1-Acyl-2-acetyl-sn-glycero-3-phosphocholine from stimulated human polymorphonuclear leukocytes

1-Acyl-2-acetyl-sn-glycero-3-phosphocholine (1-acyl-2-acetyl GPC) was found in the fraction of platelet-activating factor obtained from stimulated human polymorphonuclear leukocytes (PMN). The amount of 1-acyl-2-acetyl GPC obtained from 1 X 10(7) PMN stimulated with ionophore A23187 at 37 C for 15 min ranged from 8 to 56 pmol (32 +/- 10 pmol, mean +/- standard error; n = 4). The main species was 16:0 palmitoyl (17 +/- 5 pmol), followed by 18:0 stearoyl (8 +/- 3 pmol) and 18:1 oleoyl (7 +/- 3 pmol). Although the physiological significance is unknown, 1-acyl-2-acetyl GPC was always detected when 1-alkyl-2-acetyl GPC was detected.