Phospholipase C-diglyceride lipase is a major pathway for arachidonic acid release in macrophages.

Macrophages are a rich source of arachidonic acid oxygenated metabolites and play a remarkable role in a number of physiopathological situations. The synthesis and secretion of arachidonic acid metabolites are triggered at the cytoplasmic membrane level. The present study was outlined to further investigate the cellular mechanisms controlling arachidonic acid release in macrophages. The results presented here strongly suggest that the amount of arachidonic acid released in macrophages in response to phagocytic challenge could be accounted for by a phospholipase C-diglyceride lipase system being unnecessary the presence of phospholipase A2 whose activity, on the other hand, was found vanishingly small in macrophage homogenates.