[The effect of platelet-activating factor and its antagonist--BN 52021--on immune reactions in vivo in mice and in vitro].
The effect produced by the injection of platelet activation factor (PAF) and its antagonist BN 52021 on the intensity of humoral immune response in (CBA x C57BL)F1 mice was studied. PAF was found to stimulate the formation of antibodies to sheep red blood cells. In addition PAF stimulated the phagocytic activity of mouse peritoneal macrophages. The stimulation of immune response under the action of PAF may be attributed to an increase in the phagocytic activity of macrophages. The stimulating effect of PAF on immune response in vivo was abolished by the injection of BN 52021, the antagonist of PAF. At the same time the dose-dependent decrease of immune response was observed after the injection of BN 52021. Indomethacin, an inhibitor of prostaglandin synthesis, when administered to mice treated with BN 52021, abolished the BN 52021-induced suppression of humoral immune response. Mouse peritoneal macrophages, treated in vitro with BN 52021, were found to produce significantly more prostaglandin E than control macrophages. Thus, BN 52021 induced the suppression of humoral immune response in vivo; this suppression was probably due to the action of prostaglandin E2, a messenger of the second order. Besides, the PAF antagonist BN 52021 significantly decreased leukotriene B4 production by macrophages in vitro. BN 52021 may be supposed to switch over the synthesis and/or secretion of arachidonic acid from the lipoxygenase pathway to the cycloxygenase one.
Poveshchenko
A F
AF
Institute of Clinical Immunology, Novosibirsk, Russia.
Kozlov
V A
VA
D000818:Animals; D000921:Antibody-Producing Cells / Q000187:drug effects / Q000276:immunology; D000937:Antigen-Antibody Reactions / Q000187:drug effects* / Q000276:immunology; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004224:Diterpenes; D004306:Dose-Response Relationship, Immunologic; D046934:Ginkgolides; D007114:Immunization / Q000379:methods; D007213:Indomethacin / Q000494:pharmacology; D007783:Lactones / Q000494:pharmacology*; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors* / Q000187:drug effects / Q000494:pharmacology*; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors / Q000187:drug effects; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D013154:Spleen / Q000187:drug effects / Q000276:immunology; D013997:Time Factors
D016861:Cyclooxygenase Inhibitors; D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor; C045856:ginkgolide B; D007213:Indomethacin
Vliianie faktora, aktiviruiushchego trombotsity, i ego antagonist--BN 52021 na immunnye reaktsii in vivo u mysheĭ i in vitro.