Measurement of 8-iso-prostaglandin F2alpha in biological fluids as a measure of lipid peroxidation.

Several lines of evidence suggest that reactive oxygen species are implicated in human disease, including atherosclerosis, hypertension, and restenosis after angioplasty. The measurement of F(2)-isoprostanes (F(2)-iPs), formed nonenzymatically through free radical catalyzed attack on esterified arachidonate, provides a reliable tool for identifying populations with enhanced rates of lipid peroxidation. Among F(2)-isoPs, 8-iso-PGF(2alpha) (also referred to IPF(2alpha)-III) and IPF(2alpha)-VI are the most frequently measured in biological fluids. A variety of methods have been proposed to measure F(2)-isoprostanes in urine and plasma. Mass spectrometry has been developed for the measurement of both F(2)-isoprostanes but its use is limited as it is time-consuming and highly expensive. We have developed validated enzyme immunoassay (EIA) and radioimmunoassay (RIA) techniques using highly specific antisera for the measurement of 8-iso-PGF(2alpha). In contrast, the commercially available immunoassay kits are limited for their poor specificity. The measurement of specific isoprostanes, such as 8-iso-PGF(2alpha), in urine is a reliable, noninvasive index of lipid peroxidation that is of valuable help in dose-finding studies of natural and synthetic antioxidant agents.