[Effects of homocysteine on human vascular endothelial cells, platelet aggregation and heparin cofactor activity].
OBJECTIVE
To elucidate partly the mechanism of homocysteine-associated thrombosis.


METHODS
1. Thrombomodulin (TM) antigen distribution on human vascular endothelial cell (EC) membrane was assayed by immune-fluorescence histochemistry stain and flow cytometry; 2. Plasma heparin cofactor activity was measured by chromogenic method.


RESULTS
Homocysteine (Hcy) significantly down-regulated the expression of TM on EC, with a concentration-dependent manner; 2. Hcy did not influence platelet aggregation induced by ADP and thrombin; 3. Hcy exerted no effects on the activities of antithrombin III or heparin cofactor.


CONCLUSIONS
The effect of Hcy in developing thrombosis may be associated with an inhibitory action on EC TM expression; which was independent of platelet aggregation or heparin cofactor activity.
Zhang
G
G
Second Affiliated Hospital, Hunan Medical University, Changsha 410011.
Zhao
H
H
Zhang
L
L
D000328:Adult; D000990:Antithrombin III / Q000378:metabolism; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology*; D005260:Female; D015844:Heparin Cofactor II / Q000378:metabolism*; D006710:Homocysteine / Q000494:pharmacology*; D006801:Humans; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects*; D011897:Random Allocation; D018180:Thrombomodulin / Q000096:biosynthesis*; D014471:Umbilical Veins / Q000166:cytology
D018180:Thrombomodulin; D006710:Homocysteine; D015844:Heparin Cofactor II; D000990:Antithrombin III