Effect of ionophore A23187 on the membrane permeability in mouse fibroblasts

Barun K. De, Ilan Friedberg

Research output: Contribution to journalArticlepeer-review

13 Scopus citations


Addition of the divalent cation ionophore A23187 to transformed mouse fibroblasts (3T6) resulted in an increase in the cell membrane permeability to normally impermeant solutes (e.g., nucleotides). The membrane permeability was assessed by following the efflux of prelabeled adenine nucleotides, the influx of p-nitrophenyl phosphate in cells attached to plastic dishes and reconstitution of intracellular protein synthesis in the presence of exogenously added normally impermeant factors required for macromolecular synthesis. The permeability change of 3T6 cells was found to be dependent on the specific presence of external calcium ion. The permeabilization was found to occur preferably in alkaline pH and specific to certain transformed cells. It is preceded by rapid efflux of K+, influx of Na+ and partial hydrolysis of cellular nucleotides in 3T6 cells. Similar ion fluxes were previously found tc precede cell permeabilization by electrogenic ionophores for monovalent ions and by exogenous ATP. Our data suggest that a calcium dependent process caused the K+ release and excess Na+ entry, causing dissipation of the membrane potential and subsequent formation of aqueous channels.

Original languageEnglish (US)
Pages (from-to)830-841
Number of pages12
JournalBiochemical and Biophysical Research Communications
Issue number3
StatePublished - Aug 15 1991

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Effect of ionophore A23187 on the membrane permeability in mouse fibroblasts'. Together they form a unique fingerprint.

Cite this