title: Wortmannin inhibits store-mediated calcium entry and protein tyrosine phosphorylation in human platelets.
abstract: The effects of the WT on store-mediated Ca2+ entry and protein tyrosine phosphorylation were investigated in fura-2-loaded human platelets. Wortmannin (2 microM) attenuated the rise in [Ca2+]i caused by Ca2+ entry while having no effect on the mobilisation of Ca2+ from internal stores. It also reduced store-depletion-evoked protein tyrosine phosphorylation. These findings demonstrate that WT is an inhibitor of tyrosine phosphorylation and store-mediated calcium entry and provide further evidence for the involvement of a tyrosine phosphorylation step in the link between Ca2+ store depletion and Ca2+ influx in human platelets.
authors.affiliation: The Physiological Laboratory, University of Cambridge, UK.
authors.forename: S
authors.initials: S
authors.lastname: Jenner
authors.forename: R W
authors.initials: RW
authors.lastname: Farndale
authors.forename: S O
authors.initials: SO
authors.lastname: Sage
mesh_terms: D000730:Androstadienes / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D001798:Blood Proteins / Q000302:isolation & purification / Q000378:metabolism; D002118:Calcium / Q000097:blood*; D004533:Egtazic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005456:Fluorescent Dyes; D016257:Fura-2 / Q000031:analogs & derivatives; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010750:Phosphoproteins / Q000097:blood* / Q000302:isolation & purification; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000032:analysis; D013729:Terpenes / Q000494:pharmacology; D019284:Thapsigargin; D000077191:Wortmannin
chemical_list: D000730:Androstadienes; D001798:Blood Proteins; D004791:Enzyme Inhibitors; D005456:Fluorescent Dyes; D010726:Phosphodiesterase Inhibitors; D010750:Phosphoproteins; D013729:Terpenes; C049925:fura-2-am; D019000:Phosphotyrosine; D004533:Egtazic Acid; D019284:Thapsigargin; D002118:Calcium; D016257:Fura-2; D000077191:Wortmannin