Influence of platelet activating factor and a nonmetabolizable analogue on superoxide production by bone marrow derived macrophages.
Serum-free cultured macrophages could be stimulated for lucigenin-dependent chemiluminescence by platelet activating factor (PAF) and phorbol myristate acetate (PMA). Stimulation with PMA resulted in a desensitization against PAF, whereas prestimulation with PAF had no influence on a following response caused by PMA. The PAF analogue, 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (Et-18-OCH3), did not induce chemiluminescence by itself and desensitized the cells against PAF, like substimulating concentrations of PAF. PAF and PMA responsiveness was rapidly modulated in a similar manner during adherence of the cells to polystyrene tubes. At higher concentrations, Et-18-OCH3 as well as lysophosphatidylcholines potentiated PMA-induced chemiluminescence. The PAF analogue was most effective. Although PMA-induced chemiluminescence was stimulated at least 5-fold by Et-18-OCH3, this compound increased the PMA-induced activation of protein kinase C only 1.39-fold. The priming effect of Et-18-OCH3 was not reduced in the absence of extracellular Ca2+ and after cell membrane depolarisation.
Storch
J
J
Max-Planck-Institut für Immunbiologie, Freiburg, Federal Republic of Germany.
Ferber
E
E
Munder
P G
PG
D001854:Bone Marrow Cells; D006801:Humans; D008163:Luminescent Measurements; D008244:Lysophosphatidylcholines / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D010972:Platelet Activating Factor / Q000031:analogs & derivatives / Q000494:pharmacology*; D011493:Protein Kinase C / Q000032:analysis; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D008244:Lysophosphatidylcholines; D010972:Platelet Activating Factor; D013481:Superoxides; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate