Cytokine-induced prostaglandin generation in rat mesangial cells has been suggested to be dependent on the expression of secretory phospholipase A 2 (sPLA 2 ). In the present study, we investigated the possible involvement of Ca 2 + -independent phospholipase A 2 (iPLA 2 ) in the generation. The results showed that bromoenol lactone, a relatively selective iPLA 2 inhibitor, significantly attenuated prostaglandin E 2 generation induced by interleukin-1β and dibutyryl cAMP in parallel with the inhibition of iPLA 2 activity. However, the inhibitor did not affect sPLA 2 release upon stimulation, activities of sPLA 2 or cytosolic phospholipase A 2 , or Ca 2 + ionophore-induced arachidonic acid liberation. These results suggest that prostaglandin E 2 generation upon stimulation may be partially mediated by iPLA 2 in addition to sPLA 2 .