sphingomyelin [ 20 % molar ( 20 mol of sphingomyelin/80 mol of phosphatidylethanolamine ) ] activates phosphatidylethanolamine hydrolysis by intestinal mucosal phospholipase a2 , and then at higher concentrations ( 40 % molar ) substantially inhibits the activity .
C0020291
hydrolysis
C0031667
phospholipase a2