FUNCTION OF TYPE-II PHOSPHOLIPASE A(2) IN DOPAMINE SECRETION BY RAT NEURONAL PC12 CELLS

When rat pheochromocytoma PC12 cells, which had differentiated into ne uron-like cells following culture with nerve growth factor, were activ ated with glutamate, approximately 40% of their type II phospholipase A(2) (PLA(2)) was released into the extracellular medium. Glutamate-st imulated secretion of dopamine from PC12 cells was suppressed by type II PLA(2) inhibitors. Exogenous type II PLA(2) added alone directly el icited release of dopamine from PC12 cells. Thus released type II PLA( 2) may be involved in the regulation of neurotransmitter exocytosis by PC12 cells.