Selectively hydrolyzes arachidonyl phospholipids in the sn-2 position releasing arachidonic acid. Together with its lysophospholipid activity, it is implicated in the initiation of the inflammatory response (By similarity). a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1-acyl-sn-glycero-3-phosphocholine + a fatty acid + H(+) a 1-acyl-sn-glycero-3-phosphocholine + H2O = a fatty acid + H(+) + sn-glycerol 3-phosphocholine Stimulated by agonists such as ATP, EGF, thrombin and bradykinin as well as by cytosolic Ca(2+). Translocates to membrane vesicles in a calcium-dependent fashion. The N-terminal C2 domain associates with lipid membranes upon calcium binding. It modulates enzyme activity by presenting the active site to its substrate in response to elevations of cytosolic Ca(2+) (By similarity).