hong
H
Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Tang
Hui
H
Fang
Ding-Zhi
DZ
Liu
Bing-Wen
BW
D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D008075:Lipoproteins, HDL / Q000378:metabolism*; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D010084:Oxidation-Reduction; D010959:Tissue Plasminogen Activator / Q000096:biosynthesis; D014471:Umbilical Veins / Q000166:cytology* / Q000378:metabolism
D008075:Lipoproteins, HDL; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D010959:Tissue Plasminogen Activator