Analysis of Choline and Phosphorylcholine Content in Human Neutrophils Stimulated by f-Met-Leu-Phe and Phorbol Myristate Acetate

摘要: Abstract We analysed changes in choline (CHO) and phosphorylcholine (PCHO) content of stimulated human polymorphonuclear leukocytes (PMNs) by a chemiluminescence assay to further examine the relative contributions phospholipase D (PLD) PLC phosphatidylcholine (PC) breakdown. PLD activation was also measuring tritiated phosphatidic acid (PA) diglycerides (GDs) PMNs labelled with alkyl-lyso PC. Stimulation formyl-methionyl-leucyl-phenylalanine fMLP; 0.1 μM induced weak elevation mass (+25% basal level) that strongly potentiated primed cytochalasin B (+350% control value 657±53 pmol/10 7 cells). CHO production rapid transient, peaking within 1 min, ran parallel PA. Thereafter, amount PA declined (40% maximum 3 min), whereas elevated fMLP plateaued for at least 5 min. Phorbol myristate acetate (PMA) sustained formation as long 20 which correlated [ H]PA time- concentration-dependent manner. PCHO resting PMN (1560 ± 56 cells) not modified after stimulation or PMA 10 argues against breakdown PLC. For longer treatment (10–20 significant enhancement level, occurred concomitantly decrease suggesting kinase rather than may be activated. Unlike fMLP, fall between 15 min stimulation, pointing different regulatory mechanisms level. These data indicate DG from PC is mediated but show measurement reliable index activation.