title: Inhibition of anaphylactic histamine release from heterologously sensitized mast cells: differential effects of drugs which interfere with calcium influx.
abstract: Drug effects were studied on anaphylactic histamine release from rat mast cells sensitized in vitro with mouse IgE antibody. When histamine release was elicited by adding Ca-++ at various times after antigen-stimulation of sensitized cells in Ca++-free medium, the drugs to be tested were added shortly before each Ca++ addition. Quercetin was effective only when added before or immediately after antigen. Theophylline and disodium cromoglycate (DSCG) were active irrespective of the time interval between antigen and Ca++ addition. Verapamil was more effective when added before or simultaneously with antigen than when added later. When tested in the two-stage experiments, quercetin showed inhibition only in Stage 1 and verapamil was inhibitive primarily in Stage 1, while theophylline and DSCG wee only inhibitive in Stage 2. It seems that quercetin selectively and verapamil primarily act to block calcium-gate opening resulting from antigen-antibody interaction on the mast cell membrane, while theophylline and DSCG selectively inhibit the passage of calcium through open calcium channels.
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D004205:Cromolyn Sodium / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects*; D007114:Immunization; D007073:Immunoglobulin E / Q000276:immunology; D008297:Male; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011794:Quercetin / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013806:Theophylline / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
chemical_list: D000941:Antigens; D007073:Immunoglobulin E; D011794:Quercetin; D013806:Theophylline; D014700:Verapamil; D004205:Cromolyn Sodium; D002118:Calcium