title: Antigen-induced phospholipase D activation in rat mast cells is independent of protein kinase C.
abstract: In the present study, we investigated the involvement of protein kinase C (PKC) in antigen (Ag, DNP-Ascaris suum)-induced phospholipase D (PLD) activation of rat peritoneal mast cells. Phorbor myristate acetate (PMA) as well as Ag activated PLD as inferred by phosphatidylethanol (PEt) production. PKC inhibitors, staurosporine and H-7, however, failed to suppress PMA-stimulated PLD activation, suggesting that PLD activation by PMA is independent of PKC. By contrast, Ag-stimulated PLD activity was significantly reduced by staurosporine and slightly by H-7. Surprisingly, the inhibitors inhibited Ag-stimulated phospholipase C (PLC), correlated to the inhibition of PLD. These observations lead us to conclude that in Ag-stimulated mast cells 1,2-diacylglycerol (DG) formed by PLC directly or indirectly stimulates PLD, independently of PKC.
authors.affiliation: Department of Biochemistry, Gifu University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamada
authors.forename: Y
authors.initials: Y
authors.lastname: Kanaho
authors.forename: K
authors.initials: K
authors.lastname: Miura
authors.forename: Y
authors.initials: Y
authors.lastname: Nozawa
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D000947:Antigens, Helminth; D001200:Ascaris / Q000276:immunology; D004789:Enzyme Activation; D004790:Enzyme Induction; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007546:Isoquinolines / Q000494:pharmacology*; D007700:Kinetics; D008407:Mast Cells / Q000201:enzymology* / Q000378:metabolism; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D010739:Phospholipase D / Q000096:biosynthesis / Q000378:metabolism*; D010879:Piperazines / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D011919:Rats, Inbred Strains; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000470:Alkaloids; D000947:Antigens, Helminth; D007546:Isoquinolines; D009227:Myristic Acids; D010879:Piperazines; D019814:Myristic Acid; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D015544:Inositol 1,4,5-Trisphosphate; D011493:Protein Kinase C; D010739:Phospholipase D; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate