Intracellular mechanisms of hydrogen peroxide-mediated neutrophil adherence to cultured human endothelial cells.
We examined which endothelial second messengers are involved in peroxide-mediated endothelial-neutrophil adhesion with respect to endothelial P-selectin expression and platelet-activating factor (PAF). Peroxide (0.5 mM)-mediated adhesion was blocked by a protein kinase C (PKC) inhibitor, Gö6976 (10 nM); an intracellular calcium chelator, TMB-8 (0.1 mM); and a protein kinase G (PKG) inhibitor, KT5823 (0.5 microM); but not by a tyrosine kinase inhibitor, genistein (1 microM), or a protein kinase A inhibitor, H-89 (0.1 microM). These data were consistent with the proadhesive effects of PMA (0.1 microM), a PKC activator; a calcium ionophore, A23187 (1 microM); and dibutyryl cGMP (0.5 and 1 mM); but not phenylarsine oxide (0.1 mM), a tyrosine phosphatase inhibitor, or dibutyryl cAMP (1 mM). Conversely, peroxide-mediated P-selectin expression was blocked by Gö6976 and KT5823, but not by TMB-8. These data are strengthened by the observation that PMA and dibutyryl cGMP, but not A23187, increased P-selectin expression. WEB 2086 (10 microM), a PAF-receptor antagonist, blocked peroxide-, PMA-, and A23187-mediated adhesion, but not peroxide-mediated P-selectin expression. PAF itself (10 nM) stimulated adhesion, but not P-selectin expression. These data indicate that PKC and PKG are involved in peroxide-mediated neutrophil adhesion via P-selectin mobilization and PAF synthesis; however, intracellular calcium appears to mediate adhesion only through PAF synthesis.
Okayama
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N
Department of Molecular and Cellular Physiology, Louisiana State University Medical Center, Shreveport, Louisiana, 71130-3932, USA.
Coe
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L
Oshima
T
T
Itoh
M
M
Alexander
J S
JS
D001381:Azepines / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D066298:In Vitro Techniques; D009504:Neutrophils / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D019007:P-Selectin / Q000378:metabolism; D010972:Platelet Activating Factor / Q000494:pharmacology; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D015290:Second Messenger Systems; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014230:Triazoles / Q000494:pharmacology
D001381:Azepines; D004791:Enzyme Inhibitors; D019007:P-Selectin; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D047428:Protein Kinase Inhibitors; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D014230:Triazoles; C039351:platelet activating factor receptor; C052518:WEB 2086; D000001:Calcimycin; D006861:Hydrogen Peroxide; D013755:Tetradecanoylphorbol Acetate