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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1993-4-16
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pubmed:abstractText |
Oligodendroglial cells express many specific proteins, such as myelin basic protein (MBP), which are physiologically phosphorylated by protein kinase C (PKC). Diacylglycerols are physiological activators of PKC and can be liberated from phospholipids by the direct receptor-mediated activation of phospholipase C (PL-C) or indirectly via the activation of phospholipase D (PL-D). In a well-characterized human oligodendroglioma (HOG) cell line, PL-C (measured by release of [3H]inositol phosphates) and PL-D (formation of [3H]myristoylated or palmitoylated phosphatidylethanol) were activated by both carbachol (blocked by pirenzepine, suggesting an M1 receptor) and histamine (H1 receptor) but not glutamate, bradykinin, or phenylephrine. PL-C stimulation by carbachol or histamine was completely inhibited by short-term treatment (< 30 min) with phorbol ester (TPA), a PKC activator. In contrast, PL-D activation by either carbachol or histamine was stimulated in additive fashion by TPA, suggesting at least two distinct mechanisms for PL-D activation. Down regulation of PKC by prolonged (24 hr) treatment with TPA reversed the inhibitory effects of TPA on PL-C and the stimulatory effects on PL-D. However, the PKC inhibitors H-7 and galactosylsphingosine did not inhibit the TPA-mediated stimulation of PLD while the less-specific PKC inhibitor, staurosporine, was only partially inhibitory. Preexposure of cells to carbachol, greatly reduced both PL-C and PL-D activation by carbachol, suggesting homologous desensitization. Time-course studies indicated that PL-D activation (10 sec or less) was at least as fast as PL-C activation, and the affinity of carbachol and histamine for the receptor coupled to either phospholipase (EC50 = 5-10 microM) was about the same.(ABSTRACT TRUNCATED AT 250 WORDS)
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Alkaloids,
http://linkedlifedata.com/resource/pubmed/chemical/Carbachol,
http://linkedlifedata.com/resource/pubmed/chemical/Histamine,
http://linkedlifedata.com/resource/pubmed/chemical/Inositol Phosphates,
http://linkedlifedata.com/resource/pubmed/chemical/Palmitates,
http://linkedlifedata.com/resource/pubmed/chemical/Phorbol Esters,
http://linkedlifedata.com/resource/pubmed/chemical/Phospholipase D,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C,
http://linkedlifedata.com/resource/pubmed/chemical/Staurosporine,
http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases
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pubmed:status |
MEDLINE
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pubmed:month |
Feb
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pubmed:issn |
0360-4012
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
15
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pubmed:volume |
34
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
324-30
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:8455209-Alkaloids,
pubmed-meshheading:8455209-Carbachol,
pubmed-meshheading:8455209-Chromatography, Thin Layer,
pubmed-meshheading:8455209-Down-Regulation,
pubmed-meshheading:8455209-Enzyme Activation,
pubmed-meshheading:8455209-Histamine,
pubmed-meshheading:8455209-Humans,
pubmed-meshheading:8455209-Hydrolysis,
pubmed-meshheading:8455209-Inositol Phosphates,
pubmed-meshheading:8455209-Nervous System Neoplasms,
pubmed-meshheading:8455209-Oligodendroglioma,
pubmed-meshheading:8455209-Palmitates,
pubmed-meshheading:8455209-Phorbol Esters,
pubmed-meshheading:8455209-Phospholipase D,
pubmed-meshheading:8455209-Protein Kinase C,
pubmed-meshheading:8455209-Staurosporine,
pubmed-meshheading:8455209-Tumor Cells, Cultured,
pubmed-meshheading:8455209-Type C Phospholipases
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pubmed:year |
1993
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pubmed:articleTitle |
Regulation of phospholipase D activity in a human oligodendroglioma cell line (HOG).
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pubmed:affiliation |
Department of Pediatrics, University of Chicago, IL 60637.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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