Effect of multiple doses of endotoxin on production of nitric oxide by endothelial cells
- Author:
Peng LI
;
Shanshan LI
;
Qifu HUANG
- Publication Type:Journal Article
- From:
Chinese Journal of Pathophysiology
2001;17(8):780-
- CountryChina
- Language:Chinese
-
Abstract:
To study the direct effect of E.Coli endotoxin on the production of nitric oxide by endothelial cells, the second passage of cultured human umbilical cells was stimulated by serial doses of endotoxin (1 g/L, 10 mg/L, 100 μg/L, 10 μg/L, 1 μg/L), and the content of nitric oxide in supematant of culture and the viability of endothelial cells 6 hours after the stimulation were obcerved. The result showed that endotoxin had a slightly inhibitory effect on both the production of nitric oxide and the viability of endothelial cells at low doses (1 μg/L, 10 μg/L, 100 μg/L), especially the dose of 100 μg/L ［(608.63±11.64) μmol/L, versus that of unstimulated grouop (629.46±13.36) μmol/L, P＜0.05］. While the high doses of endotoxin exerted a big increasing in production of nitric oxide and a big decrease in the viability of endothelial cells, especially the dose of 1 g/L (NO: 722.58 μmol/L±32.18 μmol/L, versus that of unstimulated group P＜0.01; viability: 73.63%±8.50%, versus that of unstimulated group, P＜0.01). These could be concluded that low doses of endotoxin mainly resulted in functional changes in endothelial cells, such as decrease in relaxing factor (nitrc oxide), while high doses endotoxin exerted lethal effects on endothelial cells accompanied with high production of nitric oxide, which might be related to the death of cells.
