Diphenyleneiodonium prevents reactive oxygen species generation, tyrosine phosphorylation, and histamine release in RBL-2H3 mast cells.
Mast cells play a central role in immediate allergic reactions mediated by immunoglobulin E. It has recently been reported that mast cells generate intracellular reactive oxygen species (ROS) in response to stimulation with divergent physiologically relevant stimulants. However, the physiological role of ROS is poorly understood. Here we demonstrate that mast cell model rat basophilic leukemia (RBL-2H3) cells generate ROS in response to antigen and the calcium-ionophore A23187 via activation of diphenyleneiodonuim (DPI)-sensitive enzyme and that blockade of ROS generation by DPI suppresses histamine release induced by either stimulant. Increased tyrosine phosphorylation of pp125(FAK) and a 77-kDa protein coprecipitating specifically with the kinase occurred in parallel with the secretion, and blockade of ROS generation by DPI also suppressed the tyrosine phosphorylation of both proteins. These findings suggest that ROS generated by a flavoenzyme-dependent mechanism may be involved in histamine release through the pp125(FAK) pathway.
Matsui
T
T
Department of Immunology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan.
Suzuki
Y
Y
Yamashita
K
K
Yoshimaru
T
T
Suzuki-Karasaki
M
M
Hayakawa
S
S
Yamaki
M
M
Shimizu
K
K
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D006632:Histamine / Q000378:metabolism*; D006636:Histamine Release; D008407:Mast Cells / Q000187:drug effects* / Q000378:metabolism; D008970:Molecular Weight; D009861:Onium Compounds / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D017455:Receptors, IgE / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism*
D004791:Enzyme Inhibitors; D009861:Onium Compounds; D017382:Reactive Oxygen Species; D017455:Receptors, IgE; D000001:Calcimycin; D014443:Tyrosine; C007517:diphenyleneiodonium; D006632:Histamine; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496052:Ptk2 protein, rat