Assay of Cellular Diacylglycerol and Monoacylglycerol Lipases

Arachidonic acid has been implicated as a second messenger in numerous systems, and many agonists stimulate the intracellular accumulation of arachidonic acid (1,2). Arachidonic acid may be generated by phospholipase A2 hydrolysis of phospholipids, or by hydrolysis of diacylglycerol through the sequential action of diacylglycerol lipase and monoacylglycerol lipase (3–6). These activities can be easily measured using sensitive radiometric assays as described herein.