Lipophilic Cations as Membrane Probes in Cultured Renal (LLC-PK1) and Muscle Cells (L6)
Tetraphenylphosphonium (TPP) and triphenylmethylphosphonium (TPMP) are lipophilic cations which have been used to measure transmembrane potentials in vesicles, mitochondria, and plant and animal cells (Cafimo and Hubbell, 1978; Ritchie, 1984). The use of TPP and TPMP to estimate electrical potentials in animal cells has many sources of error. There is, however, a qualitative proportionality between their uptake and the transmembrane potential difference which can provide useful information about the biological activity of chemicals. Lipophilic cations have also been used as probes of charge alterations in both lipid and protein domains of biomembranes (Levitsky et al., 1986; Cafiso, 1984). The relationship between charge alterations on, or within, biomembranes and the manifestations of toxicity in animals is not well established. None-theless, in vitro studies indicate that such alterations can have profound effects on transport systems and receptors associated with cell membranes (Levitsby et al., 1986; Cafiso, 1984).
KeywordsCyclopiazonic Acid Lipophilic Cation Potential Partition Efflux Kinetic Transmembrane Potential Difference
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
Cafiso, D.S., 1984, Paramagnetic hydrophobic ions as probes for electrically active conformational transitions in ion channels, Biophys. J.
Cafiso, D.S. and Hubbell, W.L., 1978, Estimation of transmembrane potentials from phase equilibria of hydrophobic paramagnetic ions, Biochemistry
, 17:187.PubMedCrossRefGoogle Scholar
Levitsky, D.O., Loginov, V.A. and Lebedev, A.V., 1986, Charge changes in sarcoplasmic reticulum and Ca2+
-ATPase induced by calcium binding and release: A study using lipophilic ions, Membr. Biochem.
, 6:291.PubMedCrossRefGoogle Scholar
Riley, R.T., Norred, W.P., Dorner, J.W. and Cole, R.J.: 1985, Increased accumulation of the lipophilic cation tetraphenylphosphonium by cyclopiazonic acid-treated renal epithelial cells, Toxicol. Environ. Health
, 15:779.CrossRefGoogle Scholar
Riley, R.T., Showker, J.L., Cole, R.J. and Dorner, J., 1986; The mechanism by which cyclopiazonic acid potentiates accumulation of tetraphenyl-phosphonium in cultured renal epithelial cells, J. Biochem. Toxicol.
, 1:13.PubMedCrossRefGoogle Scholar
Ritchie, R.J., 1984, A critical assessment of the use of lipophilic cations as membrane potential probes, Prog. Biophys. Molec. Biol.
, 13:1.CrossRefGoogle Scholar
© Springer Science+Business Media New York 1989