title: Regulation of human neutrophil degranulation by LY-83583 and L-arginine: role of cGMP-dependent protein kinase.
abstract: The effects of guanosine 3',5'-cyclic monophosphate (cGMP) on the secretory response of activated human neutrophils were investigated using LY-83583, an inhibitor of soluble guanylate cyclase, and L-arginine, the precursor of nitric oxide formation. A 30% release of myeloperoxidase (MPO) and lactoferrin (LF) from the primary and specific granules, respectively, was detected by enzyme-linked immunosorbent assay in adhered neutrophils stimulated with 0.1 microM N-formyl-methionyl-leucyl-phenylalanine (FMLP) or 20 microM A-23187. LY-83583 (100 microM) inhibited the release of both LF and MPO after stimulation with FMLP or A-23187. Conversely, preincubation of neutrophils with 0.5 mM L-arginine augmented the release of LF and MPO in FMLP- and A-23187-stimulated cells. Concurrent with the increase in the degranulation response was an elevation of cGMP levels in L-arginine-treated cells, while stimulated cGMP levels were reduced in LY-83583-treated cells. Furthermore, cGMP-dependent protein kinase (G-kinase) activity was reduced in LY-83583-treated cells, as determined by the delay in G-kinase translocation to intermediate filaments and the inhibition of vimentin phosphorylation. Degranulation, elevation of cGMP levels, and targeting of G-kinase were also dependent on the concentration of A-23187 or FMLP. These data suggest that activators of neutrophil degranulation mediate this response through a cGMP-dependent protein kinase mechanism.
authors.affiliation: Department of Pathology, University of North Carolina, Chapel Hill 27599-7525.
authors.forename: T A
authors.initials: TA
authors.lastname: Wyatt
authors.forename: T M
authors.initials: TM
authors.lastname: Lincoln
authors.forename: K B
authors.initials: KB
authors.lastname: Pryzwansky
mesh_terms: D000634:Aminoquinolines / Q000494:pharmacology*; D001120:Arginine / Q000494:pharmacology*; D015550:Cell Degranulation / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D006801:Humans; D008247:Lysosomes / Q000201:enzymology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000502:physiology*; D014018:Tissue Distribution; D014746:Vimentin / Q000378:metabolism
chemical_list: D000634:Aminoquinolines; D014746:Vimentin; C041715:6-anilino-5,8-quinolinedione; D001120:Arginine; D011494:Protein Kinases