title: Countergradients of nonchemotactic ligands for N-formylmethionylleucylphenylalanine (FMLP) receptors promote FMLP-induced chemotaxis.
abstract: Using the under-agarose chemotaxis assay, addition of compounds known to inhibit chemotaxis of leukocytes toward N-f-Met-Leu-Phe (FMLP) was made to the first well in a line of three wells, leukocytes to the middle well, and a slight excess of FMLP to the third well. The compounds included rifampin, fusidic acid, carbobenzoxy Phe-Met, phenylbutazone, sulfinpyrazone, sulfasalazine, and sulfapyridine. The countergradients created in this system markedly stimulated, not inhibited, locomotion toward FMLP. These results, based on functional responses, confirm data using radiolabeled FMLP and support the hypothesis that these compounds are nonchemotactic ligands for FMLP receptors.
authors.forename: G D
authors.initials: GD
authors.lastname: Gray
authors.forename: G M
authors.initials: GM
authors.lastname: Ohlmann
mesh_terms: D001667:Binding, Competitive; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D005672:Fusidic Acid / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000378:metabolism / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology; D010653:Phenylbutazone / Q000494:pharmacology; D044042:Receptors, Formyl Peptide; D011971:Receptors, Immunologic / Q000187:drug effects* / Q000378:metabolism; D012293:Rifampin / Q000494:pharmacology; D012460:Sulfasalazine / Q000494:pharmacology; D013442:Sulfinpyrazone / Q000494:pharmacology
chemical_list: D044042:Receptors, Formyl Peptide; D011971:Receptors, Immunologic; D012460:Sulfasalazine; D009240:N-Formylmethionine Leucyl-Phenylalanine; D005672:Fusidic Acid; D010653:Phenylbutazone; D013442:Sulfinpyrazone; D012293:Rifampin