These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Platelet-activating factor activates mitogen-activated protein kinases through the activation of phosphatidylinositol 3-kinase and tyrosine kinase in human eosinophils.
    Author: Miike S, Kurasawa K, Saito Y, Iwamoto I.
    Journal: J Leukoc Biol; 2000 Jan; 67(1):117-26. PubMed ID: 10648006.
    Abstract:
    We determined whether platelet-activating factor (PAF) activates mitogen-activated protein (MAP) kinases in human eosinophils, and if so, which signaling pathways are utilized for the MAP kinase activation. PAF activated 42-and 44-kDa MAP kinases (ERK1/ERK2) in eosinophils, which became maximal at 1 min after stimulation. The PAF receptor antagonist E6123 and pertussis toxin inhibited the PAF-induced MAP kinase activation in eosinophils. The phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor wortmannin, tyrosine kinase inhibitors herbimycin A and genistein, and an intracellular Ca2+ chelator BAPTA/AM inhibited PAF-induced MAP kinase activation in eosinophils, whereas protein kinase C inhibitors staurosporine and calphostin C had no effect. Furthermore, wortmannin as well as herbimycin A and genistein, but not BAPTA/AM, prevented PAF-induced tyrosine phosphorylation of Shc adapter protein in eosinophils. Finally, the specific MEK inhibitor PD98059 inhibited PAF-induced chemotaxis in eosinophils. Taken together, these results indicate that PAF activates MAP kinases in eosinophils through the activation of PI 3-kinase and a tyrosine kinase and the increase in intracellular Ca2+ and that PAF-induced MAP kinase activation mediates chemotaxis in eosinophils.
    [Abstract] [Full Text] [Related] [New Search]