The presence of u-PA receptor in human endothelial cell and its regulation induced by PMA
- VernacularTitle:人血管内皮细胞存在尿激酶受体u-PA及PMA引起的受体调变
- Author:
Jun XING
;
Xuefeng REN
- Publication Type:Journal Article
- Keywords:
Urokinase;
Endothelium;
Human
- From:
Chinese Journal of Pathophysiology
1989;0(05):-
- CountryChina
- Language:Chinese
-
Abstract:
Urokinase-type plasminogen activator plays an important role in the dissolution of clot and the treatment of thrombosis diseases. Presently, more attention has been paid to urokinase metabolism in human body and the relationship between urokinase fibrolysis effect and its receptor in endothelial cell.Cultured endothelial cell was used in the experiment to react with labelled urokinase in the presence or absence of unlabelled urokinase. It was found that the specific bindind of labelled urokinase with endothelial cell increased with the increasing concentration of labelled urokinase and reached the saturation point from 10 to 32 ?g labelled urokinase/ ml. The maximal binding sites with urokinase per cell were 1.4?10?, and Kd value 7.5? 10~(-12)M, Meanwhile, PMA-treated endothelial cell was used to react with ~(125)I-uPA at the same conditions as discribed above. Compared with the specific binding of DMSO-treated endothelial ceil, the maximal binding sites per PMA-treated cell increased from 1.4?10~6 Per untreated cell to 2.2?10~6, and the Kd value from 7.5?10~(-12)M to 9?10~(-12)M.These results showed that urokinase receptor exists on the surface of endothelial cell, and that the number of receptor per cell could be modulated by PMA. It is possible that the urokinase binding with endothelial cell can play an important role in the very short half-life of urokinase in human body.
