Prostaglandin F_2α initiates polyphosphatidylinositol hydrolysis and membrane translocation of protein kinase C in swine ovarian cells

The biochemical mechanisms subserving the inhibitory actions of prostaglandin F_2α on ovarian cells are not known. Since the protein kinase C pathway is coupled to steroidogenesis in an inhibitory fashion in pig granulosa cells, we have tested the hypothesis that prostaglandin F_2α activates this phospholipid-dependent, calcium-stimulated effector pathway. Using monolayer cultures of swine granulosa cells, we now report that prostaglandin F_2α is capable of activating critical components of the protein kinase C pathway, including the production of water-soluble inositol phosphates, liberation of free arachidonic acid, release of endogenous diacylglycerol, and translocation of cytosolic protein kinase C to the phospholipid-enriched membrane microenvironment.