Acetylated low density lipoproteins promote the release and metabolism of arachidonic acid by murine macrophages.
It has been postulated that the ratio of prostacyclin/thromboxane A2 in the blood is an important marker for atherosclerosis. We studied the role of the Acetylated Low Density Lipoprotein (Acetyl-LDL) on the arachidonic acid metabolism in macrophages, the progenitor of the foam-cells in atheroma. When stimulated by Acetyl-LDL, macrophage released and metabolized arachidonic acid. This effect was time- and dose-dependent. Only 50% of the Acetyl-LDL-induced arachidonic acid released was metabolized while more than 90% of zymosan or A23187 induced arachidonic acid released was metabolized. Furthermore, when the macrophages were stimulated by Acetyl-LDL, a decrease of prostaglandin E2 and an increase of the levels of prostacyclin and thromboxane were noted. The implications of these observations in the pathogenesis of atherosclerosis are discussed.
Diez
E
E
Unidad de Lipidos and Atherosclerosis, Hospital Universitario de San Carlos, Universidad Complutense, Madrid, Spain.
Fernandez
B
B
Martin
C
C
Zamorano
P
P
Schuller
A
A
D000107:Acetylation; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D015815:Cell Adhesion Molecules; D066298:In Vitro Techniques; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D051379:Mice; D011973:Receptors, LDL / Q000502:physiology; D051116:Receptors, Scavenger; D013329:Structure-Activity Relationship; D015054:Zymosan / Q000494:pharmacology
D001095:Arachidonic Acids; D015815:Cell Adhesion Molecules; D008077:Lipoproteins, LDL; D011973:Receptors, LDL; D051116:Receptors, Scavenger; C032629:acetyl-LDL; D016718:Arachidonic Acid; D000001:Calcimycin; D015054:Zymosan