title: Effects of ADP-ribosylation of GTP-binding protein by pertussis toxin on immunoglobulin E-dependent and -independent histamine release from mast cells and basophils.
abstract: Pretreatment of rat peritoneal mast cells, human basophils, bone marrow-derived mouse mast cells (BMMC) and mouse mast cell line PT-18 cells with 1 microgram/ml pertussis toxin (PT) failed to inhibit immunoglobulin E (IgE)-dependent histamine release from the cells. In BMMC and PT-18 cells, even 20-hr incubation of the cells with 1 microgram/ml PT, which ADP-ribosylates more than 97% of 41 kDa, alpha-subunit of Ni in the cells, failed to affect the IgE-dependent release of histamine or arachidonate. The results indicate that GTP-binding protein, Ni, is not involved in the transduction of triggering signals induced by cross-linking of IgE receptors. In contrast, pretreatment of rat mast cells with 1 ng/ml to 0.1 microgram/ml PT for 2 hr inhibited histamine release induced by compound 48/80 in a dose-dependent manner. A similar pretreatment with PT inhibited thrombin-induced histamine release from BMMC and N-formyl-L-methionyl-L-leucyl-L-phenylalanine-induced histamine release from human basophils in a similar dose-dependent fashion. However, even 20 hr of incubation of sensitized BMMC with 1 microgram/ml PT failed to inhibit either thrombin-induced or antigen-induced breakdown of phosphatidylinositides (PI), i.e., the formation of inositol triphosphate and diacylglycerol, Quin-2 signal, and the release of arachidonic acid. The results indicate that the inhibition of thrombin-induced histamine release by PT-treatment is not due to the inhibition of PI-turnover, and that Ni is not involved in thrombin-induced or antigen-induced (IgE-dependent) hydrolysis of phosphatidylinositides in mast cells.
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D000941:Antigens; D001491:Basophils / Q000502:physiology*; D001854:Bone Marrow Cells; D002462:Cell Membrane / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000502:physiology*; D006636:Histamine Release / Q000187:drug effects*; D006801:Humans; D007073:Immunoglobulin E / Q000502:physiology*; D008407:Mast Cells / Q000502:physiology*; D051379:Mice; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000378:metabolism; D051381:Rats; D013917:Thrombin / Q000378:metabolism; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
chemical_list: D000941:Antigens; D010716:Phosphatidylinositols; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D007073:Immunoglobulin E; D037342:Pertussis Toxin; D013917:Thrombin; D019204:GTP-Binding Proteins