Activation of neutrophils by diaclyglycerol hydroperoxides (A), diacylglycerol hydoxides (B), or diaclyglycerols (C). The maximum MCLA-dependent luminescence intensity was measured as the rate of superoxide anion formation from neutrophils (2.5 × 104 cells/ml). The concentration of each stimulator used here was 4 µM. One micromolar MCLA was used in this experiment. Results are expressed as means ± standard deviations (n = 5). Abbreviations used in the figures are as follows; PAG, 1-palmitoyl-2-arachidonoylglycerol; PLG, 1-palmitoyl-2-linoleoylglycerol; SAG, 1-stearoyl-2-arachidonoylglycerol; SLG, 1-stearoyl-2-linoleoylglycerol; 1,3-LLG, 1,3-dilinoleoylglycerol; OAG, 1-oleoyl-2-acetylglycerol; OOG, 1,2-dioleoylglycerol; -OOH, hydroperoxide; -OH, hydroxide.