Inhibition of prostaglandin biosynthesis by human low-density and high-density lipoproteins

The ability of human low-density lipoprotein (LDL) and high-density lipoprotein (HDL) to inhibit the biosynthesis of prostaglandin (PG) E2, F2 alpha prostacyclin from arachidonic acid by bull seminal vesicle (BSV) PG synthase was studied. Both LDL an HDL inhibited the PG synthase activity in BSV microsomes. The greatest inhibitory effect was observed against th biosynthesis of PGE2. These results show an higher to unrecognised property of human lipoproteins that may mediate some of the biological actions of these substances.