Differential effects of polychlorinated biphenyl congeners on phosphoinositide hydrolysis and protein kinase C translocation in rat cerebellar granule cells
| Autor: | Thomas R. Ward, G. J. Harry, Hugh A. Tilson, Theresa M. Freudenrich, Timothy J. Shafer, William R. Mundy, Prasada Rao S. Kodavanti |
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| Rok vydání: | 1994 |
| Předmět: |
Cerebellum
Glutamic Acid chemistry.chemical_element Calcium Phosphatidylinositols Phorbol Esters medicine Pi Animals Molecular Biology Cells Cultured Protein Kinase C Protein kinase C Voltage-dependent calcium channel Chemistry Hydrolysis General Neuroscience Glutamate receptor Glutamic acid Polychlorinated Biphenyls Rats medicine.anatomical_structure Biochemistry Biophysics Carbachol Neurology (clinical) Signal transduction Excitatory Amino Acid Antagonists Signal Transduction Developmental Biology |
| Zdroj: | Brain Research. 662:75-82 |
| ISSN: | 0006-8993 |
| Popis: | Previous reports from our laboratory have suggested that the neuroactivity of some polychlorinated biphenyl (PCB) congeners is associated with perturbations in cellular Ca(2+)-homeostasis. We have characterized further the neurochemical effects of PCBs on signal transduction in primary cultures of cerebellar granule cells. The present experiments found that neither 2,2'-dichlorobiphenyl (DCBP), an ortho-substituted congener, nor 3,3',4,4',5-pentachlorobiphenyl (PCBP), a non-ortho-substituted congener, affected basal phosphoinositide (PI) hydrolysis in cerebellar granule cells. However, at concentrations up to 50 microM, DCBP potentiated carbachol-stimulated PI hydrolysis, while decreasing it at 100 microM. PCBP, on the other hand, had no effect on carbachol-stimulated PI hydrolysis in concentrations up to 100 microM. [3H]Phorbol ester ([3H]PDBu) binding was used to determine protein kinase C (PKC) translocation. DCBP increased [3H]PDBu binding in a concentration-dependent manner and a twofold increase was observed at 100 microM in cerebellar granule cells. PCBP had no effect on [3H]PDBu binding at concentrations up to 100 microM. The effect of DCBP on [3H]PDBu binding was time-dependent and was also dependent on the presence of external Ca2+ in the medium. To test the hypothesis that DCBP increases [3H]PDBu binding by acting on receptor-activated calcium channels, the effects of DCBP were compared to those of L-glutamate. The effects of DCBP (50 microM) and glutamate (20 microM) were additive.(ABSTRACT TRUNCATED AT 250 WORDS) |
| Databáze: | OpenAIRE |
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