Influence of a plasma fraction of human blood, rich in high density lipoprotein, on in vitro formation of prostaglandin I 2 (PGI 2) and thromboxane A 2 (TXA 2)

Abstract

The influence of a plasma fraction of human blood, rich in high density lipoprotein (HDL), was investigated on the “in vitro” formation of PGI 2 and TXA 2. The addition of 1 mg HDL-cholesterol per ml incubation fluid stimulated significantly the biotransformation of prostaglandin H 2 into PGI 2 by the microsomal fraction of pig aorta. The TXB 2 formation capacity of whole clotted blood was inhibited by administration of HDL in a dose dependent manner. These results suggest that added HDL is able to enhance the ratio PGI 2:TXA 2. This did not depend on the preparation of HDL either by ultracentrifugation or by precipitation.