title: Granulocyte response to oxidized FMLP. Evidence for partial inactivation of FMLP.
abstract: We prepared FMoxLP by oxidation of FMLP and evaluated its ability to trigger a variety of granulocyte responses. FMoxLP was found to depolarize granulocyte membranes; increase granulocyte oxygen consumption, superoxide production, and hydrogen peroxide production; compete with FMLP for binding to granulocytes; and stimulate granulocyte chemotaxis. Against all of these granulocyte functions, FMoxLP was considerably less potent than the parent FMLP. When luminol-dependent-granulocyte chemiluminescence (CL) was studied, FMoxLP was observed to be a more potent stimulus of this response than FMLP. This increased CL activity of FMoxLP may be related to nonoxidative burst mechanisms. Our results indicate that FMoxLP retains a significant amount of the biological activity of FMLP (albeit in general less potent). The biological importance of the observed activities of FMoxLP must await further investigation.
mesh_terms: D000818:Animals; D002633:Chemotaxis / Q000187:drug effects; D006098:Granulocytes / Q000187:drug effects*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D008163:Luminescent Measurements; D008564:Membrane Potentials / Q000187:drug effects; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000031:analogs & derivatives* / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D013481:Superoxides / Q000096:biosynthesis
chemical_list: D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; C036773:N-formylmethionyl sulfoxide-leucyl-phenylalanine; D006861:Hydrogen Peroxide