8-iso-15-ketoProstaglandinF2α (8-iso-15-keto PGF2α) is a metabolite of the isoprostane 8-iso PGF2α in rabbits, monkeys, and humans. 8-isoprostane (8-iso PGF2α) is a prostaglandin-like product of non-specific lipid peroxidation. In both humans and monkeys, exogenously infused 8-iso PGF2α is converted primarily to metabolites having 2 or 4 carbon atoms removed from the top side chain by β-oxidation. A similar pattern is observed when tritiated 8-iso PGF2α is infused into rabbits. Early in the infusion (within 1-2 minutes) 8-iso -15-keto PGF2α was a major component of the metabolite profile, which was comprised mostly of unmetabolized 8-iso PGF2α. 8-iso -15-keto PGF2α is a vasoconstrictor when tested on the rat isolated thoracic aorta, acting via the TP (thromboxane) receptor.
8-isoProstaglandinF2β (8-iso PGF2β) is an isomer of PGF2α of non-enzymatic origin. It is one of 64 possible isomers of PGF2α which can be produced by free radical peroxidation of arachidonic acid. 8-iso PGF2β exhibits very weak contraction of human umbilical vein artery and does not promote aggregation of human whole blood. However, 8-iso PGF2β moderately contracts both the canine and porcine pulmonary vein, although the effect is much weaker than that exhibited by other isoprostanes such as 8-iso PGE1, 8-iso PGE2, or 8-iso PGF2α. 8-iso-15-keto PGF2β is a potential metabolite of 8-iso PGF2β via the 15-hydroxy PG dehydrogenase pathway. There are no published reports on the formation or biological activity of 8-iso-15-keto PGF2β.
8-iso-13,14-dihydro-15-ketoProstaglandinF2α (8-iso-13,14-dihydro-15-keto PGF2α) is a metabolite of the isoprostane, 8-isoprostane (8-iso PGF2α), in rabbits, monkeys and humans. 8-iso PGF2α is a PG-like product of non-specific lipid peroxidation. In both humans and monkeys, exogenously infused 8-isoprostane is converted primarily to metabolites having 2 or 4 carbon atoms removed from the top side chain by β-oxidation. A similar pattern is observed when tritiated 8-isoprostane is infused into rabbits. Early in the infusion (within 10 minutes) 8-iso-13,14-dihydro-15-keto PGF2α was a significant component of the metabolite profile, which was comprised mostly of dinor 8-isoprostane metabolites. 8-iso-13,14-dihydro-15-keto PGF2α weakly inhibits the U-46619 or collagen-induced aggregation of human platelets, although a number of the E-series isoprostanes are much more potent in this assay.