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The Journal of Membrane Biology

, Volume 117, Issue 3, pp 285–298 | Cite as

Electrophysiology of cultured human lens epithelial cells

  • Kim Cooper
  • Peter Gates
  • James L. Rae
  • Jerry Dewey
Articles

Summary

The lens epithelial K+ conductance plays a key role in maintaining the lens ionic steady state. The specific channels responsible for this conductance are unknown. We used cultured lens epithelia and patch-clamp technology to address this problem. Human lens epithelial explants were cultured and after 1–4 passages were dissociated and used in this study. The cells from which we measured had a mean diameter of 31±1 μm (sem,n=26). The resting voltage was −19±4 mV (sem,n=10) and the input resistance was 2.5±0.5 GΩ (sem,n=17) at −60 mV. Two currents were prominent in whole-cell recordings. An outwardly rectifying current was seen in nearly every cell. The magnitude of this current was a function of K+ concentration and was blocked by 3mm tetraethylammonium. The instantaneous current-voltage relationship was linear in symmetric K+, implying that the outward rectificiation was due to gating. The current showed complex activation and inactivation kinetics. The second current seen was a transient inward current. This current had kinetics very similar to the traditional Na+ current of excitable cells and was blocked by 0.1 μm tetrodotoxin. In single-channel recordings, a 150-pS K+ channel and a 35-pS nonselective cation channel were seen but neither account for the macroscopic currents measured.

Key Words

lens epithelium whole-cell recording cell culture K+ current Na+ current ion channel 

