Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-8-4
pubmed:abstractText
Unlike resident peritoneal macrophages (RPM) or tumor necrosis factor alpha (TNF alpha)-primed bone marrow-derived macrophages (BMM), unprimed BMM do not generate superoxide in response to the protein kinase C (PKC) activator, phorbol myristate acetate (PMA). However, these cells do contain significant levels of PKC activity. In contrast to PMA, zymosan induces the generation of superoxide in unprimed BMM, as well as in TNF alpha-primed BMM and RPM. Staurosporine, a potent PKC inhibitor, failed to affect the zymosan-induced production of superoxide by unprimed and TNF alpha-primed BMM and RPM, in spite of substantial inhibition of PMA-induced superoxide production by the primed BMM and RPM. However, when PKC was depleted from unprimed BMM by prolonged (24 h) treatment with phorbol dibutyrate (PdBt) (10(-7) M) the ability of zymosan to induce the production of superoxide was greatly diminished. Such a result could be interpreted as suggesting a role for PKC in the zymosan-induced response, a conclusion which contrasts with the inhibitor data. However, PKC depletion, in this case, is achieved via the PdBt-induced activation of PKC. It is thus possible that it is the initial activation of PKC, rather than its depletion, that suppresses superoxide production. Consistent with this interpretation, the co-stimulation of unprimed BMM with both zymosan and PMA resulted in a reduced superoxide release compared to zymosan alone. The activation of PKC therefore appears to have a suppressive effect on the generation of superoxide by unprimed cells. We thus conclude that PKC is not required for zymosan-induced superoxide production by either primed or unprimed macrophages and suggest that PKC may be involved in regulatory mechanisms restricting superoxide production by macrophages. However, since PMA alone can initiate the release of superoxide from primed BMM and RPM, it would appear that PKC can mediate both stimulatory and suppressive signals for macrophage superoxide production.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Alkaloids, http://linkedlifedata.com/resource/pubmed/chemical/Cytokines, http://linkedlifedata.com/resource/pubmed/chemical/Endotoxins, http://linkedlifedata.com/resource/pubmed/chemical/Granulocyte-Macrophage..., http://linkedlifedata.com/resource/pubmed/chemical/Inositol Phosphates, http://linkedlifedata.com/resource/pubmed/chemical/Iodine Radioisotopes, http://linkedlifedata.com/resource/pubmed/chemical/Phorbol 12,13-Dibutyrate, http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C, http://linkedlifedata.com/resource/pubmed/chemical/Staurosporine, http://linkedlifedata.com/resource/pubmed/chemical/Superoxides, http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Necrosis Factor-alpha, http://linkedlifedata.com/resource/pubmed/chemical/Zymosan
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9541
pubmed:author
pubmed:issnType
Print
pubmed:volume
152
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
64-70
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:1320039-Alkaloids, pubmed-meshheading:1320039-Animals, pubmed-meshheading:1320039-Biological Transport, pubmed-meshheading:1320039-Bone Marrow Cells, pubmed-meshheading:1320039-Cells, Cultured, pubmed-meshheading:1320039-Cytokines, pubmed-meshheading:1320039-Dose-Response Relationship, Drug, pubmed-meshheading:1320039-Endotoxins, pubmed-meshheading:1320039-Granulocyte-Macrophage Colony-Stimulating Factor, pubmed-meshheading:1320039-Inositol Phosphates, pubmed-meshheading:1320039-Iodine Radioisotopes, pubmed-meshheading:1320039-Macrophages, pubmed-meshheading:1320039-Mice, pubmed-meshheading:1320039-Mice, Inbred CBA, pubmed-meshheading:1320039-Phorbol 12,13-Dibutyrate, pubmed-meshheading:1320039-Protein Kinase C, pubmed-meshheading:1320039-Staurosporine, pubmed-meshheading:1320039-Superoxides, pubmed-meshheading:1320039-Tetradecanoylphorbol Acetate, pubmed-meshheading:1320039-Time Factors, pubmed-meshheading:1320039-Tumor Necrosis Factor-alpha, pubmed-meshheading:1320039-Zymosan
pubmed:year
1992
pubmed:articleTitle
Protein kinase C has both stimulatory and suppressive effects on macrophage superoxide production.
pubmed:affiliation
University of Melbourne, Department of Medicine, Royal Melbourne Hospital, Parkville, Victoria, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't