Arachidonate lipoxygenase metabolite formation in gestational tissues

Products of arachidonic acid metabolism via the lipoxygenase pathways have a potential role in the onset of human labor. We have determined whether activation of protein kinase C can modulate the rate of biosynthesis within the uterus of five important arachidonate lipoxygenase metabolites, i.e., leukotriene B4 (LTB4), LTC4, 5-hydroxyeicosatetraenoic acid (5-HETE), 12-HETE and 15-HETE. Amnion, chorion laeve and decidual cells were isolated, grown to confluence and incubated with phorbol 12-myristate 13-acetate (PMA). PMA caused concentration-related stimulation of 5-HETE, 12-HETE and 15-HETE (but not LTB4) production; there were some stimulatory actions on decidual and amnion (but not chorion) LTC4 production. We postulate that activation of protein kinase C can result in enhanced production of arachidonate lipoxygenase metabolites that may have actions on the parturient process.