Reconstituted high density lipoprotein (rHDL) modulates platelet activity in vitro and ex vivo.
A reconstituted high density lipoprotein (rHDL) prepared for clinical use was tested for its influence on platelet activity modulated by various stimuli. In a first series of in vitro experiments, rHDL was added to blood in a concentration series, and platelet rich plasma (PRP) was isolated. Platelets were stimulated with arachidonic acid, collagen, epinephrine or ADP, and platelet aggregation was assessed. rHDL mediated a dose dependent inhibition of the platelet activity. With purified platelets rHDL inhibited the release reaction induced by collagen, but not by thrombin, as measured by CD62P (P-Selectin) expression on the plasma membrane. Ex vivo experiments were performed with PRP from volunteers, previously infused with 25 mg rHDL/kg body weight and 40 mg rHDL/kg body weight, respectively. Platelet activity in PRP was assessed before, and up to 30 h after the end of the rHDL infusion. A transient inhibition of the platelet aggregation induced by arachidonic acid and collagen was observed which was more pronounced in the group receiving 40 mg rHDL/kg body weight. In both groups of experiments, in vitro and ex vivo, the inhibition of the platelet activity was also dependent on the stimulus used.
ZLB Central Laboratory, Blood Transfusion Service SRC, Bern, Switzerland.
P G
PG
Lerch
M O
MO
Spycher
J E
JE
Doran
D006801:Humans; D007262:Infusions, Intravenous; D008055:Lipids / Q000097:blood; D008075:Lipoproteins, HDL / Q000494:pharmacology*; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D012016:Reference Values
D008055:Lipids; D008075:Lipoproteins, HDL; D010975:Platelet Aggregation Inhibitors