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References

  1. Bezanilla, F. 1985. A high capacity data recording device based on a digital audio processor and a video cassette recorder.Biophys. J. 47:437–441PubMedGoogle Scholar
  2. Blatz, A.L., Magleby, K.L. 1987. Calcium-activated potassium channels.Trends Neurosci. 10:463–467Google Scholar
  3. Brown, N.A.P., Bron, A.J. 1987. An estimate of the human lens epithelial cell size in vivo.Exp. Eye Res. 44:899–906PubMedGoogle Scholar
  4. Christensen, O. 1987. Mediation of cell volume regulation by Ca2+ influx through stretch-activated channels.Nature (London) 330:66–68Google Scholar
  5. Cooper, K., Rae, J.L., Gates, P. 1989. Membrane and junctional properties of dissociated frog lens epithelial cells.J. Membrane Biol. 111:215–227Google Scholar
  6. DeCoursey, T.E., Jacobs, E.R., Silver, M.R. 1988. Potassium currents in rat type II alveolar epithelial cells.J. Physiol. (London) 395:487–505Google Scholar
  7. Ermishkin, L.N., Kasumov, Kh.M., Potzeluyev, V.M. 1976. Single ionic channels induced in lipid bilayers by polyene antibiotics amphotericin B and nystatine.Nature (London) 262:698–699Google Scholar
  8. Fain, G.L., Farahbakhsh, N.A. 1989. Voltage-activated currents recorded from rabbit pigmented ciliary body epithelial cells.J. Physiol. (London) 417:83–103Google Scholar
  9. Freshney, R.I. 1987. Culture of Animal Cells: A Manual of Basic Technique. Alan R. Liss, New YorkGoogle Scholar
  10. Gogelein, H. 1988. Chloride channels in epithelia.Biochim. Biophys. Acta 947:521–547PubMedGoogle Scholar
  11. Hamada, Y., Okada, T.S. 1978. In vitro differentiation of cells of the lens epithelium of human fetus.Exp. Eye Res. 26:91–97PubMedGoogle Scholar
  12. Hoffmann, E.K., Simonsen, L.O. 1989. Membrane mechanisms in volume and pH regulation in vertebrate cells.Physiol. Rev. 69:315–382PubMedGoogle Scholar
  13. Horn, R., Marty, A. 1988. Muscarinic activation of ionic currents measured by a new whole-cell recording method.J. Gen. Physiol. 92:145–159PubMedGoogle Scholar
  14. Hunter, M., Oberleithner, H., Henderson, R.M., Giebisch, G. 1988. Whole-cell potassium currents in single early distal tubule cells.Am. J. Physiol. 255:F699-F703PubMedGoogle Scholar
  15. Jacob, T.J.C. 1988. Fresh and cultured human lens epithelial cells: An electrophysiological study of cell coupling and membrane properties.Exp. Eye Res. 47:489–506PubMedGoogle Scholar
  16. Lindau, M., Fernandez, J.M. 1986. IgE-mediated degranulation of mast cells does not require opening of ion channels.Nature (London) 319:150–153Google Scholar
  17. Marty, A., Neher, E. 1983. Tight-seal whole-cell recording.In: Single-Channel Recording. B. Sakmann and E. Neher, editors. pp. 107–122. Plenum, New YorkGoogle Scholar
  18. McCann, J.D., Welsh, M.J. 1990. Regulation of Cl and K+ channels in airway epithelium.Annu. Rev. Physiol. 52:115–135PubMedGoogle Scholar
  19. Nagineni, C.N., Bhat, S.P. 1989. Human fetal lens epithelial cells in culture: An in vitro model for the study of crystallin expression and lens differentiation.Curr. Eye Res. 8:285–291PubMedGoogle Scholar
  20. Palmer, L.G., Frindt, G. 1986. Epithelial sodium channels: Characterization by using the patch-clamp technique.Fed. Proc. 45:2708–2712PubMedGoogle Scholar
  21. Partridge, L.D., Swandulla, D. 1988. Calcium-activated non-specific cation channels.Trends Neurosci.11:69–72PubMedGoogle Scholar
  22. Patmore, L., Maraini, G. 1986. A comparison of membrane potentials, sodium and calcium levels in normal and cataractous human lenses.Exp. Eye Res. 43:1127–1130PubMedGoogle Scholar
  23. Petersen, O.H. 1987. Electrophysiology of exocrine gland cells.In: Physiology of the Gastrointestinal Tract. L.R. Johnson, editor, pp. 745–771. Raven, New YorkGoogle Scholar
  24. Petersen, O.H. 1989. Patch-clamp experiments in epithelia: Activation by hormones or neurotransmitters.Methods Enzymol.171:663–678PubMedGoogle Scholar
  25. Press, B.P., Flannery, W.H., Teukolsky, S.A., Vetterling, W.T. 1986. Numerical Recipes: The Art of Scientific Computing. Cambridge University Press, CambridgeGoogle Scholar
  26. Rae, J.L. 1984. The patch voltage clamp: Its application to lens research.Lens Res.2:61–87Google Scholar
  27. Rae, J.L., Cooper, K. 1990. New techniques for the study of lens electrophysiology.Exp. Eye Res. (in press) Google Scholar
  28. Rae, J.L., Dewey, J., Cooper, K. 1989. Properties of single potassium-selective ionic channels from the apical membrane of rabbit corneal endothelium.Exp. Eye Res. 49:591–609PubMedGoogle Scholar
  29. Rae, J.L., Levis, R.A. 1984. Patch voltage clamp of lens epithelial cells: Theory and practice.Molec. Physiol. 6:115–162Google Scholar
  30. Rae, J.L., Levis, R.A., Eisenberg, R.S. 1988. Ionic channels in ocular epithelia.In: Ion Channels. T. Narahashi, editor. pp. 283–327. Plenum, New YorkGoogle Scholar
  31. Rae, J.L., Mathias, R.T. 1985. The physiology of the lens.In: The Ocular Lens: Structure, Function, and Pathology. H. Maisel, editor. pp. 93–121. Marcel Dekker, New York-BaselGoogle Scholar
  32. Reddan, J.R., McGee, S.J., Goldenberg, E.M., Dziedzic, D.C. 1982/1983. Both human and newborn rabbit lens epithelial cells exhibit similar limited growth properties in tissue culture.Curr. Eye Res. 2:399–405Google Scholar
  33. Reddy, V.N., Lin, L.R., Arita, T., Zigler, J.S., Huang, Q.L. 1988. Crystallins and their synthesis in human lens epithelial cells in tissue culture.Exp. Eye Res. 47:465–478PubMedGoogle Scholar
  34. Stewart, S., Duncan, G., Marcantonio, J.M., Prescott, A.R. 1988. Membrane and communication properties of tissue cultured human lens epithelial cells.Invest. Ophthalmol. Vis. Sci. 29:1713–1725PubMedGoogle Scholar
  35. Welsh, M.L. 1987. Electrolyte transport by airway epithelia.Physiol. Rev. 67:1143–1184PubMedGoogle Scholar
  36. Wills, N.K., Zweifach, A. 1987. Recent advances in the characterization of epithelial ionic channels.Biochim. Biophys. Acta 906:1–31PubMedGoogle Scholar

Copyright information

© Springer-Verlag New York Inc. 1990

Authors and Affiliations

  • Kim Cooper
    • 1
  • Peter Gates
    • 1
  • James L. Rae
    • 1
  • Jerry Dewey
    • 1
  1. 1.Departments of Physiology and Biophysics and OphthalmologyMayo FoundationRochester

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