Alterations in calcium metabolism in murine macrophages by the benzene metabolite 1,4-benzoquinone.

Published

Journal Article

Exposure of murine peritoneal macrophages to very low concentrations of 1,4-benzoquinone (BQ) induced immediate increases in intracellular Ca2+ concentrations ([Ca2+]i). Increases in [Ca2+]i were induced by concentrations as low as 5 nM and the response was dose dependent and linear up to 1 microM. The sources of Ca2+ were from both internal inositol triphosphate (IP3)-sensitive and -insensitive sites and from the external medium. BQ did not induce IP3 formation and did not affect binding to its receptors. 1, 4-Hydroquinone had no effect on [Ca2+]i. Catechol did elicit some increases in [Ca2+]i, but did so only at much higher concentrations (5 microM). The action of BQ was almost identical to that of the established Ca2+-ATPase inhibitor thapsigargin except that there were some intracellular stores of Ca2+ released by thapsigargin that were not released by BQ. BQ also was mitogenic for macrophages in conjunction with phorbol myristate acetate. These data suggest that BQ raises [Ca2+]i by inhibition of Ca2+-ATPases, is a comitogen, and does so at concentrations that could be achieved in vivo in the general urban population.

Full Text

Duke Authors

Cited Authors

  • Misra, UK; Gawdi, G; Lewis, JG; Pizzo, SV

Published Date

  • July 1998

Published In

Volume / Issue

  • 151 / 1

Start / End Page

  • 1 - 8

PubMed ID

  • 9705881

Pubmed Central ID

  • 9705881

International Standard Serial Number (ISSN)

  • 0041-008X

Digital Object Identifier (DOI)

  • 10.1006/taap.1998.8415

Language

  • eng

Conference Location

  • United States