title: Neutrophils and mast cells: nedocromil sodium inhibits the generation of neutrophil-derived histamine-releasing activity (HRA-N).
abstract: The effect of nedocromil sodium on the generation of neutrophil-derived histamine-releasing activity (HRA-N) from human peripheral blood neutrophils and on the secretory effects of HRA-N and anti-IgE on rat basophil leukemia (RBL) cells was studied. Nedocromil sodium caused dose-related inhibition of HRA-N generation by human neutrophils (10(-7) to 10(-4) mol/L; inhibitory concentration of 50%, 1.5 x 10(-8) mol/L). In contrast, the presence of nedocromil sodium had no effect on HRA-N-mediated serotonin release from RBL cells. In five experiments, with one crude and four partially purified HRA-N preparations, serotonin release from RBL cells exposed to native HRA-N or HRA-N in the presence of nedocromil sodium (10(-4) mol/L) was 28% +/- 6% and 26% +/- 5%, respectively. Similar results were found with all concentrations of nedocromil sodium studied. Preincubation of RBL cells with nedocromil sodium (10(-4) mol/L) for 0 to 60 minutes also did not affect HRA-N-mediated serotonin release. Likewise, nedocromil sodium (10(-7) to 10(-4) mol/L) had no effect on anti-IgE-induced serotonin release from RBL cells. In 10 experiments, anti-IgE alone or in the presence of nedocromil sodium (10(-4) mol/L) induced 32% +/- 6% and 32% +/- 5% serotonin release, respectively. Preincubation of RBL cells with nedocromil sodium before anti-IgE exposure had no further effect. This is the first study of pharmacologic manipulation of the generation of a histamine-releasing factor. It is hypothesized that one possible mechanism whereby nedocromil sodium protects against asthma and allergic rhinitis is through inhibition of HRA-N generation.
authors.affiliation: National Institutes of Health, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892.
authors.forename: M V
authors.initials: MV
authors.lastname: White
authors.forename: R L
authors.initials: RL
authors.lastname: Phillips
authors.forename: M A
authors.initials: MA
authors.lastname: Kaliner
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D006636:Histamine Release / Q000187:drug effects*; D006801:Humans; D007073:Immunoglobulin E / Q000494:pharmacology; D008407:Mast Cells / Q000502:physiology*; D017835:Nedocromil; D009504:Neutrophils / Q000378:metabolism*; D015363:Quinolones / Q000494:pharmacology*; D012701:Serotonin / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D015363:Quinolones; D017835:Nedocromil; D012701:Serotonin; D007073:Immunoglobulin E