Comparative effects of technical toxaphene, 2,5-dichloro-3-biphenylol and octabromodiphenylether on cell viability, [Ca2+]i levels and membrane fluidity in mouse thymocytes

SANDAL S., Yilmaz B., Chen C., Carpenter D. O.

Toxicology Letters, vol.151, no.3, pp.417-428, 2004 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 151 Issue: 3
  • Publication Date: 2004
  • Doi Number: 10.1016/j.toxlet.2004.03.006
  • Journal Name: Toxicology Letters
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.417-428
  • Keywords: Flow cytometry, Organohalogenated compounds, PCBs
  • Dokuz Eylül University Affiliated: No

Abstract

Flow cytometric studies of mouse thymocytes show that technical toxaphene (10-20 ppm) and 2,5-dichloro-3-biphenylol (PCB 9-OH) (5-10 ppm) kill cells and cause an increase in intracellular calcium concentration, [Ca2+] i, whereas commercial octabromodiphenylether (OBDE) has no effect. The cell death is not a result of the rise of [Ca2+]i, since the divalent cation ionophore, ionomycin, causes a large elevation in [Ca2+]i without cell death. We have studied effects of these compounds on membrane fluorescence polarization, a measure of membrane fluidity, using 1,6-diphenyl-1,3,5-hexatriene (DPH). We find that toxaphene causes a decrease in membrane fluidity in the concentration range associated with cell death, whereas PCB 9-OH causes an increase in fluidity and OBDE has no effect. These observations suggest that alterations of membrane fluidity of thymocytes, whether it be an increase or decrease, can cause cytotoxicity. © 2004 Elsevier Ireland Ltd. All rights reserved.