PLASMA AND URINARY 8-ISO-PROSTANE AS AN INDICATOR OF LIPID-PEROXIDATION IN PREECLAMPSIA AND NORMAL-PREGNANCY

1. This study was designed to seek evidence for excessive lipid peroxi dation in pre-eclamptic women using 8-iso-prostane as a novel bioactiv e marker of lipid peroxidation irt vivo. Plasma free, total and urinar y 8-iso-prostane were measured in 20 women with proteinuric pre-eclamp sia, and compared with 18 age- and gestation-matched pregnant control subjects, before delivery and at 6 weeks postpartum. 2, Plasma free 8- iso-prostane was significantly elevated in the pre-eclamptic women com pared with control subjects before delivery, and fell to control level s post-partum. Conversely, levels in women with normal pregnancy rose post-partum 3. Total plasma 8-iso-prostane levels were not significant ly elevated in pre-eclamptic women compared with control subjects duri ng pregnancy, but fell significantly in the pre-eclamptic women postpa rtum, suggesting that they had relatively higher levels compared with their non-pregnant state. 4, Urinary 8-iso-prostane excretion was sign ificantly lower in the pre-eclamptic women compared with control subje cts during pregnancy, suggesting that renal clearance of 8-iso-prostan e is impaired in pre-eclampsia. 5. Increased levels of plasma free 8-i so-prostane in pre-eclampsia could be due to an increase in lipid pero xidation, an increase in phospholipase A(2) activity or a reduction in renal clearance of 8-iso-prostane, or a combination of all three, The potent direct and indirect vasoconstrictor actions of 8-iso-prostane may contribute to the pathogenesis of pre-eclampsia.