Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.

1. The effects of the protein kinase C inhibitor, Ro 31-8220, on the responses of cultured bovine adrenal chromaffin cells to nicotine, phorbol 12, 13-dibutyrate (PDBu) and K+ have been investigated. 2. Tyrosine hydroxylase activity was measured in situ in intact cells by measuring 14CO2 evolved fol...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Marley, P. D., Thomson, K. A.
Formato: Artículo
Lenguaje:English
Publicado: 1996
Materias:
Research Article
Acceso en línea:https://ncbi.nlm.nih.gov/pmc/articles/PMC1915873/
https://ncbi.nlm.nih.gov/pubmed/8886429
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id pubmed-1915873
record_format dspace
spelling pubmed-19158732008-01-10 Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220. Marley, P. D. Thomson, K. A. Br J Pharmacol Research Article 1. The effects of the protein kinase C inhibitor, Ro 31-8220, on the responses of cultured bovine adrenal chromaffin cells to nicotine, phorbol 12, 13-dibutyrate (PDBu) and K+ have been investigated. 2. Tyrosine hydroxylase activity was measured in situ in intact cells by measuring 14CO2 evolved following the hydroxylation and rapid decarboxylation of [14C]-tyrosine offered to the cells. Secretion of endogenous adrenaline and noradrenaline was measured by use of h.p.l.c. with electrochemical detection. Cyclic AMP levels were measured in cell extracts by RIA. 3. Ro 31-8220 produced a concentration-dependent inhibition of 300 nM PDBu-stimulated tyrosine hydroxylase activity with an IC50 of < 2 microM and complete inhibition at 10 microM. It had no effect on the responses to forskolin. 4. Ro 31-8220 produced a concentration-dependent inhibition of 5 microM nicotine-stimulated tyrosine hydroxylase activity, adrenaline and noradrenaline secretion and cellular cyclic AMP levels, with an IC50 of about 3 microM and complete inhibition by 10 microM. At concentrations up to 10 microM, Ro 31-8220 had little or no effect on the corresponding responses to 50 mm K+. 5. A structural analogue of Ro 31-8220, bisindolylmaleimide V, that lacks activity as a protein kinase C inhibitor, had no effect up to 10 microM on PDBu-stimulated tyrosine hydroxylase activity or on nicotine-stimulated cyclic AMP levels or noradrenaline secretion and only marginal inhibitory effects on nicotine-stimulated tyrosine hydroxylase activity and adrenaline secretion. 6. A structurally related protein kinase C inhibitor, bisindolylmaleimide I, inhibited PDBu-stimulated tyrosine hydroxylase activity with an IC50 of < 1 microM and complete inhibition by 3 microM, but had essentially no effect on nicotine stimulated tyrosine hydroxylase activity or catecholamine secretion. 7. The results suggest that Ro 31-8220 is not only a protein kinase C inhibitor but is also a potent inhibitor of nicotinic receptor responses in adrenal chromaffin cells by a mechanism unrelated to protein kinase C inhibition. The results are consistent with Ro 31-8220 being a nicotinic receptor antagonist. 1996-09 /pmc/articles/PMC1915873/ /pubmed/8886429 Text en
institution US National Library of Medicine
collection PubMed Central
language English
format Article
topic Research Article
spellingShingle Research Article
Marley, P. D.
Thomson, K. A.
Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
description 1. The effects of the protein kinase C inhibitor, Ro 31-8220, on the responses of cultured bovine adrenal chromaffin cells to nicotine, phorbol 12, 13-dibutyrate (PDBu) and K+ have been investigated. 2. Tyrosine hydroxylase activity was measured in situ in intact cells by measuring 14CO2 evolved following the hydroxylation and rapid decarboxylation of [14C]-tyrosine offered to the cells. Secretion of endogenous adrenaline and noradrenaline was measured by use of h.p.l.c. with electrochemical detection. Cyclic AMP levels were measured in cell extracts by RIA. 3. Ro 31-8220 produced a concentration-dependent inhibition of 300 nM PDBu-stimulated tyrosine hydroxylase activity with an IC50 of < 2 microM and complete inhibition at 10 microM. It had no effect on the responses to forskolin. 4. Ro 31-8220 produced a concentration-dependent inhibition of 5 microM nicotine-stimulated tyrosine hydroxylase activity, adrenaline and noradrenaline secretion and cellular cyclic AMP levels, with an IC50 of about 3 microM and complete inhibition by 10 microM. At concentrations up to 10 microM, Ro 31-8220 had little or no effect on the corresponding responses to 50 mm K+. 5. A structural analogue of Ro 31-8220, bisindolylmaleimide V, that lacks activity as a protein kinase C inhibitor, had no effect up to 10 microM on PDBu-stimulated tyrosine hydroxylase activity or on nicotine-stimulated cyclic AMP levels or noradrenaline secretion and only marginal inhibitory effects on nicotine-stimulated tyrosine hydroxylase activity and adrenaline secretion. 6. A structurally related protein kinase C inhibitor, bisindolylmaleimide I, inhibited PDBu-stimulated tyrosine hydroxylase activity with an IC50 of < 1 microM and complete inhibition by 3 microM, but had essentially no effect on nicotine stimulated tyrosine hydroxylase activity or catecholamine secretion. 7. The results suggest that Ro 31-8220 is not only a protein kinase C inhibitor but is also a potent inhibitor of nicotinic receptor responses in adrenal chromaffin cells by a mechanism unrelated to protein kinase C inhibition. The results are consistent with Ro 31-8220 being a nicotinic receptor antagonist.
author Marley, P. D.
Thomson, K. A.
author_facet Marley, P. D.
Thomson, K. A.
author_sort Marley, P. D.
title Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
title_short Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
title_full Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
title_fullStr Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
title_full_unstemmed Inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase C inhibitor, Ro 31-8220.
title_sort inhibition of nicotinic responses of bovine adrenal chromaffin cells by the protein kinase c inhibitor, ro 31-8220.
publishDate 1996
url https://ncbi.nlm.nih.gov/pmc/articles/PMC1915873/
https://ncbi.nlm.nih.gov/pubmed/8886429
_version_ 1760485709950484480

Ejemplares similares