13-oxoODE is produced from 13-HODE by a NAD+-dependent dehydrogenase present in rat colonic mucosa. 13-OxoODE stimulates cell proliferation when instilled intrarectally in rats. 13-OxoODE has also been detected in preparations of rabbit reticulocyte plasma and mitochondrial membranes, mostly esterified to phospholipids. Production of 13-oxoODE is putatively linked to the maturation of reticulocytes to erythrocytes through the activity of 15-LO.