Lipoxygenase activity in rat embryos and its potential for xenobiotic oxidation.

This paper reports dioxygenase activity in rat embryos and demonstrates for the first time the ability of rat embryo lipoxygenase (LO) to oxidize xenobiotics in vitro. Significant dioxygenase activity towards linoleic acid was found in cytosol isolated from rat embryos in different developmental stages on day 9 and 10 of gestation. All four xenobiotics tested were oxidized at significant rate by the LO in the presence of linoleic acid. Both dioxygenase activity and benzidine oxidation were inhibited by the known inhibitors of LO, i.e. nordihydroguaiaretic acid and eicosatriynoic acid. These findings suggest that LO may be an important pathway for xenobiotic metabolism in the rat embryo.