title: The inhibitory effect of polymyxin B on endotoxin-induced endogenous pyrogen production.
abstract: The effect of polymyxin B (PMB) on the endogenous pyrogen (EP)-induced property of lipopolysaccharide (LPS) in vitro was examined. PMB inhibited LPS when added to leukocyte suspension 5 min before or up to 30 min after the addition of LPS. The inhibitory effect was dose-related and appeared to be specific for LPS (including naturally occurring endotoxin). EP production in response to a different stimulus (staphylococci) was not prevented even when LPS-PMB complexes were presumably present. These data suggest that when experimental agents are found to stimulate the production of EP or lymphocyte activating factors (LAF, interleukin-1) in vitro, or when apparently spontaneous production of EP or LAF is seen, incubation with PMB may be a useful technique to exclude th effects of endotoxin contamination - especially when negative results have been obtained in the limulus gelation test.
mesh_terms: D000818:Animals; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D004731:Endotoxins / Q000494:pharmacology*; D005260:Female; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000187:drug effects / Q000276:immunology; D011112:Polymyxin B / Q000494:pharmacology*; D011113:Polymyxins / Q000494:pharmacology*; D011749:Pyrogens / Q000096:biosynthesis*; D011817:Rabbits; D013210:Staphylococcus / Q000276:immunology; D013997:Time Factors
chemical_list: D004731:Endotoxins; D008070:Lipopolysaccharides; D011113:Polymyxins; D011749:Pyrogens; D011112:Polymyxin B