| 1. |
- Alling, Christer, et al.
(författare)
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Evaluation of ethanol effects on PLC signal transduction pathways using cell lines of neuronal origin
- 1993
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Ingår i: Alcohol and alcoholism. Supplement. - 1358-6173. ; 2, s. 295-299
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Tidskriftsartikel (refereegranskat)abstract
- Human neuroblastoma cells SH-SY5Y and neuroblastoma-glioma cells NG 108-15 have been used as models for the elucidation of the effects of ethanol on receptor-mediated phospholipase C activity, c-fos mRNA expression and protein kinase C activity. Cells were exposed to ethanol (0-200 mM) for varying periods up to seven days. Agonist stimulated events were obtained in NG 108-15 cells with bradykinin and in SH-SY5Y cells with carbachol. Chronic ethanol exposure reduced the agonist-stimulated formation of inositol 1,4,5-trisphosphate in NG 108-15 cells and in SH-SY5Y cells. 100 mM ethanol for seven days increased the membrane bound and cytosolic forms of protein kinase C activity in SH-SY5Y cells. Carbachol (1 mM) induced a maximal c-fos mRNA response after 40 minutes in SH-SY5Y cells, an effect that could be mimicked through protein kinase C stimulation by phorbol esters.
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| 2. |
- Larsson, Christer, et al.
(författare)
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Mechanisms of muscarinic receptor-stimulated expression of c-fos in SH-SY5Y cells
- 1994
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Ingår i: European Journal of Pharmacology. - 1879-0712. ; 268:1, s. 19-28
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the signal cascade transducing carbachol stimulation into c-fos expression in SH-SY5Y neuroblastoma cells was investigated. 1,2-Diacylglycerol formation and c-fos expression were mediated via stimulation of muscarinic M1 receptors and the first 5 min of receptor stimulation were critical for these events. Application of 1,2-dioctanoylglycerol induced c-fos expression and this, as well as carbachol-stimulated c-fos expression, was inhibited by protein kinase C inhibitors. Increasing the intracellular Ca2+ concentration had only small effects on c-fos expression. There was a dependency on extracellular Ca2+ for maximal c-fos expression and 1,2-diacylglycerol formation. The carbachol-stimulated c-fos expression was potentiated by application of the protein phosphatase inhibitor okadaic acid. These results demonstrate the importance of 1,2-diacylglycerol formation for muscarinic receptor-stimulated, protein kinase C-mediated c-fos expression in the SH-SY5Y cells and that this cascade is counteracted by an okadaic acid-sensitive protein phosphatase.
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