ISOPROSTANES, A NEW GROUP OF SUBSTANCES IN ANGIOLOGY - OF VALUE IN THE FUTURE

F-2-isoprostanes are prostaglandin F-2-like compounds being formed bq non-enzymatic peroxidation of arachidonic acid in vivo. They have a va riety of biological actions. The most important compound of this group is 8-epi-PGF(2 alpha) being capable to induce vasoconstriction in par ticular of lung- and renal vascular tissue. Isoprostanes are present i n esterified form; in free form they become available after hydrolysis by phospholipase A. An increase in isoprostanes is an important indic ator of oxidative stress in-vivo due to a variety of different noxi su ch as metal- or nonmetal ions or cigarette smoke. Isoprostanes show an activation of platelets; as a consequence of the interaction of 8-epi -PGF(2 alpha) with specific receptors platelet aggregation may be indu ced or may be enhanced together with other agonists. Due to these prel iminary results isoprostanes could become an interesting substance in angiology in the future for diagnosis of oxidative stress as well as i n the understanding of the pathogenesis of atherosclerosis.